Update ol.Tile

2012-07-10 18:21:54 +02:00
parent 01cb568a50
commit e199fbd7f6
3 changed files with 130 additions and 172 deletions
@@ -0,0 +1,129 @@
+goog.provide('ol.Tile');
+
+goog.require('goog.events');
+goog.require('goog.events.EventTarget');
+goog.require('goog.events.EventType');
+goog.require('ol.TileCoord');
+
+
+/**
+ * @enum {number}
+ */
+ol.TileLoadState = {
+  IDLE: 0,
+  LOADING: 1,
+  LOADED: 2,
+  ERROR: 3
+};
+
+
+
+/**
+ * @constructor
+ * @extends {goog.events.EventTarget}
+ * @param {ol.TileCoord} tileCoord Tile coordinate.
+ * @param {string} src Source.
+ * @param {string=} opt_crossOrigin Cross origin.
+ */
+ol.Tile = function(tileCoord, src, opt_crossOrigin) {
+
+  goog.base(this);
+
+  /**
+   * @type {ol.TileCoord}
+   */
+  this.tileCoord = tileCoord;
+
+  /**
+   * @private
+   * @type {string}
+   */
+  this.src_ = src;
+
+  /**
+   * @private
+   * @type {ol.TileLoadState}
+   */
+  this.state_ = ol.TileLoadState.IDLE;
+
+  /**
+   * @private
+   * @type {Image}
+   */
+  this.image_ = new Image();
+  if (goog.isDef(opt_crossOrigin)) {
+    this.image_.crossOrigin = opt_crossOrigin;
+  }
+
+  /**
+   * @private
+   * @type {Array.<number>}
+   */
+  this.imageListenerKeys_ = null;
+
+};
+goog.inherits(ol.Tile, goog.events.EventTarget);
+
+
+/**
+ * @return {Image} Image.
+ */
+ol.Tile.prototype.getImage = function() {
+  return this.image_;
+};
+
+
+/**
+ * @private
+ */
+ol.Tile.prototype.handleImageError_ = function() {
+  this.state_ = ol.TileLoadState.ERROR;
+  this.unlistenImage_();
+};
+
+
+/**
+ * @private
+ */
+ol.Tile.prototype.handleImageLoad_ = function() {
+  this.state_ = ol.TileLoadState.LOADED;
+  this.unlistenImage_();
+};
+
+
+/**
+ * @return {boolean} Is loaded.
+ */
+ol.Tile.prototype.isLoaded = function() {
+  return this.state_ == ol.TileLoadState.LOADED;
+};
+
+
+/**
+ * @return {EventTarget} Event target.
+ */
+ol.Tile.prototype.load = function() {
+  if (this.state_ == ol.TileLoadState.IDLE) {
+    this.state_ = ol.TileLoadState.LOADING;
+    goog.asserts.assert(goog.isNull(this.imageListenerKeys_));
+    this.imageListenerKeys_ = [
+      goog.events.listenOnce(this.image_, goog.events.EventType.ERROR,
+          this.handleImageError_, false, this),
+      goog.events.listenOnce(this.image_, goog.events.EventType.LOAD,
+          this.handleImageLoad_, false, this)
+    ];
+    this.image_.src = this.src_;
+  }
+  return this.image_;
+};
+
+
+/**
+ * @private
+ */
+ol.Tile.prototype.unlistenImage_ = function() {
+  goog.asserts.assert(!goog.isNull(this.imageListenerKeys_));
+  goog.array.forEach(this.imageListenerKeys_, goog.events.unlistenByKey);
+  this.imageListenerKeys_ = null;
+};
+