Move channel header to collapsible app bar

app/src/main/java/org/schabi/newpipe/fragments/list/channel/ChannelFragment.java

@@ -1,10 +1,16 @@
 package org.schabi.newpipe.fragments.list.channel;
 
+import static org.schabi.newpipe.ktx.TextViewUtils.animateTextColor;
+import static org.schabi.newpipe.ktx.ViewUtils.animate;
+import static org.schabi.newpipe.ktx.ViewUtils.animateBackgroundColor;
+
 import android.content.Context;
 import android.content.SharedPreferences;
+import android.graphics.Color;
 import android.os.Bundle;
 import android.text.TextUtils;
 import android.util.Log;
+import android.util.TypedValue;
 import android.view.LayoutInflater;
 import android.view.Menu;
 import android.view.MenuInflater;
@@ -14,43 +20,59 @@ import android.view.ViewGroup;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+import androidx.core.content.ContextCompat;
+import androidx.core.graphics.ColorUtils;
 import androidx.preference.PreferenceManager;
 
+import com.google.android.material.snackbar.Snackbar;
 import com.google.android.material.tabs.TabLayout;
+import com.jakewharton.rxbinding4.view.RxView;
 
 import org.schabi.newpipe.R;
 import org.schabi.newpipe.database.subscription.NotificationMode;
 import org.schabi.newpipe.database.subscription.SubscriptionEntity;
 import org.schabi.newpipe.databinding.FragmentChannelBinding;
 import org.schabi.newpipe.error.ErrorInfo;
+import org.schabi.newpipe.error.ErrorUtil;
 import org.schabi.newpipe.error.UserAction;
 import org.schabi.newpipe.extractor.channel.ChannelInfo;
 import org.schabi.newpipe.extractor.exceptions.ContentNotSupportedException;
 import org.schabi.newpipe.extractor.linkhandler.ListLinkHandler;
 import org.schabi.newpipe.fragments.BaseStateFragment;
 import org.schabi.newpipe.fragments.detail.TabAdapter;
+import org.schabi.newpipe.ktx.AnimationType;
 import org.schabi.newpipe.local.feed.notifications.NotificationHelper;
 import org.schabi.newpipe.local.subscription.SubscriptionManager;
 import org.schabi.newpipe.util.ChannelTabHelper;
 import org.schabi.newpipe.util.Constants;
 import org.schabi.newpipe.util.ExtractorHelper;
+import org.schabi.newpipe.util.Localization;
 import org.schabi.newpipe.util.NavigationHelper;
+import org.schabi.newpipe.util.PicassoHelper;
 import org.schabi.newpipe.util.StateSaver;
+import org.schabi.newpipe.util.ThemeHelper;
 import org.schabi.newpipe.util.external_communication.ShareUtils;
 
 import java.util.List;
 import java.util.Queue;
+import java.util.concurrent.TimeUnit;
 
 import icepick.State;
 import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers;
 import io.reactivex.rxjava3.core.Observable;
 import io.reactivex.rxjava3.disposables.CompositeDisposable;
 import io.reactivex.rxjava3.disposables.Disposable;
+import io.reactivex.rxjava3.functions.Action;
 import io.reactivex.rxjava3.functions.Consumer;
+import io.reactivex.rxjava3.functions.Function;
 import io.reactivex.rxjava3.schedulers.Schedulers;
 
 public class ChannelFragment extends BaseStateFragment<ChannelInfo>
         implements StateSaver.WriteRead {
+
+    private static final int BUTTON_DEBOUNCE_INTERVAL = 100;
+    private static final String PICASSO_CHANNEL_TAG = "PICASSO_CHANNEL_TAG";
+
     @State
     protected int serviceId = Constants.NO_SERVICE_ID;
     @State
@@ -60,13 +82,11 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
 
     private ChannelInfo currentInfo;
     private Disposable currentWorker;
-    private Disposable subscriptionMonitor;
     private final CompositeDisposable disposables = new CompositeDisposable();
+    private Disposable subscribeButtonMonitor;
     private SubscriptionManager subscriptionManager;
     private int lastTab;
-
+    private boolean channelContentNotSupported = false;
-    private MenuItem menuRssButton;
-    private MenuItem menuNotifyButton;
 
     /*//////////////////////////////////////////////////////////////////////////
     // Views
@@ -75,6 +95,9 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
     private FragmentChannelBinding binding;
     private TabAdapter tabAdapter;
 
+    private MenuItem menuRssButton;
+    private MenuItem menuNotifyButton;
+
     public static ChannelFragment getInstance(final int serviceId, final String url,
                                               final String name) {
         final ChannelFragment instance = new ChannelFragment();
@@ -82,12 +105,13 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
         return instance;
     }
 
-    protected void setInitialData(final int sid, final String u, final String title) {
+    private void setInitialData(final int sid, final String u, final String title) {
         this.serviceId = sid;
         this.url = u;
         this.name = !TextUtils.isEmpty(title) ? title : "";
     }
 
+
     /*//////////////////////////////////////////////////////////////////////////
     // LifeCycle
     //////////////////////////////////////////////////////////////////////////*/
@@ -96,12 +120,6 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
     public void onCreate(final Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setHasOptionsMenu(true);
-
-        if (savedInstanceState != null) {
-            lastTab = savedInstanceState.getInt("LastTab");
-        } else {
-            lastTab = 0;
-        }
     }
 
     @Override
@@ -125,14 +143,29 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
         tabAdapter = new TabAdapter(getChildFragmentManager());
         binding.viewPager.setAdapter(tabAdapter);
         binding.tabLayout.setupWithViewPager(binding.viewPager);
+
+        binding.channelTitleView.setText(name);
     }
 
     @Override
-    public void onSaveInstanceState(final @NonNull Bundle outState) {
+    protected void initListeners() {
-        super.onSaveInstanceState(outState);
+        super.initListeners();
-        if (binding != null) {
+
-            outState.putInt("LastTab", binding.tabLayout.getSelectedTabPosition());
+        final View.OnClickListener openSubChannel = v -> {
-        }
+            if (!TextUtils.isEmpty(currentInfo.getParentChannelUrl())) {
+                try {
+                    NavigationHelper.openChannelFragment(getFM(), currentInfo.getServiceId(),
+                            currentInfo.getParentChannelUrl(),
+                            currentInfo.getParentChannelName());
+                } catch (final Exception e) {
+                    ErrorUtil.showUiErrorSnackbar(this, "Opening channel fragment", e);
+                }
+            } else if (DEBUG) {
+                Log.i(TAG, "Can't open parent channel because we got no channel URL");
+            }
+        };
+        binding.subChannelAvatarView.setOnClickListener(openSubChannel);
+        binding.subChannelTitleView.setOnClickListener(openSubChannel);
     }
 
     @Override
@@ -141,14 +174,12 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
         if (currentWorker != null) {
             currentWorker.dispose();
         }
-        if (subscriptionMonitor != null) {
-            subscriptionMonitor.dispose();
-        }
         disposables.clear();
         binding = null;
     }
 
-     /*//////////////////////////////////////////////////////////////////////////
+
+    /*//////////////////////////////////////////////////////////////////////////
     // Menu
     //////////////////////////////////////////////////////////////////////////*/
 
@@ -164,8 +195,6 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
         }
         menuRssButton = menu.findItem(R.id.menu_item_rss);
         menuNotifyButton = menu.findItem(R.id.menu_item_notify);
-        updateRssButton();
-        monitorSubscription();
     }
 
     @Override
@@ -201,37 +230,168 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
         return true;
     }
 
-    private void updateRssButton() {
+
-        if (currentInfo != null && menuRssButton != null) {
+    /*//////////////////////////////////////////////////////////////////////////
-            menuRssButton.setVisible(!TextUtils.isEmpty(currentInfo.getFeedUrl()));
+    // Channel Subscription
-        }
+    //////////////////////////////////////////////////////////////////////////*/
+
+    private void monitorSubscription(final ChannelInfo info) {
+        final Consumer<Throwable> onError = (Throwable throwable) -> {
+            animate(binding.channelSubscribeButton, false, 100);
+            showSnackBarError(new ErrorInfo(throwable, UserAction.SUBSCRIPTION_GET,
+                    "Get subscription status", currentInfo));
+        };
+
+        final Observable<List<SubscriptionEntity>> observable = subscriptionManager
+                .subscriptionTable()
+                .getSubscriptionFlowable(info.getServiceId(), info.getUrl())
+                .toObservable();
+
+        disposables.add(observable
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(getSubscribeUpdateMonitor(info), onError));
+
+        disposables.add(observable
+                .map(List::isEmpty)
+                .distinctUntilChanged()
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(isEmpty -> updateSubscribeButton(!isEmpty), onError));
+
+        disposables.add(observable
+                .map(List::isEmpty)
+                .distinctUntilChanged()
+                .skip(1) // channel has just been opened
+                .filter(x -> NotificationHelper.areNewStreamsNotificationsEnabled(requireContext()))
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(isEmpty -> {
+                    if (!isEmpty) {
+                        showNotifySnackbar();
+                    }
+                }, onError));
     }
 
-    private void monitorSubscription() {
+    private Function<Object, Object> mapOnSubscribe(final SubscriptionEntity subscription,
-        if (currentInfo != null) {
+                                                    final ChannelInfo info) {
-            final Observable<List<SubscriptionEntity>> observable = subscriptionManager
+        return (@NonNull Object o) -> {
-                    .subscriptionTable()
+            subscriptionManager.insertSubscription(subscription, info);
-                    .getSubscriptionFlowable(currentInfo.getServiceId(), currentInfo.getUrl())
+            return o;
-                    .toObservable();
+        };
-
-            if (subscriptionMonitor != null) {
-                subscriptionMonitor.dispose();
-            }
-            subscriptionMonitor = observable
-                    .observeOn(AndroidSchedulers.mainThread())
-                    .subscribe(getSubscribeUpdateMonitor());
-        }
     }
 
-    private Consumer<List<SubscriptionEntity>> getSubscribeUpdateMonitor() {
+    private Function<Object, Object> mapOnUnsubscribe(final SubscriptionEntity subscription) {
-        return (List<SubscriptionEntity> subscriptionEntities) -> {
+        return (@NonNull Object o) -> {
-            if (subscriptionEntities.isEmpty()) {
+            subscriptionManager.deleteSubscription(subscription);
-                updateNotifyButton(null);
+            return o;
-            } else {
+        };
-                final SubscriptionEntity subscription = subscriptionEntities.get(0);
+    }
-                updateNotifyButton(subscription);
+
+    private void updateSubscription(final ChannelInfo info) {
+        if (DEBUG) {
+            Log.d(TAG, "updateSubscription() called with: info = [" + info + "]");
+        }
+        final Action onComplete = () -> {
+            if (DEBUG) {
+                Log.d(TAG, "Updated subscription: " + info.getUrl());
             }
         };
+
+        final Consumer<Throwable> onError = (@NonNull Throwable throwable) ->
+                showSnackBarError(new ErrorInfo(throwable, UserAction.SUBSCRIPTION_UPDATE,
+                        "Updating subscription for " + info.getUrl(), info));
+
+        disposables.add(subscriptionManager.updateChannelInfo(info)
+                .subscribeOn(Schedulers.io())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(onComplete, onError));
+    }
+
+    private Disposable monitorSubscribeButton(final Function<Object, Object> action) {
+        final Consumer<Object> onNext = (@NonNull Object o) -> {
+            if (DEBUG) {
+                Log.d(TAG, "Changed subscription status to this channel!");
+            }
+        };
+
+        final Consumer<Throwable> onError = (@NonNull Throwable throwable) ->
+                showSnackBarError(new ErrorInfo(throwable, UserAction.SUBSCRIPTION_CHANGE,
+                        "Changing subscription for " + currentInfo.getUrl(), currentInfo));
+
+        /* Emit clicks from main thread unto io thread */
+        return RxView.clicks(binding.channelSubscribeButton)
+                .subscribeOn(AndroidSchedulers.mainThread())
+                .observeOn(Schedulers.io())
+                .debounce(BUTTON_DEBOUNCE_INTERVAL, TimeUnit.MILLISECONDS) // Ignore rapid clicks
+                .map(action)
+                .subscribe(onNext, onError);
+    }
+
+    private Consumer<List<SubscriptionEntity>> getSubscribeUpdateMonitor(final ChannelInfo info) {
+        return (List<SubscriptionEntity> subscriptionEntities) -> {
+            if (DEBUG) {
+                Log.d(TAG, "subscriptionManager.subscriptionTable.doOnNext() called with: "
+                        + "subscriptionEntities = [" + subscriptionEntities + "]");
+            }
+            if (subscribeButtonMonitor != null) {
+                subscribeButtonMonitor.dispose();
+            }
+
+            if (subscriptionEntities.isEmpty()) {
+                if (DEBUG) {
+                    Log.d(TAG, "No subscription to this channel!");
+                }
+                final SubscriptionEntity channel = new SubscriptionEntity();
+                channel.setServiceId(info.getServiceId());
+                channel.setUrl(info.getUrl());
+                channel.setData(info.getName(),
+                        info.getAvatarUrl(),
+                        info.getDescription(),
+                        info.getSubscriberCount());
+                updateNotifyButton(null);
+                subscribeButtonMonitor = monitorSubscribeButton(mapOnSubscribe(channel, info));
+            } else {
+                if (DEBUG) {
+                    Log.d(TAG, "Found subscription to this channel!");
+                }
+                final SubscriptionEntity subscription = subscriptionEntities.get(0);
+                updateNotifyButton(subscription);
+                subscribeButtonMonitor = monitorSubscribeButton(mapOnUnsubscribe(subscription));
+            }
+        };
+    }
+
+    private void updateSubscribeButton(final boolean isSubscribed) {
+        if (DEBUG) {
+            Log.d(TAG, "updateSubscribeButton() called with: "
+                    + "isSubscribed = [" + isSubscribed + "]");
+        }
+
+        final boolean isButtonVisible = binding.channelSubscribeButton.getVisibility()
+                == View.VISIBLE;
+        final int backgroundDuration = isButtonVisible ? 300 : 0;
+        final int textDuration = isButtonVisible ? 200 : 0;
+
+        final int subscribedBackground = ContextCompat
+                .getColor(activity, R.color.subscribed_background_color);
+        final int subscribedText = ContextCompat.getColor(activity, R.color.subscribed_text_color);
+        final int subscribeBackground = ColorUtils.blendARGB(ThemeHelper
+                .resolveColorFromAttr(activity, R.attr.colorPrimary), subscribedBackground, 0.35f);
+        final int subscribeText = ContextCompat.getColor(activity, R.color.subscribe_text_color);
+
+        if (isSubscribed) {
+            binding.channelSubscribeButton.setText(R.string.subscribed_button_title);
+            animateBackgroundColor(binding.channelSubscribeButton, backgroundDuration,
+                    subscribeBackground, subscribedBackground);
+            animateTextColor(binding.channelSubscribeButton, textDuration, subscribeText,
+                    subscribedText);
+        } else {
+            binding.channelSubscribeButton.setText(R.string.subscribe_button_title);
+            animateBackgroundColor(binding.channelSubscribeButton, backgroundDuration,
+                    subscribedBackground, subscribeBackground);
+            animateTextColor(binding.channelSubscribeButton, textDuration, subscribedText,
+                    subscribeText);
+        }
+
+        animate(binding.channelSubscribeButton, true, 100, AnimationType.LIGHT_SCALE_AND_ALPHA);
     }
 
     private void updateNotifyButton(@Nullable final SubscriptionEntity subscription) {
@@ -263,52 +423,48 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
         );
     }
 
+    /**
+     * Show a snackbar with the option to enable notifications on new streams for this channel.
+     */
+    private void showNotifySnackbar() {
+        Snackbar.make(binding.getRoot(), R.string.you_successfully_subscribed, Snackbar.LENGTH_LONG)
+                .setAction(R.string.get_notified, v -> setNotify(true))
+                .setActionTextColor(Color.YELLOW)
+                .show();
+    }
+
+
     /*//////////////////////////////////////////////////////////////////////////
     // Init
     //////////////////////////////////////////////////////////////////////////*/
 
-    private boolean isContentUnsupported() {
-        for (final Throwable throwable : currentInfo.getErrors()) {
-            if (throwable instanceof ContentNotSupportedException) {
-                return true;
-            }
-        }
-        return false;
-    }
-
     private void updateTabs() {
         tabAdapter.clearAllItems();
 
-        if (currentInfo != null) {
+        if (currentInfo != null && !channelContentNotSupported) {
-            if (isContentUnsupported()) {
+            tabAdapter.addFragment(new ChannelVideosFragment(currentInfo), "Videos");
-                showEmptyState();
-                binding.errorContentNotSupported.setVisibility(View.VISIBLE);
-            } else {
-                tabAdapter.addFragment(
-                        ChannelVideosFragment.getInstance(currentInfo), "Videos");
 
-                final Context context = getContext();
+            final Context context = requireContext();
-                final SharedPreferences preferences = PreferenceManager
+            final SharedPreferences preferences = PreferenceManager
-                        .getDefaultSharedPreferences(context);
+                    .getDefaultSharedPreferences(context);
 
-                for (final ListLinkHandler linkHandler : currentInfo.getTabs()) {
+            for (final ListLinkHandler linkHandler : currentInfo.getTabs()) {
-                    final String tab = linkHandler.getContentFilters().get(0);
+                final String tab = linkHandler.getContentFilters().get(0);
-                    if (ChannelTabHelper.showChannelTab(context, preferences, tab)) {
+                if (ChannelTabHelper.showChannelTab(context, preferences, tab)) {
-                        tabAdapter.addFragment(
-                                ChannelTabFragment.getInstance(serviceId, linkHandler, name),
-                                context.getString(ChannelTabHelper.getTranslationKey(tab)));
-                    }
-                }
-
-                final String description = currentInfo.getDescription();
-                if (description != null && !description.isEmpty()
-                        && ChannelTabHelper.showChannelTab(
-                        context, preferences, R.string.show_channel_tabs_about)) {
                     tabAdapter.addFragment(
-                            ChannelAboutFragment.getInstance(currentInfo),
+                            ChannelTabFragment.getInstance(serviceId, linkHandler, name),
-                            context.getString(R.string.channel_tab_about));
+                            context.getString(ChannelTabHelper.getTranslationKey(tab)));
                 }
             }
+
+            final String description = currentInfo.getDescription();
+            if (description != null && !description.isEmpty()
+                    && ChannelTabHelper.showChannelTab(
+                    context, preferences, R.string.show_channel_tabs_about)) {
+                tabAdapter.addFragment(
+                        ChannelAboutFragment.getInstance(currentInfo),
+                        context.getString(R.string.channel_tab_about));
+            }
         }
 
         tabAdapter.notifyDataSetUpdate();
@@ -324,6 +480,7 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
         }
     }
 
+
     /*//////////////////////////////////////////////////////////////////////////
     // State Saving
     //////////////////////////////////////////////////////////////////////////*/
@@ -336,11 +493,7 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
     @Override
     public void writeTo(final Queue<Object> objectsToSave) {
         objectsToSave.add(currentInfo);
-        if (binding != null) {
+        objectsToSave.add(binding == null ? 0 : binding.tabLayout.getSelectedTabPosition());
-            objectsToSave.add(binding.tabLayout.getSelectedTabPosition());
-        } else {
-            objectsToSave.add(0);
-        }
     }
 
     @Override
@@ -349,6 +502,25 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
         lastTab = (Integer) savedObjects.poll();
     }
 
+    @Override
+    public void onSaveInstanceState(final @NonNull Bundle outState) {
+        super.onSaveInstanceState(outState);
+        if (binding != null) {
+            outState.putInt("LastTab", binding.tabLayout.getSelectedTabPosition());
+        }
+    }
+
+    @Override
+    protected void onRestoreInstanceState(@NonNull final Bundle savedInstanceState) {
+        super.onRestoreInstanceState(savedInstanceState);
+        lastTab = savedInstanceState.getInt("LastTab", 0);
+    }
+
+
+    /*//////////////////////////////////////////////////////////////////////////
+    // Contract
+    //////////////////////////////////////////////////////////////////////////*/
+
     @Override
     protected void doInitialLoadLogic() {
         if (currentInfo == null) {
@@ -382,14 +554,77 @@ public class ChannelFragment extends BaseStateFragment<ChannelInfo>
                         url == null ? "no url" : url, serviceId)));
     }
 
+    @Override
+    public void showLoading() {
+        super.showLoading();
+        PicassoHelper.cancelTag(PICASSO_CHANNEL_TAG);
+        animate(binding.channelSubscribeButton, false, 100);
+    }
+
     @Override
     public void handleResult(@NonNull final ChannelInfo result) {
         super.handleResult(result);
         currentInfo = result;
         setInitialData(result.getServiceId(), result.getOriginalUrl(), result.getName());
 
+        binding.getRoot().setVisibility(View.VISIBLE);
+        PicassoHelper.loadBanner(result.getBannerUrl()).tag(PICASSO_CHANNEL_TAG)
+                .into(binding.channelBannerImage);
+        PicassoHelper.loadAvatar(result.getAvatarUrl()).tag(PICASSO_CHANNEL_TAG)
+                .into(binding.channelAvatarView);
+        PicassoHelper.loadAvatar(result.getParentChannelAvatarUrl()).tag(PICASSO_CHANNEL_TAG)
+                .into(binding.subChannelAvatarView);
+
+        binding.channelTitleView.setText(result.getName());
+        binding.channelSubscriberView.setVisibility(View.VISIBLE);
+        if (result.getSubscriberCount() >= 0) {
+            binding.channelSubscriberView.setText(Localization
+                    .shortSubscriberCount(activity, result.getSubscriberCount()));
+        } else {
+            binding.channelSubscriberView.setText(R.string.subscribers_count_not_available);
+        }
+
+        if (!TextUtils.isEmpty(currentInfo.getParentChannelName())) {
+            binding.subChannelTitleView.setText(String.format(
+                    getString(R.string.channel_created_by),
+                    currentInfo.getParentChannelName())
+            );
+            binding.subChannelTitleView.setVisibility(View.VISIBLE);
+            binding.subChannelAvatarView.setVisibility(View.VISIBLE);
+        }
+
+        if (menuRssButton != null) {
+            menuRssButton.setVisible(!TextUtils.isEmpty(result.getFeedUrl()));
+        }
+
+        channelContentNotSupported = false;
+        for (final Throwable throwable : result.getErrors()) {
+            if (throwable instanceof ContentNotSupportedException) {
+                channelContentNotSupported = true;
+                showContentNotSupportedIfNeeded();
+                break;
+            }
+        }
+
+        disposables.clear();
+        if (subscribeButtonMonitor != null) {
+            subscribeButtonMonitor.dispose();
+        }
+
         updateTabs();
-        updateRssButton();
+        updateSubscription(result);
-        monitorSubscription();
+        monitorSubscription(result);
+    }
+
+    private void showContentNotSupportedIfNeeded() {
+        // channelBinding might not be initialized when handleResult() is called
+        // (e.g. after rotating the screen, #6696)
+        if (!channelContentNotSupported || binding == null) {
+            return;
+        }
+
+        binding.errorContentNotSupported.setVisibility(View.VISIBLE);
+        binding.channelKaomoji.setText("(︶︹︺)");
+        binding.channelKaomoji.setTextSize(TypedValue.COMPLEX_UNIT_SP, 45f);
     }
 }

app/src/main/java/org/schabi/newpipe/fragments/list/channel/ChannelVideosFragment.java

@@ -1,109 +1,61 @@
 package org.schabi.newpipe.fragments.list.channel;
 
-import static org.schabi.newpipe.ktx.TextViewUtils.animateTextColor;
-import static org.schabi.newpipe.ktx.ViewUtils.animate;
-import static org.schabi.newpipe.ktx.ViewUtils.animateBackgroundColor;
-
-import android.content.Context;
-import android.graphics.Color;
 import android.os.Bundle;
-import android.text.TextUtils;
-import android.util.Log;
-import android.util.TypedValue;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
-import android.widget.Button;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
-import androidx.core.content.ContextCompat;
 
-import com.google.android.material.snackbar.Snackbar;
-import com.jakewharton.rxbinding4.view.RxView;
-
-import org.schabi.newpipe.R;
-import org.schabi.newpipe.database.subscription.NotificationMode;
-import org.schabi.newpipe.database.subscription.SubscriptionEntity;
-import org.schabi.newpipe.databinding.ChannelHeaderBinding;
 import org.schabi.newpipe.databinding.FragmentChannelVideosBinding;
 import org.schabi.newpipe.databinding.PlaylistControlBinding;
-import org.schabi.newpipe.error.ErrorInfo;
-import org.schabi.newpipe.error.ErrorUtil;
 import org.schabi.newpipe.error.UserAction;
 import org.schabi.newpipe.extractor.ListExtractor;
 import org.schabi.newpipe.extractor.channel.ChannelInfo;
-import org.schabi.newpipe.extractor.exceptions.ContentNotSupportedException;
 import org.schabi.newpipe.extractor.stream.StreamInfoItem;
 import org.schabi.newpipe.fragments.list.BaseListInfoFragment;
-import org.schabi.newpipe.ktx.AnimationType;
-import org.schabi.newpipe.local.feed.notifications.NotificationHelper;
-import org.schabi.newpipe.local.subscription.SubscriptionManager;
 import org.schabi.newpipe.player.PlayerType;
 import org.schabi.newpipe.player.playqueue.ChannelPlayQueue;
 import org.schabi.newpipe.player.playqueue.PlayQueue;
 import org.schabi.newpipe.util.ExtractorHelper;
-import org.schabi.newpipe.util.Localization;
 import org.schabi.newpipe.util.NavigationHelper;
-import org.schabi.newpipe.util.PicassoHelper;
-import org.schabi.newpipe.util.ThemeHelper;
 
 import java.util.List;
-import java.util.concurrent.TimeUnit;
 import java.util.function.Supplier;
 import java.util.stream.Collectors;
 
-import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers;
-import io.reactivex.rxjava3.core.Observable;
 import io.reactivex.rxjava3.core.Single;
 import io.reactivex.rxjava3.disposables.CompositeDisposable;
-import io.reactivex.rxjava3.disposables.Disposable;
-import io.reactivex.rxjava3.functions.Action;
-import io.reactivex.rxjava3.functions.Consumer;
-import io.reactivex.rxjava3.functions.Function;
-import io.reactivex.rxjava3.schedulers.Schedulers;
 
-public class ChannelVideosFragment extends BaseListInfoFragment<StreamInfoItem, ChannelInfo>
+public class ChannelVideosFragment extends BaseListInfoFragment<StreamInfoItem, ChannelInfo> {
-        implements View.OnClickListener {
-
-    private static final int BUTTON_DEBOUNCE_INTERVAL = 100;
-    private static final String PICASSO_CHANNEL_TAG = "PICASSO_CHANNEL_TAG";
 
     private final CompositeDisposable disposables = new CompositeDisposable();
-    private Disposable subscribeButtonMonitor;
-
-    private boolean channelContentNotSupported = false;
-
-    /*//////////////////////////////////////////////////////////////////////////
-    // Views
-    //////////////////////////////////////////////////////////////////////////*/
-
-    private SubscriptionManager subscriptionManager;
 
     private FragmentChannelVideosBinding channelBinding;
-    private ChannelHeaderBinding headerBinding;
     private PlaylistControlBinding playlistControlBinding;
 
-    public static ChannelVideosFragment getInstance(@NonNull final ChannelInfo channelInfo) {
-        final ChannelVideosFragment instance = new ChannelVideosFragment();
-        instance.setInitialData(channelInfo.getServiceId(), channelInfo.getUrl(),
-                channelInfo.getName());
-        instance.currentInfo = channelInfo;
-        instance.currentNextPage = channelInfo.getNextPage();
-        return instance;
-    }
 
-    public static ChannelVideosFragment getInstance(
+    /*//////////////////////////////////////////////////////////////////////////
-            final int serviceId, final String url, final String name) {
+    // Constructors and lifecycle
-        final ChannelVideosFragment instance = new ChannelVideosFragment();
+    //////////////////////////////////////////////////////////////////////////*/
-        instance.setInitialData(serviceId, url, name);
-        return instance;
-    }
 
+    // required by the Android framework to restore fragments after saving
     public ChannelVideosFragment() {
         super(UserAction.REQUESTED_CHANNEL);
     }
 
+    public ChannelVideosFragment(final int serviceId, final String url, final String name) {
+        this();
+        setInitialData(serviceId, url, name);
+    }
+
+    public ChannelVideosFragment(@NonNull final ChannelInfo info) {
+        this(info.getServiceId(), info.getUrl(), info.getName());
+        this.currentInfo = info;
+        this.currentNextPage = info.getNextPage();
+    }
+
     @Override
     public void onResume() {
         super.onResume();
@@ -112,22 +64,12 @@ public class ChannelVideosFragment extends BaseListInfoFragment<StreamInfoItem,
         }
     }
 
-    /*//////////////////////////////////////////////////////////////////////////
-    // LifeCycle
-    //////////////////////////////////////////////////////////////////////////*/
-
     @Override
     public void onCreate(final Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setHasOptionsMenu(false);
     }
 
-    @Override
-    public void onAttach(@NonNull final Context context) {
-        super.onAttach(context);
-        subscriptionManager = new SubscriptionManager(activity);
-    }
-
     @Override
     public View onCreateView(@NonNull final LayoutInflater inflater,
                              @Nullable final ViewGroup container,
@@ -136,235 +78,24 @@ public class ChannelVideosFragment extends BaseListInfoFragment<StreamInfoItem,
         return channelBinding.getRoot();
     }
 
-    @Override
-    public void onViewCreated(@NonNull final View rootView, final Bundle savedInstanceState) {
-        super.onViewCreated(rootView, savedInstanceState);
-        showContentNotSupportedIfNeeded();
-    }
-
     @Override
     public void onDestroy() {
         super.onDestroy();
         disposables.clear();
-        if (subscribeButtonMonitor != null) {
-            subscribeButtonMonitor.dispose();
-        }
         channelBinding = null;
-        headerBinding = null;
         playlistControlBinding = null;
     }
 
-    /*//////////////////////////////////////////////////////////////////////////
-    // Init
-    //////////////////////////////////////////////////////////////////////////*/
-
     @Override
     protected Supplier<View> getListHeaderSupplier() {
-        headerBinding = ChannelHeaderBinding
+        playlistControlBinding = PlaylistControlBinding
                 .inflate(activity.getLayoutInflater(), itemsList, false);
-        playlistControlBinding = headerBinding.playlistControl;
+        return playlistControlBinding::getRoot;
-
-        return headerBinding::getRoot;
     }
 
-    @Override
-    protected void initListeners() {
-        super.initListeners();
-
-        headerBinding.subChannelTitleView.setOnClickListener(this);
-        headerBinding.subChannelAvatarView.setOnClickListener(this);
-    }
 
     /*//////////////////////////////////////////////////////////////////////////
-    // Channel Subscription
+    // Loading
-    //////////////////////////////////////////////////////////////////////////*/
-
-    private void monitorSubscription(final ChannelInfo info) {
-        final Consumer<Throwable> onError = (Throwable throwable) -> {
-            animate(headerBinding.channelSubscribeButton, false, 100);
-            showSnackBarError(new ErrorInfo(throwable, UserAction.SUBSCRIPTION_GET,
-                    "Get subscription status", currentInfo));
-        };
-
-        final Observable<List<SubscriptionEntity>> observable = subscriptionManager
-                .subscriptionTable()
-                .getSubscriptionFlowable(info.getServiceId(), info.getUrl())
-                .toObservable();
-
-        disposables.add(observable
-                .observeOn(AndroidSchedulers.mainThread())
-                .subscribe(getSubscribeUpdateMonitor(info), onError));
-
-        disposables.add(observable
-                .map(List::isEmpty)
-                .distinctUntilChanged()
-                .observeOn(AndroidSchedulers.mainThread())
-                .subscribe(isEmpty -> updateSubscribeButton(!isEmpty), onError));
-
-        disposables.add(observable
-                .map(List::isEmpty)
-                .distinctUntilChanged()
-                .skip(1) // channel has just been opened
-                .filter(x -> NotificationHelper.areNewStreamsNotificationsEnabled(requireContext()))
-                .observeOn(AndroidSchedulers.mainThread())
-                .subscribe(isEmpty -> {
-                    if (!isEmpty) {
-                        showNotifySnackbar();
-                    }
-                }, onError));
-    }
-
-    private Function<Object, Object> mapOnSubscribe(final SubscriptionEntity subscription,
-                                                    final ChannelInfo info) {
-        return (@NonNull Object o) -> {
-            subscriptionManager.insertSubscription(subscription, info);
-            return o;
-        };
-    }
-
-    private Function<Object, Object> mapOnUnsubscribe(final SubscriptionEntity subscription) {
-        return (@NonNull Object o) -> {
-            subscriptionManager.deleteSubscription(subscription);
-            return o;
-        };
-    }
-
-    private void updateSubscription(final ChannelInfo info) {
-        if (DEBUG) {
-            Log.d(TAG, "updateSubscription() called with: info = [" + info + "]");
-        }
-        final Action onComplete = () -> {
-            if (DEBUG) {
-                Log.d(TAG, "Updated subscription: " + info.getUrl());
-            }
-        };
-
-        final Consumer<Throwable> onError = (@NonNull Throwable throwable) ->
-                showSnackBarError(new ErrorInfo(throwable, UserAction.SUBSCRIPTION_UPDATE,
-                        "Updating subscription for " + info.getUrl(), info));
-
-        disposables.add(subscriptionManager.updateChannelInfo(info)
-                .subscribeOn(Schedulers.io())
-                .observeOn(AndroidSchedulers.mainThread())
-                .subscribe(onComplete, onError));
-    }
-
-    private Disposable monitorSubscribeButton(final Button subscribeButton,
-                                              final Function<Object, Object> action) {
-        final Consumer<Object> onNext = (@NonNull Object o) -> {
-            if (DEBUG) {
-                Log.d(TAG, "Changed subscription status to this channel!");
-            }
-        };
-
-        final Consumer<Throwable> onError = (@NonNull Throwable throwable) ->
-                showSnackBarError(new ErrorInfo(throwable, UserAction.SUBSCRIPTION_CHANGE,
-                        "Changing subscription for " + currentInfo.getUrl(), currentInfo));
-
-        /* Emit clicks from main thread unto io thread */
-        return RxView.clicks(subscribeButton)
-                .subscribeOn(AndroidSchedulers.mainThread())
-                .observeOn(Schedulers.io())
-                .debounce(BUTTON_DEBOUNCE_INTERVAL, TimeUnit.MILLISECONDS) // Ignore rapid clicks
-                .map(action)
-                .subscribe(onNext, onError);
-    }
-
-    private Consumer<List<SubscriptionEntity>> getSubscribeUpdateMonitor(final ChannelInfo info) {
-        return (List<SubscriptionEntity> subscriptionEntities) -> {
-            if (DEBUG) {
-                Log.d(TAG, "subscriptionManager.subscriptionTable.doOnNext() called with: "
-                        + "subscriptionEntities = [" + subscriptionEntities + "]");
-            }
-            if (subscribeButtonMonitor != null) {
-                subscribeButtonMonitor.dispose();
-            }
-
-            if (subscriptionEntities.isEmpty()) {
-                if (DEBUG) {
-                    Log.d(TAG, "No subscription to this channel!");
-                }
-                final SubscriptionEntity channel = new SubscriptionEntity();
-                channel.setServiceId(info.getServiceId());
-                channel.setUrl(info.getUrl());
-                channel.setData(info.getName(),
-                        info.getAvatarUrl(),
-                        info.getDescription(),
-                        info.getSubscriberCount());
-                subscribeButtonMonitor = monitorSubscribeButton(
-                        headerBinding.channelSubscribeButton, mapOnSubscribe(channel, info));
-            } else {
-                if (DEBUG) {
-                    Log.d(TAG, "Found subscription to this channel!");
-                }
-                final SubscriptionEntity subscription = subscriptionEntities.get(0);
-                subscribeButtonMonitor = monitorSubscribeButton(
-                        headerBinding.channelSubscribeButton, mapOnUnsubscribe(subscription));
-            }
-        };
-    }
-
-    private void updateSubscribeButton(final boolean isSubscribed) {
-        if (DEBUG) {
-            Log.d(TAG, "updateSubscribeButton() called with: "
-                    + "isSubscribed = [" + isSubscribed + "]");
-        }
-
-        final boolean isButtonVisible = headerBinding.channelSubscribeButton.getVisibility()
-                == View.VISIBLE;
-        final int backgroundDuration = isButtonVisible ? 300 : 0;
-        final int textDuration = isButtonVisible ? 200 : 0;
-
-        final int subscribeBackground = ThemeHelper
-                .resolveColorFromAttr(activity, R.attr.colorPrimary);
-        final int subscribeText = ContextCompat.getColor(activity, R.color.subscribe_text_color);
-        final int subscribedBackground = ContextCompat
-                .getColor(activity, R.color.subscribed_background_color);
-        final int subscribedText = ContextCompat.getColor(activity, R.color.subscribed_text_color);
-
-        if (!isSubscribed) {
-            headerBinding.channelSubscribeButton.setText(R.string.subscribe_button_title);
-            animateBackgroundColor(headerBinding.channelSubscribeButton, backgroundDuration,
-                    subscribedBackground, subscribeBackground);
-            animateTextColor(headerBinding.channelSubscribeButton, textDuration, subscribedText,
-                    subscribeText);
-        } else {
-            headerBinding.channelSubscribeButton.setText(R.string.subscribed_button_title);
-            animateBackgroundColor(headerBinding.channelSubscribeButton, backgroundDuration,
-                    subscribeBackground, subscribedBackground);
-            animateTextColor(headerBinding.channelSubscribeButton, textDuration, subscribeText,
-                    subscribedText);
-        }
-
-        animate(headerBinding.channelSubscribeButton, true, 100,
-                AnimationType.LIGHT_SCALE_AND_ALPHA);
-    }
-
-    /**
-     * Show a snackbar with the option to enable notifications on new streams for this channel.
-     */
-    private void showNotifySnackbar() {
-        Snackbar.make(itemsList, R.string.you_successfully_subscribed, Snackbar.LENGTH_LONG)
-                .setAction(R.string.get_notified, v -> setNotify(true))
-                .setActionTextColor(Color.YELLOW)
-                .show();
-    }
-
-    private void setNotify(final boolean isEnabled) {
-        disposables.add(
-                subscriptionManager
-                        .updateNotificationMode(
-                                currentInfo.getServiceId(),
-                                currentInfo.getUrl(),
-                                isEnabled ? NotificationMode.ENABLED : NotificationMode.DISABLED)
-                        .subscribeOn(Schedulers.io())
-                        .observeOn(AndroidSchedulers.mainThread())
-                        .subscribe()
-        );
-    }
-
-    /*//////////////////////////////////////////////////////////////////////////
-    // Load and handle
     //////////////////////////////////////////////////////////////////////////*/
 
     @Override
@@ -377,76 +108,15 @@ public class ChannelVideosFragment extends BaseListInfoFragment<StreamInfoItem,
         return ExtractorHelper.getChannelInfo(serviceId, url, forceLoad);
     }
 
-    /*//////////////////////////////////////////////////////////////////////////
-    // OnClick
-    //////////////////////////////////////////////////////////////////////////*/
-
-    @Override
-    public void onClick(final View v) {
-        if (isLoading.get() || currentInfo == null) {
-            return;
-        }
-
-        switch (v.getId()) {
-            case R.id.sub_channel_avatar_view:
-            case R.id.sub_channel_title_view:
-                if (!TextUtils.isEmpty(currentInfo.getParentChannelUrl())) {
-                    try {
-                        NavigationHelper.openChannelFragment(getFM(), currentInfo.getServiceId(),
-                                currentInfo.getParentChannelUrl(),
-                                currentInfo.getParentChannelName());
-                    } catch (final Exception e) {
-                        ErrorUtil.showUiErrorSnackbar(this, "Opening channel fragment", e);
-                    }
-                } else if (DEBUG) {
-                    Log.i(TAG, "Can't open parent channel because we got no channel URL");
-                }
-                break;
-        }
-    }
 
     /*//////////////////////////////////////////////////////////////////////////
     // Contract
     //////////////////////////////////////////////////////////////////////////*/
 
-    @Override
-    public void showLoading() {
-        super.showLoading();
-        PicassoHelper.cancelTag(PICASSO_CHANNEL_TAG);
-        animate(headerBinding.channelSubscribeButton, false, 100);
-    }
-
     @Override
     public void handleResult(@NonNull final ChannelInfo result) {
         super.handleResult(result);
 
-        headerBinding.getRoot().setVisibility(View.VISIBLE);
-        PicassoHelper.loadBanner(result.getBannerUrl()).tag(PICASSO_CHANNEL_TAG)
-                .into(headerBinding.channelBannerImage);
-        PicassoHelper.loadAvatar(result.getAvatarUrl()).tag(PICASSO_CHANNEL_TAG)
-                .into(headerBinding.channelAvatarView);
-        PicassoHelper.loadAvatar(result.getParentChannelAvatarUrl()).tag(PICASSO_CHANNEL_TAG)
-                .into(headerBinding.subChannelAvatarView);
-
-        headerBinding.channelSubscriberView.setVisibility(View.VISIBLE);
-        if (result.getSubscriberCount() >= 0) {
-            headerBinding.channelSubscriberView.setText(Localization
-                    .shortSubscriberCount(activity, result.getSubscriberCount()));
-        } else {
-            headerBinding.channelSubscriberView.setText(R.string.subscribers_count_not_available);
-        }
-
-        if (!TextUtils.isEmpty(currentInfo.getParentChannelName())) {
-            headerBinding.subChannelTitleView.setText(String.format(
-                    getString(R.string.channel_created_by),
-                    currentInfo.getParentChannelName())
-            );
-            headerBinding.subChannelTitleView.setVisibility(View.VISIBLE);
-            headerBinding.subChannelAvatarView.setVisibility(View.VISIBLE);
-        } else {
-            headerBinding.subChannelTitleView.setVisibility(View.GONE);
-        }
-
         // PlaylistControls should be visible only if there is some item in
         // infoListAdapter other than header
         if (infoListAdapter.getItemCount() != 1) {
@@ -455,31 +125,14 @@ public class ChannelVideosFragment extends BaseListInfoFragment<StreamInfoItem,
             playlistControlBinding.getRoot().setVisibility(View.GONE);
         }
 
-        channelContentNotSupported = false;
-        for (final Throwable throwable : result.getErrors()) {
-            if (throwable instanceof ContentNotSupportedException) {
-                channelContentNotSupported = true;
-                showContentNotSupportedIfNeeded();
-                break;
-            }
-        }
-
         disposables.clear();
-        if (subscribeButtonMonitor != null) {
-            subscribeButtonMonitor.dispose();
-        }
-        updateSubscription(result);
-        monitorSubscription(result);
 
-        playlistControlBinding.playlistCtrlPlayAllButton
+        playlistControlBinding.playlistCtrlPlayAllButton.setOnClickListener(
-                .setOnClickListener(view -> NavigationHelper
+                view -> NavigationHelper.playOnMainPlayer(activity, getPlayQueue()));
-                        .playOnMainPlayer(activity, getPlayQueue()));
+        playlistControlBinding.playlistCtrlPlayPopupButton.setOnClickListener(
-        playlistControlBinding.playlistCtrlPlayPopupButton
+                view -> NavigationHelper.playOnPopupPlayer(activity, getPlayQueue(), false));
-                .setOnClickListener(view -> NavigationHelper
+        playlistControlBinding.playlistCtrlPlayBgButton.setOnClickListener(
-                        .playOnPopupPlayer(activity, getPlayQueue(), false));
+                view -> NavigationHelper.playOnBackgroundPlayer(activity, getPlayQueue(), false));
-        playlistControlBinding.playlistCtrlPlayBgButton
-                .setOnClickListener(view -> NavigationHelper
-                        .playOnBackgroundPlayer(activity, getPlayQueue(), false));
 
         playlistControlBinding.playlistCtrlPlayPopupButton.setOnLongClickListener(view -> {
             NavigationHelper.enqueueOnPlayer(activity, getPlayQueue(), PlayerType.POPUP);
@@ -492,19 +145,6 @@ public class ChannelVideosFragment extends BaseListInfoFragment<StreamInfoItem,
         });
     }
 
-    private void showContentNotSupportedIfNeeded() {
-        // channelBinding might not be initialized when handleResult() is called
-        // (e.g. after rotating the screen, #6696)
-        if (!channelContentNotSupported || channelBinding == null) {
-            return;
-        }
-
-        channelBinding.errorContentNotSupported.setVisibility(View.VISIBLE);
-        channelBinding.channelKaomoji.setText("(︶︹︺)");
-        channelBinding.channelKaomoji.setTextSize(TypedValue.COMPLEX_UNIT_SP, 45f);
-        channelBinding.channelNoVideos.setVisibility(View.GONE);
-    }
-
     private PlayQueue getPlayQueue() {
         final List<StreamInfoItem> streamItems = infoListAdapter.getItemsList().stream()
                 .filter(StreamInfoItem.class::isInstance)
@@ -514,14 +154,4 @@ public class ChannelVideosFragment extends BaseListInfoFragment<StreamInfoItem,
         return new ChannelPlayQueue(currentInfo.getServiceId(), currentInfo.getUrl(),
                 currentInfo.getNextPage(), streamItems, 0);
     }
-
-    /*//////////////////////////////////////////////////////////////////////////
-    // Utils
-    //////////////////////////////////////////////////////////////////////////*/
-
-    @Override
-    public void setTitle(final String title) {
-        super.setTitle(title);
-        headerBinding.channelTitleView.setText(title);
-    }
 }

app/src/main/java/org/schabi/newpipe/settings/tabs/Tab.java

@@ -433,7 +433,7 @@ public abstract class Tab {
 
         @Override
         public ChannelVideosFragment getFragment(final Context context) {
-            return ChannelVideosFragment.getInstance(channelServiceId, channelUrl, channelName);
+            return new ChannelVideosFragment(channelServiceId, channelUrl, channelName);
         }
 
         @Override

app/src/main/java/org/schabi/newpipe/util/PicassoHelper.java

@@ -109,7 +109,11 @@ public final class PicassoHelper {
     }
 
     public static RequestCreator loadBanner(final String url) {
-        return loadImageDefault(url, R.drawable.placeholder_channel_banner);
+        if (!shouldLoadImages || isBlank(url)) {
+            return picassoInstance.load((String) null);
+        } else {
+            return picassoInstance.load(url);
+        }
     }
 
     public static RequestCreator loadPlaylistThumbnail(final String url) {

app/src/main/res/layout/channel_header.xml

@@ -1,131 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:app="http://schemas.android.com/apk/res-auto"
-    xmlns:tools="http://schemas.android.com/tools"
-    android:layout_width="match_parent"
-    android:layout_height="wrap_content"
-    android:background="?attr/contrast_background_color">
-
-    <RelativeLayout
-        android:id="@+id/channel_metadata"
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content">
-
-        <ImageView
-            android:id="@+id/channel_banner_image"
-            android:layout_width="match_parent"
-            android:layout_height="70dp"
-            android:background="@android:color/black"
-            android:fitsSystemWindows="true"
-            android:scaleType="fitCenter"
-            android:src="@drawable/placeholder_channel_banner"
-            tools:ignore="ContentDescription" />
-
-        <FrameLayout
-            android:id="@+id/avatars_layout"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_marginLeft="8dp"
-            android:layout_marginTop="50dp">
-
-            <com.google.android.material.imageview.ShapeableImageView
-                android:id="@+id/channel_avatar_view"
-                android:layout_width="@dimen/channel_avatar_size"
-                android:layout_height="@dimen/channel_avatar_size"
-                android:padding="1dp"
-                android:src="@drawable/placeholder_person"
-                app:shapeAppearance="@style/CircularImageView"
-                app:strokeColor="#ffffff"
-                app:strokeWidth="2dp" />
-
-            <com.google.android.material.imageview.ShapeableImageView
-                android:id="@+id/sub_channel_avatar_view"
-                android:layout_width="@dimen/sub_channel_avatar_size"
-                android:layout_height="@dimen/sub_channel_avatar_size"
-                android:layout_gravity="bottom|right"
-                android:padding="1dp"
-                android:src="@drawable/placeholder_person"
-                android:visibility="gone"
-                app:shapeAppearance="@style/CircularImageView"
-                app:strokeColor="#ffffff"
-                app:strokeWidth="2dp"
-                tools:ignore="RtlHardcoded"
-                tools:visibility="visible" />
-        </FrameLayout>
-
-        <org.schabi.newpipe.views.NewPipeTextView
-            android:id="@+id/channel_title_view"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:layout_below="@id/channel_banner_image"
-            android:layout_marginLeft="8dp"
-            android:layout_marginTop="6dp"
-            android:layout_marginRight="8dp"
-            android:layout_toLeftOf="@id/channel_subscribe_button"
-            android:layout_toRightOf="@id/avatars_layout"
-            android:ellipsize="end"
-            android:lines="1"
-            android:textAppearance="?android:attr/textAppearanceLarge"
-            android:textSize="@dimen/video_item_detail_title_text_size"
-            tools:ignore="RtlHardcoded"
-            tools:text="Lorem ipsum dolor" />
-
-        <org.schabi.newpipe.views.NewPipeTextView
-            android:id="@+id/sub_channel_title_view"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:layout_below="@id/channel_title_view"
-            android:layout_alignLeft="@id/channel_title_view"
-            android:layout_alignRight="@id/channel_title_view"
-            android:ellipsize="end"
-            android:gravity="center|left"
-            android:lines="1"
-            android:textAppearance="?android:attr/textAppearanceLarge"
-            android:textSize="12dp"
-            tools:ignore="RtlHardcoded"
-            tools:layout_below="@id/channel_title_view"
-            tools:text="Lorem ipsum dolor" />
-
-        <org.schabi.newpipe.views.NewPipeTextView
-            android:id="@+id/channel_subscriber_view"
-            android:layout_width="match_parent"
-            android:layout_height="wrap_content"
-            android:layout_below="@id/sub_channel_title_view"
-            android:layout_alignLeft="@id/channel_title_view"
-            android:layout_alignRight="@id/channel_title_view"
-            android:ellipsize="end"
-            android:maxLines="2"
-            android:textSize="@dimen/channel_subscribers_text_size"
-            android:visibility="gone"
-            tools:ignore="RtlHardcoded"
-            tools:text="123,141,411 subscribers"
-            tools:visibility="visible" />
-
-        <androidx.appcompat.widget.AppCompatButton
-            android:id="@+id/channel_subscribe_button"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:layout_below="@+id/channel_banner_image"
-            android:layout_alignParentRight="true"
-            android:layout_gravity="center_vertical|right"
-            android:layout_marginRight="2dp"
-            android:text="@string/subscribe_button_title"
-            android:textSize="@dimen/channel_rss_title_size"
-            android:theme="@style/ServiceColoredButton"
-            android:visibility="gone"
-            tools:ignore="RtlHardcoded"
-            tools:visibility="visible" />
-    </RelativeLayout>
-
-    <LinearLayout
-        android:layout_width="match_parent"
-        android:layout_height="wrap_content"
-        android:layout_below="@id/channel_metadata">
-
-        <include
-            android:id="@+id/playlist_control"
-            layout="@layout/playlist_control" />
-
-    </LinearLayout>
-
-</RelativeLayout>

app/src/main/res/layout/fragment_channel.xml

@@ -1,75 +1,207 @@
 <?xml version="1.0" encoding="utf-8"?>
-<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent">
 
-    <com.google.android.material.tabs.TabLayout
+    <com.google.android.material.appbar.AppBarLayout
-        android:id="@+id/tab_layout"
+        android:id="@+id/app_bar_layout"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
-        android:background="?attr/colorPrimary"
+        app:elevation="0dp">
-        app:tabIndicatorColor="@color/white"
-        app:tabMode="scrollable"
-        app:tabRippleColor="@color/white"
-        app:tabTextColor="@color/white" />
 
-    <androidx.viewpager.widget.ViewPager
+        <org.schabi.newpipe.views.CustomCollapsingToolbarLayout
-        android:id="@+id/view_pager"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:fitsSystemWindows="true"
+            app:layout_scrollFlags="scroll|exitUntilCollapsed">
+
+            <androidx.constraintlayout.widget.ConstraintLayout
+                android:id="@+id/channel_metadata"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:fitsSystemWindows="true"
+                android:scaleType="centerCrop"
+                app:layout_collapseMode="parallax">
+
+                <ImageView
+                    android:id="@+id/channel_banner_image"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:adjustViewBounds="true"
+                    android:scaleType="centerCrop"
+                    tools:src="@drawable/placeholder_channel_banner"
+                    app:layout_constraintTop_toTopOf="parent"
+                    tools:ignore="ContentDescription" />
+
+                <com.google.android.material.imageview.ShapeableImageView
+                    android:id="@+id/channel_avatar_view"
+                    android:layout_width="@dimen/channel_avatar_size"
+                    android:layout_height="@dimen/channel_avatar_size"
+                    android:layout_marginVertical="8dp"
+                    android:layout_marginStart="8dp"
+                    android:padding="1dp"
+                    android:src="@drawable/placeholder_person"
+                    app:layout_constraintBottom_toBottomOf="parent"
+                    app:layout_constraintStart_toStartOf="parent"
+                    app:layout_constraintTop_toTopOf="parent"
+                    app:layout_constraintVertical_bias="1.0"
+                    app:shapeAppearance="@style/CircularImageView"
+                    app:strokeColor="#ffffff"
+                    app:strokeWidth="2dp" />
+
+                <com.google.android.material.imageview.ShapeableImageView
+                    android:id="@+id/sub_channel_avatar_view"
+                    android:layout_width="@dimen/sub_channel_avatar_size"
+                    android:layout_height="@dimen/sub_channel_avatar_size"
+                    android:padding="1dp"
+                    android:src="@drawable/placeholder_person"
+                    android:visibility="gone"
+                    app:layout_constraintBottom_toBottomOf="@id/channel_avatar_view"
+                    app:layout_constraintEnd_toEndOf="@id/channel_avatar_view"
+                    app:shapeAppearance="@style/CircularImageView"
+                    app:strokeColor="#ffffff"
+                    app:strokeWidth="2dp"
+                    tools:visibility="visible" />
+
+                <org.schabi.newpipe.views.NewPipeTextView
+                    android:id="@+id/channel_title_view"
+                    android:layout_width="0dp"
+                    android:layout_height="wrap_content"
+                    android:layout_marginStart="8dp"
+                    android:layout_marginTop="8dp"
+                    android:layout_marginEnd="4dp"
+                    android:ellipsize="end"
+                    android:lines="1"
+                    android:textAppearance="?android:attr/textAppearanceLarge"
+                    android:textSize="16sp"
+                    app:layout_constraintBottom_toTopOf="@+id/sub_channel_title_view"
+                    app:layout_constraintEnd_toStartOf="@+id/channel_subscribe_button"
+                    app:layout_constraintStart_toEndOf="@+id/channel_avatar_view"
+                    app:layout_constraintTop_toBottomOf="@+id/channel_banner_image"
+                    tools:text="@tools:sample/lorem[10]" />
+
+                <org.schabi.newpipe.views.NewPipeTextView
+                    android:id="@+id/sub_channel_title_view"
+                    android:layout_width="0dp"
+                    android:layout_height="wrap_content"
+                    android:layout_marginStart="8dp"
+                    android:layout_marginEnd="4dp"
+                    android:ellipsize="end"
+                    android:lines="1"
+                    android:textAppearance="?android:attr/textAppearanceLarge"
+                    android:textSize="14sp"
+                    android:visibility="gone"
+                    app:layout_constraintBottom_toTopOf="@+id/channel_subscriber_view"
+                    app:layout_constraintEnd_toStartOf="@+id/channel_subscribe_button"
+                    app:layout_constraintStart_toEndOf="@+id/channel_avatar_view"
+                    app:layout_constraintTop_toBottomOf="@+id/channel_title_view"
+                    tools:text="@tools:sample/lorem[10]"
+                    tools:visibility="visible" />
+
+                <org.schabi.newpipe.views.NewPipeTextView
+                    android:id="@+id/channel_subscriber_view"
+                    android:layout_width="0dp"
+                    android:layout_height="wrap_content"
+                    android:layout_marginStart="8dp"
+                    android:layout_marginTop="2dp"
+                    android:layout_marginEnd="4dp"
+                    android:layout_marginBottom="8dp"
+                    android:textSize="12sp"
+                    app:layout_constraintBottom_toBottomOf="parent"
+                    app:layout_constraintEnd_toStartOf="@+id/channel_subscribe_button"
+                    app:layout_constraintStart_toEndOf="@+id/channel_avatar_view"
+                    app:layout_constraintTop_toBottomOf="@+id/sub_channel_title_view"
+                    tools:text="123,141,411 subscribers" />
+
+                <androidx.appcompat.widget.AppCompatButton
+                    android:id="@+id/channel_subscribe_button"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="@string/subscribe_button_title"
+                    android:textSize="@dimen/channel_rss_title_size"
+                    app:layout_constraintBottom_toBottomOf="parent"
+                    app:layout_constraintEnd_toEndOf="parent"
+                    app:layout_constraintTop_toBottomOf="@+id/channel_banner_image" />
+            </androidx.constraintlayout.widget.ConstraintLayout>
+        </org.schabi.newpipe.views.CustomCollapsingToolbarLayout>
+    </com.google.android.material.appbar.AppBarLayout>
+
+    <RelativeLayout
         android:layout_width="match_parent"
         android:layout_height="match_parent"
-        android:layout_below="@id/tab_layout" />
+        android:layout_below="@id/app_bar_layout"
-
-    <ProgressBar
-        android:id="@+id/loading_progress_bar"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:layout_centerInParent="true"
-        android:indeterminate="true"
-        android:visibility="gone"
-        tools:visibility="visible" />
-
-    <LinearLayout
-        android:id="@+id/empty_state_view"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:layout_centerInParent="true"
         android:orientation="vertical"
-        android:paddingTop="90dp"
+        app:layout_behavior="@string/appbar_scrolling_view_behavior">
-        android:visibility="gone"
-        tools:visibility="visible">
 
-        <org.schabi.newpipe.views.NewPipeTextView
+        <com.google.android.material.tabs.TabLayout
-            android:id="@+id/channel_kaomoji"
+            android:id="@+id/tab_layout"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:background="?attr/colorPrimary"
+            app:tabGravity="fill"
+            app:tabIndicatorColor="@color/white"
+            app:tabMode="scrollable"
+            app:tabRippleColor="@color/white"
+            app:tabTextColor="@color/white" />
+
+        <androidx.viewpager.widget.ViewPager
+            android:id="@+id/view_pager"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:layout_below="@id/tab_layout" />
+
+        <ProgressBar
+            android:id="@+id/loading_progress_bar"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
-            android:layout_gravity="center"
+            android:layout_centerInParent="true"
-            android:layout_marginBottom="10dp"
+            android:indeterminate="true"
-            android:fontFamily="monospace"
+            android:visibility="gone"
-            android:text="(︶︹︺)"
+            tools:visibility="visible" />
-            android:textSize="35sp"
-            tools:ignore="HardcodedText,UnusedAttribute" />
 
-        <org.schabi.newpipe.views.NewPipeTextView
+        <LinearLayout
-            android:id="@+id/error_content_not_supported"
+            android:id="@+id/empty_state_view"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
-            android:layout_marginTop="20dp"
+            android:layout_centerInParent="true"
-            android:text="@string/content_not_supported"
+            android:orientation="vertical"
-            android:textSize="15sp"
+            android:paddingTop="90dp"
-            android:visibility="gone" />
+            android:visibility="gone"
+            tools:visibility="visible">
 
-    </LinearLayout>
+            <org.schabi.newpipe.views.NewPipeTextView
+                android:id="@+id/channel_kaomoji"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_gravity="center"
+                android:layout_marginBottom="10dp"
+                android:fontFamily="monospace"
+                android:text="(︶︹︺)"
+                android:textSize="35sp"
+                tools:ignore="HardcodedText" />
 
-    <!--ERROR PANEL-->
+            <org.schabi.newpipe.views.NewPipeTextView
-    <include
+                android:id="@+id/error_content_not_supported"
-        android:id="@+id/error_panel"
+                android:layout_width="wrap_content"
-        layout="@layout/error_panel"
+                android:layout_height="wrap_content"
-        android:layout_width="wrap_content"
+                android:layout_marginTop="20dp"
-        android:layout_height="wrap_content"
+                android:text="@string/content_not_supported"
-        android:layout_centerInParent="true"
+                android:textSize="15sp"
-        android:layout_marginTop="50dp"
+                android:visibility="gone" />
-        android:visibility="gone"
+
-        tools:visibility="visible" />
+        </LinearLayout>
-</RelativeLayout>
+
+        <!--ERROR PANEL-->
+        <include
+            android:id="@+id/error_panel"
+            layout="@layout/error_panel"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_centerInParent="true"
+            android:layout_marginTop="50dp"
+            android:visibility="gone"
+            tools:visibility="visible" />
+    </RelativeLayout>
+</androidx.coordinatorlayout.widget.CoordinatorLayout>

app/src/main/res/values-land/dimens.xml

@@ -32,7 +32,6 @@
     <dimen name="video_item_detail_sub_channel_text_size">16sp</dimen>
     <dimen name="video_item_detail_upload_date_text_size">14sp</dimen>
     <dimen name="video_item_detail_description_text_size">14sp</dimen>
-    <dimen name="channel_subscribers_text_size">14sp</dimen>
     <dimen name="channel_rss_title_size">14sp</dimen>
     <!-- Elements Size -->
     <dimen name="video_item_detail_uploader_image_size">42dp</dimen>

app/src/main/res/values/dimens.xml

@@ -75,7 +75,6 @@
     <dimen name="video_item_detail_sub_channel_text_size">14sp</dimen>
     <dimen name="video_item_detail_upload_date_text_size">13sp</dimen>
     <dimen name="video_item_detail_description_text_size">13sp</dimen>
-    <dimen name="channel_subscribers_text_size">12sp</dimen>
     <dimen name="channel_rss_title_size">12sp</dimen>
     <!-- Elements Size -->
     <dimen name="video_item_detail_uploader_image_size">32dp</dimen>