Improve View Widget Refreshing (#8135)

* Update view.js

* add viewhandler base class and view subclasses

* simplify render methods of wikified views

* use fakewidget's text for rendering

* simplify wikified refresh methods

* remove unneeded self=this

* pass mode to makeTranscludeWidget

* update view widget

* update view widget

core/modules/widgets/view.js

@@ -18,6 +18,89 @@ var ViewWidget = function(parseTreeNode,options) {
 	this.initialise(parseTreeNode,options);
 };
 
+var ViewHandler = function(widget) {
+	this.wiki = widget.wiki;
+	this.widget = widget;
+	this.document = widget.document;
+};
+
+/*
+Base ViewHandler render method
+*/
+ViewHandler.prototype.render = function(parent,nextSibling) {
+	this.text = this.getValue();
+	this.createTextNode(parent,nextSibling);
+};
+
+/*
+Base ViewHandler render method for wikified views
+*/
+ViewHandler.prototype.renderWikified = function(parent,nextSibling) {
+	this.createFakeWidget();
+	this.text = this.getValue();
+	this.createWikifiedTextNode(parent,nextSibling);
+};
+
+/*
+ViewHandler method to create a simple text node
+*/
+ViewHandler.prototype.createTextNode = function(parent,nextSibling) {
+	if(this.text) {
+		var textNode = this.document.createTextNode(this.text);
+		parent.insertBefore(textNode,nextSibling);
+		this.widget.domNodes.push(textNode);
+	} else {
+		this.widget.makeChildWidgets();
+		this.widget.renderChildren(parent,nextSibling);
+	}
+};
+
+/*
+ViewHandler method to always create a text node, even if there's no text
+*/
+ViewHandler.prototype.createWikifiedTextNode = function(parent,nextSibling) {
+	var textNode = this.document.createTextNode(this.text || "");
+	parent.insertBefore(textNode,nextSibling);
+	this.widget.domNodes.push(textNode);
+};
+
+/*
+ViewHandler method to create a fake widget used by wikified views
+*/
+ViewHandler.prototype.createFakeWidget = function() {
+	this.fakeWidget = this.wiki.makeTranscludeWidget(this.widget.viewTitle,{
+		document: $tw.fakeDocument,
+		field: this.widget.viewField,
+		index: this.widget.viewIndex,
+		parseAsInline: this.widget.viewMode !== "block",
+		mode: this.widget.viewMode === "block" ? "block" : "inline",
+		parentWidget: this.widget,
+		subTiddler: this.widget.viewSubTiddler
+	});
+	this.fakeNode = $tw.fakeDocument.createElement("div");
+	this.fakeWidget.makeChildWidgets();
+	this.fakeWidget.render(this.fakeNode,null);
+};
+
+ViewHandler.prototype.refreshWikified = function(changedTiddlers) {
+	var refreshed = this.fakeWidget.refresh(changedTiddlers);
+	if(refreshed) {
+		var newText = this.getValue();
+		if(newText !== this.text) {
+			this.widget.domNodes[0].textContent = newText;
+			this.text = newText;
+		}
+	}
+	return refreshed;
+};
+
+/*
+Base ViewHandler refresh method
+*/
+ViewHandler.prototype.refresh = function(changedTiddlers) {
+	return false;
+};
+
 /*
 Inherit from the base widget class
 */
@@ -30,14 +113,8 @@ ViewWidget.prototype.render = function(parent,nextSibling) {
 	this.parentDomNode = parent;
 	this.computeAttributes();
 	this.execute();
-	if(this.text) {
+	this.view = this.getView(this.viewFormat);
-		var textNode = this.document.createTextNode(this.text);
+	this.view.render(parent,nextSibling);
-		parent.insertBefore(textNode,nextSibling);
-		this.domNodes.push(textNode);
-	} else {
-		this.makeChildWidgets();
-		this.renderChildren(parent,nextSibling);
-	}
 };
 
 /*
@@ -52,49 +129,238 @@ ViewWidget.prototype.execute = function() {
 	this.viewFormat = this.getAttribute("format","text");
 	this.viewTemplate = this.getAttribute("template","");
 	this.viewMode = this.getAttribute("mode","block");
-	switch(this.viewFormat) {
-		case "htmlwikified":
-			this.text = this.getValueAsHtmlWikified(this.viewMode);
-			break;
-		case "plainwikified":
-			this.text = this.getValueAsPlainWikified(this.viewMode);
-			break;
-		case "htmlencodedplainwikified":
-			this.text = this.getValueAsHtmlEncodedPlainWikified(this.viewMode);
-			break;
-		case "htmlencoded":
-			this.text = this.getValueAsHtmlEncoded();
-			break;
-		case "htmltextencoded":
-			this.text = this.getValueAsHtmlTextEncoded();
-			break;
-		case "urlencoded":
-			this.text = this.getValueAsUrlEncoded();
-			break;
-		case "doubleurlencoded":
-			this.text = this.getValueAsDoubleUrlEncoded();
-			break;
-		case "date":
-			this.text = this.getValueAsDate(this.viewTemplate);
-			break;
-		case "relativedate":
-			this.text = this.getValueAsRelativeDate();
-			break;
-		case "stripcomments":
-			this.text = this.getValueAsStrippedComments();
-			break;
-		case "jsencoded":
-			this.text = this.getValueAsJsEncoded();
-			break;
-		default: // "text"
-			this.text = this.getValueAsText();
-			break;
-	}
 };
 
 /*
-The various formatter functions are baked into this widget for the moment. Eventually they will be replaced by macro functions
+Initialise the view subclasses
 */
+ViewWidget.prototype.getView = function(format) {
+	var View = this.initialiseView();
+	View.prototype = Object.create(ViewHandler.prototype);
+	switch(format) {
+		case "htmlwikified":
+			View = this.initialiseHTMLWikifiedView(View);
+			break;
+		case "plainwikified":
+			View = this.initialisePlainWikifiedView(View);
+			break;
+		case "htmlencodedplainwikified":
+			View = this.initialiseHTMLEncodedPlainWikifiedView(View);
+			break;
+		case "htmlencoded":
+			View = this.initialiseHTMLEncodedView(View);
+			break;
+		case "htmltextencoded":
+			View = this.initialiseHTMLTextEncodedView(View);
+			break;
+		case "urlencoded":
+			View = this.initialiseURLEncodedView(View);
+			break;
+		case "doubleurlencoded":
+			View = this.initialiseDoubleURLEncodedView(View);
+			break;
+		case "date":
+			View = this.initialiseDateView(View);
+			break;
+		case "relativedate":
+			View = this.initialiseRelativeDateView(View);
+			break;
+		case "stripcomments":
+			View = this.initialiseStripCommentsView(View);
+			break;
+		case "jsencoded":
+			View = this.initialiseJSEncodedView(View);
+			break;
+		default: // "text"
+			View = this.initialiseTextView(View);
+			break;
+	};
+	return new View(this);
+};
+
+/*
+Return the function to intitialise the view subclass
+*/
+ViewWidget.prototype.initialiseView = function() {
+	return function(widget) {
+		ViewHandler.call(this,widget);
+	};
+};
+
+/*
+Initialise HTML wikified view methods
+*/
+ViewWidget.prototype.initialiseHTMLWikifiedView = function(View) {
+
+	View.prototype.render = function(parent,nextSibling) {
+		this.renderWikified(parent,nextSibling);
+	};
+
+	View.prototype.getValue = function() {
+		return this.fakeNode.innerHTML;
+	};
+
+	View.prototype.refresh = function(changedTiddlers) {
+		return this.refreshWikified(changedTiddlers);
+	};
+	return View;
+};
+
+/*
+Initialise plain wikified view methods
+*/
+ViewWidget.prototype.initialisePlainWikifiedView = function(View) {
+
+	View.prototype.render = function(parent,nextSibling) {
+		this.renderWikified(parent,nextSibling);
+	};
+
+	View.prototype.getValue = function() {
+		return this.fakeNode.textContent;
+	};
+
+	View.prototype.refresh = function(changedTiddlers) {
+		return this.refreshWikified(changedTiddlers);
+	};
+	return View;
+};
+
+/*
+Initialise HTML encoded plain wikified methods
+*/
+ViewWidget.prototype.initialiseHTMLEncodedPlainWikifiedView = function(View) {
+	
+	View.prototype.render = function(parent,nextSibling) {
+		this.renderWikified(parent,nextSibling);
+	};
+
+	View.prototype.getValue = function() {
+		return $tw.utils.htmlEncode(this.fakeNode.textContent);
+	};
+
+	View.prototype.refresh = function(changedTiddlers) {
+		return this.refreshWikified(changedTiddlers);
+	};
+	return View;
+};
+
+/*
+Initialise HTML encoded mehods
+*/
+ViewWidget.prototype.initialiseHTMLEncodedView = function(View) {
+	var self = this;
+	View.prototype.getValue = function() {
+		return $tw.utils.htmlEncode(self.getValueAsText());
+	};
+	return View;
+};
+
+/*
+Initialise HTML text encoded mehods
+*/
+ViewWidget.prototype.initialiseHTMLTextEncodedView = function(View) {
+	var self = this;
+	View.prototype.getValue = function() {
+		return $tw.utils.htmlTextEncode(self.getValueAsText());
+	};
+	return View;
+};
+
+/*
+Initialise URL encoded mehods
+*/
+ViewWidget.prototype.initialiseURLEncodedView = function(View) {
+	var self = this;
+	View.prototype.getValue = function() {
+		return $tw.utils.encodeURIComponentExtended(self.getValueAsText());
+	};
+	return View;
+};
+
+/*
+Initialise double URL encoded mehods
+*/
+ViewWidget.prototype.initialiseDoubleURLEncodedView = function(View) {
+	var self = this;
+	View.prototype.getValue = function() {
+		return $tw.utils.encodeURIComponentExtended($tw.utils.encodeURIComponentExtended(self.getValueAsText()));
+	};
+	return View;
+};
+
+/*
+Initialise date mehods
+*/
+ViewWidget.prototype.initialiseDateView = function(View) {
+	var self = this;
+	View.prototype.getValue = function(format) {
+		format = format || "YYYY MM DD 0hh:0mm";
+		var value = $tw.utils.parseDate(self.getValue());
+		if(value && $tw.utils.isDate(value) && value.toString() !== "Invalid Date") {
+			return $tw.utils.formatDateString(value,format);
+		} else {
+			return "";
+		}
+	};
+	return View;
+};
+
+/*
+Initialise relative date mehods
+*/
+ViewWidget.prototype.initialiseRelativeDateView = function(View) {
+	var self = this;
+	View.prototype.getValue = function(format) {
+		var value = $tw.utils.parseDate(self.getValue());
+		if(value && $tw.utils.isDate(value) && value.toString() !== "Invalid Date") {
+			return $tw.utils.getRelativeDate((new Date()) - (new Date(value))).description;
+		} else {
+			return "";
+		}
+	};
+	return View;
+};
+
+/*
+Initialise stripcomments mehods
+*/
+ViewWidget.prototype.initialiseStripCommentsView = function(View) {
+	var self = this;
+	View.prototype.getValue = function() {
+		var lines = self.getValueAsText().split("\n"),
+			out = [];
+		for(var line=0; line<lines.length; line++) {
+			var text = lines[line];
+			if(!/^\s*\/\/#/.test(text)) {
+				out.push(text);
+			}
+		}
+		return out.join("\n");
+	};
+	return View;
+};
+
+/*
+Initialise JS encoded mehods
+*/
+ViewWidget.prototype.initialiseJSEncodedView = function(View) {
+	var self = this;
+	View.prototype.getValue = function() {
+		return $tw.utils.stringify(self.getValueAsText());
+	};
+	return View;
+};
+
+/*
+Initialise text mehods
+*/
+ViewWidget.prototype.initialiseTextView = function(View) {
+	var self = this;
+	View.prototype.getValue = function() {
+		return self.getValueAsText();
+	};
+	return View;
+};
 
 /*
 Retrieve the value of the widget. Options are:
@@ -138,78 +404,6 @@ ViewWidget.prototype.getValueAsText = function() {
 	return this.getValue({asString: true});
 };
 
-ViewWidget.prototype.getValueAsHtmlWikified = function(mode) {
-	return this.wiki.renderText("text/html","text/vnd.tiddlywiki",this.getValueAsText(),{
-		parseAsInline: mode !== "block",
-		parentWidget: this
-	});
-};
-
-ViewWidget.prototype.getValueAsPlainWikified = function(mode) {
-	return this.wiki.renderText("text/plain","text/vnd.tiddlywiki",this.getValueAsText(),{
-		parseAsInline: mode !== "block",
-		parentWidget: this
-	});
-};
-
-ViewWidget.prototype.getValueAsHtmlEncodedPlainWikified = function(mode) {
-	return $tw.utils.htmlEncode(this.wiki.renderText("text/plain","text/vnd.tiddlywiki",this.getValueAsText(),{
-		parseAsInline: mode !== "block",
-		parentWidget: this
-	}));
-};
-
-ViewWidget.prototype.getValueAsHtmlEncoded = function() {
-	return $tw.utils.htmlEncode(this.getValueAsText());
-};
-
-ViewWidget.prototype.getValueAsHtmlTextEncoded = function() {
-	return $tw.utils.htmlTextEncode(this.getValueAsText());
-};
-
-ViewWidget.prototype.getValueAsUrlEncoded = function() {
-	return $tw.utils.encodeURIComponentExtended(this.getValueAsText());
-};
-
-ViewWidget.prototype.getValueAsDoubleUrlEncoded = function() {
-	return $tw.utils.encodeURIComponentExtended($tw.utils.encodeURIComponentExtended(this.getValueAsText()));
-};
-
-ViewWidget.prototype.getValueAsDate = function(format) {
-	format = format || "YYYY MM DD 0hh:0mm";
-	var value = $tw.utils.parseDate(this.getValue());
-	if(value && $tw.utils.isDate(value) && value.toString() !== "Invalid Date") {
-		return $tw.utils.formatDateString(value,format);
-	} else {
-		return "";
-	}
-};
-
-ViewWidget.prototype.getValueAsRelativeDate = function(format) {
-	var value = $tw.utils.parseDate(this.getValue());
-	if(value && $tw.utils.isDate(value) && value.toString() !== "Invalid Date") {
-		return $tw.utils.getRelativeDate((new Date()) - (new Date(value))).description;
-	} else {
-		return "";
-	}
-};
-
-ViewWidget.prototype.getValueAsStrippedComments = function() {
-	var lines = this.getValueAsText().split("\n"),
-		out = [];
-	for(var line=0; line<lines.length; line++) {
-		var text = lines[line];
-		if(!/^\s*\/\/#/.test(text)) {
-			out.push(text);
-		}
-	}
-	return out.join("\n");
-};
-
-ViewWidget.prototype.getValueAsJsEncoded = function() {
-	return $tw.utils.stringify(this.getValueAsText());
-};
-
 /*
 Selectively refreshes the widget if needed. Returns true if the widget or any of its children needed re-rendering
 */
@@ -219,7 +413,7 @@ ViewWidget.prototype.refresh = function(changedTiddlers) {
 		this.refreshSelf();
 		return true;
 	} else {
-		return false;
+		return this.view.refresh(changedTiddlers);
 	}
 };