Merge pull request #5051 from fredj/remove_aborted_tiles

Handle aborted tiles in ol.TileQueue

src/ol/imagetile.js

@@ -72,6 +72,8 @@ ol.ImageTile.prototype.disposeInternal = function() {
   if (this.interimTile) {
     this.interimTile.dispose();
   }
+  this.state = ol.TileState.ABORT;
+  this.changed();
   goog.base(this, 'disposeInternal');
 };
 

src/ol/tile.js

@@ -15,7 +15,8 @@ ol.TileState = {
   LOADING: 1,
   LOADED: 2,
   ERROR: 3,
-  EMPTY: 4
+  EMPTY: 4,
+  ABORT: 5
 };
 
 

src/ol/tilequeue.js

@@ -1,6 +1,7 @@
 goog.provide('ol.TilePriorityFunction');
 goog.provide('ol.TileQueue');
 
+goog.require('goog.asserts');
 goog.require('ol.events');
 goog.require('ol.events.EventType');
 goog.require('ol.Coordinate');
@@ -56,7 +57,7 @@ ol.TileQueue = function(tilePriorityFunction, tileChangeCallback) {
 
   /**
    * @private
-   * @type {Object.<string,boolean>}
+   * @type {!Object.<string,boolean>}
    */
   this.tilesLoadingKeys_ = {};
 
@@ -94,7 +95,7 @@ ol.TileQueue.prototype.handleTileChange = function(event) {
   var tile = /** @type {ol.Tile} */ (event.target);
   var state = tile.getState();
   if (state === ol.TileState.LOADED || state === ol.TileState.ERROR ||
-      state === ol.TileState.EMPTY) {
+      state === ol.TileState.EMPTY || state === ol.TileState.ABORT) {
     ol.events.unlisten(tile, ol.events.EventType.CHANGE,
         this.handleTileChange, this);
     var tileKey = tile.getKey();
@@ -104,6 +105,7 @@ ol.TileQueue.prototype.handleTileChange = function(event) {
     }
     this.tileChangeCallback_();
   }
+  goog.asserts.assert(Object.keys(this.tilesLoadingKeys_).length === this.tilesLoading_);
 };
 
 
@@ -113,15 +115,17 @@ ol.TileQueue.prototype.handleTileChange = function(event) {
  */
 ol.TileQueue.prototype.loadMoreTiles = function(maxTotalLoading, maxNewLoads) {
   var newLoads = 0;
-  var tile;
+  var tile, tileKey;
   while (this.tilesLoading_ < maxTotalLoading && newLoads < maxNewLoads &&
          this.getCount() > 0) {
     tile = /** @type {ol.Tile} */ (this.dequeue()[0]);
-    if (tile.getState() === ol.TileState.IDLE) {
+    tileKey = tile.getKey();
-      this.tilesLoadingKeys_[tile.getKey()] = true;
+    if (tile.getState() === ol.TileState.IDLE && !(tileKey in this.tilesLoadingKeys_)) {
+      this.tilesLoadingKeys_[tileKey] = true;
       ++this.tilesLoading_;
       ++newLoads;
       tile.load();
     }
+    goog.asserts.assert(Object.keys(this.tilesLoadingKeys_).length === this.tilesLoading_);
   }
 };

test/spec/ol/tilequeue.test.js

@@ -14,15 +14,16 @@ describe('ol.TileQueue', function() {
   }
 
   var tileId = 0;
-  function createImageTile() {
+  function createImageTile(opt_tileLoadFunction) {
     ++tileId;
     var tileCoord = [tileId, tileId, tileId];
     var state = ol.TileState.IDLE;
     var src = 'data:image/gif;base64,R0lGODlhAQABAPAAAP8AAP///' +
         'yH5BAAAAAAALAAAAAABAAEAAAICRAEAOw==#' + tileId;
 
-    return new ol.ImageTile(tileCoord, state, src, null,
+    var tileLoadFunction = opt_tileLoadFunction ?
-        ol.source.Image.defaultImageLoadFunction);
+        opt_tileLoadFunction : ol.source.Image.defaultImageLoadFunction;
+    return new ol.ImageTile(tileCoord, state, src, null, tileLoadFunction);
   }
 
   describe('#loadMoreTiles()', function() {
@@ -121,11 +122,47 @@ describe('ol.TileQueue', function() {
 
     });
   });
+
+  describe('tile change event', function() {
+    var noop = function() {};
+
+    it('abort queued tiles', function() {
+      var tq = new ol.TileQueue(noop, noop);
+      var tile = createImageTile();
+      expect(tile.hasListener(ol.events.EventType.CHANGE)).to.be(false);
+
+      tq.enqueue([tile]);
+      expect(tile.hasListener(ol.events.EventType.CHANGE)).to.be(true);
+
+      tile.dispose();
+      expect(tile.hasListener(ol.events.EventType.CHANGE)).to.be(false);
+      expect(tile.getState()).to.eql(ol.TileState.ABORT);
+    });
+
+    it('abort loading tiles', function() {
+      var tq = new ol.TileQueue(noop, noop);
+      var tile = createImageTile(noop);
+
+      tq.enqueue([tile]);
+      tq.loadMoreTiles(Infinity, Infinity);
+      expect(tq.getTilesLoading()).to.eql(1);
+      expect(tile.getState()).to.eql(ol.TileState.LOADING);
+
+      tile.dispose();
+      expect(tq.getTilesLoading()).to.eql(0);
+      expect(tile.hasListener(ol.events.EventType.CHANGE)).to.be(false);
+      expect(tile.getState()).to.eql(ol.TileState.ABORT);
+
+    });
+
+  });
+
 });
 
 goog.require('ol.ImageTile');
 goog.require('ol.Tile');
 goog.require('ol.TileState');
 goog.require('ol.TileQueue');
+goog.require('ol.events.EventType');
 goog.require('ol.source.Image');
 goog.require('ol.structs.PriorityQueue');