The Tor Browser: browser/components/customizableui/src/PanelWideWidgetTracker.jsm@8bccb770b82d (annotated)

browser/components/customizableui/src/PanelWideWidgetTracker.jsm@8bccb770b82d (annotated)

browser/components/customizableui/src/PanelWideWidgetTracker.jsm

Wed, 31 Dec 2014 13:27:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 13:27:57 +0100
branch: TOR_BUG_3246
changeset 6: 8bccb770b82d
permissions: -rw-r--r--

Ignore runtime configuration files generated during quality assurance.

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 const {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;
 this.EXPORTED_SYMBOLS = ["PanelWideWidgetTracker"];
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "CustomizableUI",
   "resource:///modules/CustomizableUI.jsm");
 let gModuleName = "[PanelWideWidgetTracker]";
 #include logging.js
 let gPanel = CustomizableUI.AREA_PANEL;
 // We keep track of the widget placements for the panel locally:
 let gPanelPlacements = [];
 // All the wide widgets we know of:
 let gWideWidgets = new Set();
 // All the widgets we know of:
 let gSeenWidgets = new Set();
 let PanelWideWidgetTracker = {
   // Listeners used to validate panel contents whenever they change:
   onWidgetAdded: function(aWidgetId, aArea, aPosition) {
     if (aArea == gPanel) {
       gPanelPlacements = CustomizableUI.getWidgetIdsInArea(gPanel);
       let moveForward = this.shouldMoveForward(aWidgetId, aPosition);
       this.adjustWidgets(aWidgetId, moveForward);
     }
   },
   onWidgetMoved: function(aWidgetId, aArea, aOldPosition, aNewPosition) {
     if (aArea == gPanel) {
       gPanelPlacements = CustomizableUI.getWidgetIdsInArea(gPanel);
       let moveForward = this.shouldMoveForward(aWidgetId, aNewPosition);
       this.adjustWidgets(aWidgetId, moveForward);
     }
   },
   onWidgetRemoved: function(aWidgetId, aPrevArea) {
     if (aPrevArea == gPanel) {
       gPanelPlacements = CustomizableUI.getWidgetIdsInArea(gPanel);
       let pos = gPanelPlacements.indexOf(aWidgetId);
       this.adjustWidgets(aWidgetId, false);
     }
   },
   onWidgetReset: function(aWidgetId) {
     gPanelPlacements = CustomizableUI.getWidgetIdsInArea(gPanel);
   },
   // Listener to keep abreast of any new nodes. We use the DOM one because
   // we need access to the actual node's classlist, so we can't use the ones above.
   // Furthermore, onWidgetCreated only fires for API-based widgets, not for XUL ones.
   onWidgetAfterDOMChange: function(aNode, aNextNode, aContainer) {
     if (!gSeenWidgets.has(aNode.id)) {
       if (aNode.classList.contains(CustomizableUI.WIDE_PANEL_CLASS)) {
         gWideWidgets.add(aNode.id);
       }
       gSeenWidgets.add(aNode.id);
     }
   },
   // When widgets get destroyed, we remove them from our sets of stuff we care about:
   onWidgetDestroyed: function(aWidgetId) {
     gSeenWidgets.delete(aWidgetId);
     gWideWidgets.delete(aWidgetId);
   },
   shouldMoveForward: function(aWidgetId, aPosition) {
     let currentWidgetAtPosition = gPanelPlacements[aPosition + 1];
     let rv = gWideWidgets.has(currentWidgetAtPosition) && !gWideWidgets.has(aWidgetId);
     // We might now think we can move forward, but for that we need at least 2 more small
     // widgets to be present:
     if (rv) {
       let furtherWidgets = gPanelPlacements.slice(aPosition + 2);
       let realWidgets = 0;
       if (furtherWidgets.length >= 2) {
         while (furtherWidgets.length && realWidgets < 2) {
           let w = furtherWidgets.shift();
           if (!gWideWidgets.has(w) && this.checkWidgetStatus(w)) {
             realWidgets++;
           }
         }
       }
       if (realWidgets < 2) {
         rv = false;
       }
     }
     return rv;
   },
   adjustWidgets: function(aWidgetId, aMoveForwards) {
     if (this.adjusting) {
       return;
     }
     this.adjusting = true;
     let widgetsAffected = [w for (w of gPanelPlacements) if (gWideWidgets.has(w))];
     // If we're moving the wide widgets forwards (down/to the right in the panel)
     // we want to start with the last widgets. Otherwise we move widgets over other wide
     // widgets, which might mess up their order. Likewise, if moving backwards we should start with
     // the first widget and work our way down/right from there.
     let compareFn = aMoveForwards ? (function(a, b) a < b) : (function(a, b) a > b)
     widgetsAffected.sort(function(a, b) compareFn(gPanelPlacements.indexOf(a),
                                                   gPanelPlacements.indexOf(b)));
     for (let widget of widgetsAffected) {
       this.adjustPosition(widget, aMoveForwards);
     }
     this.adjusting = false;
   },
   // This function is called whenever an item gets moved in the menu panel. It
   // adjusts the position of widgets within the panel to prevent "gaps" between
   // wide widgets that could be filled up with single column widgets
   adjustPosition: function(aWidgetId, aMoveForwards) {
     // Make sure that there are n % columns = 0 narrow buttons before the widget.
     let placementIndex = gPanelPlacements.indexOf(aWidgetId);
     let prevSiblingCount = 0;
     let fixedPos = null;
     while (placementIndex--) {
       let thisWidgetId = gPanelPlacements[placementIndex];
       if (gWideWidgets.has(thisWidgetId)) {
         continue;
       }
       let widgetStatus = this.checkWidgetStatus(thisWidgetId);
       if (!widgetStatus) {
         continue;
       }
       if (widgetStatus == "public-only") {
         fixedPos = !fixedPos ? placementIndex : Math.min(fixedPos, placementIndex);
         prevSiblingCount = 0;
       } else {
         prevSiblingCount++;
       }
     }
     if (fixedPos !== null || prevSiblingCount % CustomizableUI.PANEL_COLUMN_COUNT) {
       let desiredPos = (fixedPos !== null) ? fixedPos : gPanelPlacements.indexOf(aWidgetId);
       let desiredChange = -(prevSiblingCount % CustomizableUI.PANEL_COLUMN_COUNT);
       if (aMoveForwards && fixedPos == null) {
         // +1 because otherwise we'd count ourselves:
         desiredChange = CustomizableUI.PANEL_COLUMN_COUNT + desiredChange + 1;
       }
       desiredPos += desiredChange;
       CustomizableUI.moveWidgetWithinArea(aWidgetId, desiredPos);
     }
   },
   /*
    * Check whether a widget id is actually known anywhere.
    * @returns false if the widget doesn't exist,
    *          "public-only" if it's not shown in private windows
    *          "real" if it does exist and is shown even in private windows
    */
   checkWidgetStatus: function(aWidgetId) {
     let widgetWrapper = CustomizableUI.getWidget(aWidgetId);
     // This widget might not actually exist:
     if (!widgetWrapper) {
       return false;
     }
     // This widget might still not actually exist:
     if (widgetWrapper.provider == CustomizableUI.PROVIDER_XUL &&
         widgetWrapper.instances.length == 0) {
       return false;
     }
     // Or it might only be there some of the time:
     if (widgetWrapper.provider == CustomizableUI.PROVIDER_API &&
         widgetWrapper.showInPrivateBrowsing === false) {
       return "public-only";
     }
     return "real";
   },
   init: function() {
     // Initialize our local placements copy and register the listener
     gPanelPlacements = CustomizableUI.getWidgetIdsInArea(gPanel);
     CustomizableUI.addListener(this);
   },
 };

The Tor Browser / annotate

browser/components/customizableui/src/PanelWideWidgetTracker.jsm@8bccb770b82d (annotated)

browser/components/customizableui/src/PanelWideWidgetTracker.jsm