Changeset 2572

Timestamp:

02/13/13 08:49:29 (11 years ago)

Author:

twagoo

Message:

Prevented loading of component XML until XML tab is actually selected. Also truncated large XML content to prevent plugin/browser hangs and crashes. [Fixes #268]

Location:

ComponentRegistry/trunk/ComponentBrowserGui/src/main/flex/clarin/cmdi/componentregistry/browser

Files:

• infoPage.mxml (modified) (5 diffs)
• xmlPanel.mxml (modified) (2 diffs)

ComponentRegistry/trunk/ComponentBrowserGui/src/main/flex/clarin/cmdi/componentregistry/browser/infoPage.mxml

@@ -23 +23 @@
                                   height="100%"
                                   width="100%"
-                                  styleName="borderStyles">
+                                  styleName="borderStyles"
+                                  change="infoViewStack_changeHandler(event)"
+                                  >
 
                 <browser:xmlBrowsePanel id="viewPanel"
@@ -29 +31 @@
                                                                 cmdComponent="{cmdComponent}"
                                                                 itemDescription="{_itemDescription}"/>
+                
                 <browser:xmlPanel id="xmlPanel"
                                                   label="xml"
                                                   cmdComponent="{cmdComponent}"/>
+                
                 <browser:CommentsPanel id="commentsPanel"
                                                            label="{commentsLabel}"
@@ -46 +50 @@
                         
                         import mx.events.FlexEvent;
+                        import mx.events.IndexChangedEvent;
+                        import mx.messaging.SubscriptionInfo;
                         
                         [Bindable]
@@ -54 +60 @@
                                         infoViewStack.selectedChild = viewPanel;
                                 } else if(startupPanel == Config.BROWSER_PANEL_XML) {                                   
-                                        infoViewStack.selectedChild = xmlPanel;
+                                        //infoViewStack.selectedChild = xmlPanel;
                                 } else if(startupPanel == Config.BROWSER_PANEL_COMMENTS) {
                                         infoViewStack.selectedChild = commentsPanel;
@@ -77 +83 @@
                         }
 
+                        protected function infoViewStack_changeHandler(event:IndexChangedEvent):void
+                        {
+                                xmlPanel.updateCmdComponentText();
+                        }
+
                 ]]>
         </mx:Script>

ComponentRegistry/trunk/ComponentBrowserGui/src/main/flex/clarin/cmdi/componentregistry/browser/xmlPanel.mxml

@@ -3 +3 @@
                  xmlns:comp="clarin.cmdi.componentregistry.common.components.*">
 
-        <mx:XML id="cmdComponent"/>
         <comp:ScrollableTextArea id="infoTextArea"
                                                          styleName="xmlTextArea"
                                                          editable="false"
-                                                         text="{cmdComponent}"
                                                          width="100%"
                                                          height="100%"
@@ -13 +11 @@
                                                          paddingTop="5"
                                                          />
+        
+        <mx:Script>
+                <!-- 
+                        The code below assures lazy loading of the component XML into the scrollable text area. 
+                        Large component specifications can cause the application to hang or even crash the browser, 
+                        see <https://trac.clarin.eu/ticket/268>
+                -->
+                <![CDATA[
+                        import mx.containers.ViewStack;
+                        import mx.core.Application;
+                        private var componentXML:XML;
+                        private var MAX_XML_LENGTH:int = 10000;
+                        
+                        public function set cmdComponent(xml:XML):void {
+                                if(this.componentXML != xml){
+                                        this.componentXML = xml;
+                                        updateCmdComponentText();
+                                }
+                        }
+                        
+                        public function updateCmdComponentText():void {
+                                // Only forward the XML to the text area if the XML panel is the selected view 
+                                if(isSelectedView()){
+                                        var xmlText:String = componentXML.toXMLString();
+                                        if(xmlText.length > MAX_XML_LENGTH + 3){
+                                                // XML too lengthy, truncate (otherwise we run into performance issues)
+                                                infoTextArea.text = xmlText.substr(0, MAX_XML_LENGTH) + "...\n\nSpecification too large to display. Download XML to see the entire specification.";
+                                        } else{
+                                                infoTextArea.text = xmlText;
+                                        }
+                                }
+                        }
+                        
+                        private function isSelectedView():Boolean
+                        {
+                                var obj:DisplayObject = this;
+                                // Whole chain until application root should be visible
+                                while (obj && obj !== Application.application)
+                                {
+                                        // Special case: viewstack - this item should be the selected item
+                                        if(obj.parent is ViewStack){
+                                                return ViewStack(obj.parent).selectedChild == obj;
+                                        }
+                                        
+                                        obj = obj.parent;
+                                }
+                                return true;
+                        }
+                ]]>
+        </mx:Script>
 </mx:VBox>