[polymer] Rewrite the analysis tab view

tracing/tracing/ui/analysis/analysis_view.html

Index: tracing/tracing/ui/analysis/analysis_view.html
diff --git a/tracing/tracing/ui/analysis/analysis_view.html b/tracing/tracing/ui/analysis/analysis_view.html
index 677ec7a30039941c4e3f7d786da1b0a7f0c60e6b..d5724aa70bc4958577e5870e29acfeae758a94bb 100644
--- a/tracing/tracing/ui/analysis/analysis_view.html
+++ b/tracing/tracing/ui/analysis/analysis_view.html
@@ -79,25 +79,73 @@ using custom elements specialized for different event types.
 (function() {
   var EventRegistry = tr.model.EventRegistry;
 
+  /** Returns the label that goes next to the list of tabs. */
+  function getTabStripLabel(numEvents) {
+    if (numEvents === 0)
+      return 'Nothing selected. Tap stuff.';
+    else if (numEvents === 1)
+      return '1 item selected.';
+    return numEvents + ' items selected.';
+  }
+
+  /**
+   * Returns the tab label for the analysis sub-view associated with the
+   * specified event type and number of events.
+   */
+  function getTabLabel(eventTypeName, numEvents) {
+    var camelLabel = numEvents === 1 ?
+        EventRegistry.getUserFriendlySingularName(eventTypeName) :
+        EventRegistry.getUserFriendlyPluralName(eventTypeName);
+    return camelLabel + ' (' + numEvents + ')';
+  }
+
+  /**
+   * Returns the HTML tag for the analysis sub-view associated with the
+   * specified event type and number of events.
+   */
+  function getSubViewTagName(eventTypeName, numEvents) {
+    var eventTypeInfo =
+        EventRegistry.getEventTypeInfoByTypeName(eventTypeName);
+    return numEvents === 1 ?
+        eventTypeInfo.metadata.singleViewElementName :
+        eventTypeInfo.metadata.multiViewElementName;
+  }
+
+  /**
+   * Returns a new analysis sub-view for the selection and throws an error if no
+   * such sub-view exists.
+   */
+  function createSubView(eventTypeName, selection) {
+    var subView = document.createElement(
+        getSubViewTagName(eventTypeName, selection.length));
+
+    // Unregistered elements with valid names (i.e. names that have a hyphen
+    // in them) inherit from HTMLElement. Unregistered elements with
+    // invalid names inherit from HTMLUnknownElement.
+    if (subView.constructor === HTMLElement ||
+        subView.constructor === HTMLUnknownElement)
+      throw new Error('Element not registered: ' + tagName);
+
+    subView.tabLabel = getTabLabel(eventTypeName, selection.length);
+    subView.selection = selection;
+    return subView;
+  }
+
   Polymer({
     is: 'tr-ui-a-analysis-view',
 
     ready: function() {
-      this.tabView_ = document.createElement('tr-ui-a-tab-view');
-      this.tabView_.style.flex = '1 1 auto';
-      Polymer.dom(this).appendChild(this.tabView_);
       this.brushingStateController_ = undefined;
-      this.onSelectedTabChange_ = this.onSelectedTabChange_.bind(this);
-      this.onSelectionChanged_ = this.onSelectionChanged_.bind(this);
+      this.lastSelection_ = undefined;
+      this.tabView_ = document.createElement('tr-ui-a-tab-view');
+      this.tabView_.addEventListener(
+          'selected-tab-change', this.onSelectedSubViewChanged_.bind(this));
 
-      this.lastSeenSelection_ = new tr.model.EventSet();
+      Polymer.dom(this).appendChild(this.tabView_);
     },
 
     set tallMode(value) {
-      if (value)
-        Polymer.dom(this).classList.add('tall-mode');
-      else
-        Polymer.dom(this).classList.remove('tall-mode');
+      Polymer.dom(this).classList.toggle('tall-mode', value);
     },
 
     get tallMode() {
@@ -113,15 +161,19 @@ using custom elements specialized for different event types.
     },
 
     set brushingStateController(brushingStateController) {
-      if (this.brushingStateController) {
+      if (this.brushingStateController_) {
         this.brushingStateController_.removeEventListener(
-            'change', this.onSelectionChanged_);
+            'change', this.onSelectionChanged_.bind(this));
       }
+
       this.brushingStateController_ = brushingStateController;
       if (this.brushingStateController) {
         this.brushingStateController_.addEventListener(
-            'change', this.onSelectionChanged_);
+          'change', this.onSelectionChanged_.bind(this));
       }
+
+      // The new brushing controller may have a different selection than the
+      // last one, so we have to refresh the subview.
       this.onSelectionChanged_();
     },
 
@@ -130,131 +182,40 @@ using custom elements specialized for different event types.
     },
 
     onSelectionChanged_: function(e) {
-      var selection = this.brushingStateController_.selection;
-
-      var selectionHasSameValue = this.lastSeenSelection_.equals(selection);
-      this.lastSeenSelection_ = selection;
-      if (selectionHasSameValue)
+      if (this.lastSelection_ && this.selection.equals(this.lastSelection_))
         return;
-
-      var lastSelectedTabTagName;
-      var lastSelectedTabTypeName;
-      if (this.tabView_.selectedTab) {
-        lastSelectedTabTagName = this.tabView_.selectedTab.tagName;
-        lastSelectedTabTypeName = this.tabView_.selectedTab._eventTypeName;
-      }
+      this.lastSelection_ = this.selection;
 
       this.tallMode = false;
+      this.tabView_.clearSubViews();
 
-      var previouslySelectedTab = this.tabView_.selectedTab;
-      this.tabView_.removeEventListener(
-        'selected-tab-change', this.onSelectedTabChange_);
-
-      var previousSubViews = {};
-      for (var i = 0; i < Polymer.dom(this.tabView_).children.length; i++) {
-        var previousSubView = Polymer.dom(this.tabView_).children[i];
-        previousSubViews[previousSubView._eventTypeName] = previousSubView;
-      }
-
-      this.tabView_.saveTabStates();
-      Polymer.dom(this.tabView_).textContent = '';
-      if (selection.length == 0) {
-        this.tabView_.tabStripHeadingText = 'Nothing selected. Tap stuff.';
-      } else if (selection.length == 1) {
-        this.tabView_.tabStripHeadingText = '1 item selected: ';
-      } else {
-        this.tabView_.tabStripHeadingText = selection.length +
-            ' items selected: ';
-      }
-
-      var eventsByBaseTypeName = selection.getEventsOrganizedByBaseType(true);
-
-      var numBaseTypesToAnalyze = tr.b.dictionaryLength(eventsByBaseTypeName);
-      for (var eventTypeName in eventsByBaseTypeName) {
-        var subSelection = eventsByBaseTypeName[eventTypeName];
-        var subView = this.createSubViewForSelection_(
-          eventTypeName, subSelection, previousSubViews[eventTypeName]);
-        // Store the eventTypeName for future tab restoration.
-        subView._eventTypeName = eventTypeName;
-        Polymer.dom(this.tabView_).appendChild(subView);
-
-        subView.selection = subSelection;
-      }
-
-      // Restore the tab type that was previously selected. First try by tag
-      // name.
-      var tab;
-      if (lastSelectedTabTagName)
-        tab = Polymer.dom(this.tabView_).querySelector(lastSelectedTabTagName);
-
-      // If that fails, look for a tab with that typeName.
-      if (!tab && lastSelectedTabTypeName) {
-        var tab = tr.b.findFirstInArray(
-            Polymer.dom(this.tabView_).children, function(tab) {
-          return tab._eventTypeName === lastSelectedTabTypeName;
-        });
-      }
-      // If all else fails, pick the first tab.
-      if (!tab)
-        tab = Polymer.dom(this.tabView_).firstChild;
-
-      this.tabView_.selectedTab = tab;
-      this.onSelectedTabChange_();
+      this.tabView_.label = getTabStripLabel(this.selection.length);
+      var eventsByBaseTypeName =
+          this.selection.getEventsOrganizedByBaseType(true);
 
-      this.tabView_.addEventListener(
-        'selected-tab-change', this.onSelectedTabChange_);
+      tr.b.iterItems(eventsByBaseTypeName, function(eventTypeName, events) {
+        var subView = createSubView(eventTypeName, events);
+        this.tabView_.addSubView(subView);
+      }, this);
     },
 
-    createSubViewForSelection_: function(eventTypeName, subSelection,
-        previousSubView) {
-      // Find.
-      var eventTypeInfo = EventRegistry.getEventTypeInfoByTypeName(
-          eventTypeName);
-      var singleMode = subSelection.length == 1;
-      var tagName;
-      if (subSelection.length === 1)
-        tagName = eventTypeInfo.metadata.singleViewElementName;
-      else
-        tagName = eventTypeInfo.metadata.multiViewElementName;
-
-      // if (!tr.ui.b.getPolymerElementNamed(tagName))
-      //   throw new Error('Element not registered: ' + tagName);
+    onSelectedSubViewChanged_: function() {
+      var selectedSubView = this.tabView_.selectedSubView;
 
-      // Create if necessary.
-      var subView;
-      if (previousSubView &&
-          previousSubView.tagName === tagName.toUpperCase())
-        subView = previousSubView;
-      else
-        subView = document.createElement(tagName);
-
-      if (subView.constructor === HTMLElement)
-        throw new Error('Element not registered: ' + tagName);
-      // Set label.
-      var camelLabel;
-      if (subSelection.length === 1)
-        camelLabel = EventRegistry.getUserFriendlySingularName(eventTypeName);
-      else
-        camelLabel = EventRegistry.getUserFriendlyPluralName(eventTypeName);
-      subView.tabLabel = camelLabel + ' (' + subSelection.length + ')';
+      if (!selectedSubView) {
+        this.tallMode = false;
+        this.maybeChangeRelatedEvents_(undefined);
+        return;
+      }
 
-      return subView;
+      this.tallMode = selectedSubView.requiresTallView;
+      this.maybeChangeRelatedEvents_(selectedSubView.relatedEventsToHighlight);
     },
 
-    onSelectedTabChange_: function() {
-      var brushingStateController = this.brushingStateController_;
-      if (this.tabView_.selectedTab) {
-        var selectedTab = this.tabView_.selectedTab;
-        this.tallMode = selectedTab.requiresTallView;
-        if (brushingStateController) {
-          var rlth = selectedTab.relatedEventsToHighlight;
-          brushingStateController.changeAnalysisViewRelatedEvents(rlth);
-        }
-      } else {
-        this.tallMode = false;
-        if (brushingStateController)
-          brushingStateController.changeAnalysisViewRelatedEvents(undefined);
-      }
+    /** Changes the highlighted related events if possible. */
+    maybeChangeRelatedEvents_: function(events) {
+      if (this.brushingStateController)
+        this.brushingStateController.changeAnalysisViewRelatedEvents(events);
     }
   });
 })();