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openlayers

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Build tools and sources for developing OpenLayers based mapping applications

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goog.provide('ol.ImageTile'); goog.require('ol'); goog.require('ol.Tile'); goog.require('ol.events'); goog.require('ol.events.EventType'); /** * @constructor * @extends {ol.Tile} * @param {ol.TileCoord} tileCoord Tile coordinate. * @param {ol.Tile.State} state State. * @param {string} src Image source URI. * @param {?string} crossOrigin Cross origin. * @param {ol.TileLoadFunctionType} tileLoadFunction Tile load function. */ ol.ImageTile = function(tileCoord, state, src, crossOrigin, tileLoadFunction) { ol.Tile.call(this, tileCoord, state); /** * Image URI * * @private * @type {string} */ this.src_ = src; /** * @private * @type {Image} */ this.image_ = new Image(); if (crossOrigin !== null) { this.image_.crossOrigin = crossOrigin; } /** * @private * @type {Array.<ol.EventsKey>} */ this.imageListenerKeys_ = null; /** * @private * @type {ol.TileLoadFunctionType} */ this.tileLoadFunction_ = tileLoadFunction; }; ol.inherits(ol.ImageTile, ol.Tile); /** * @inheritDoc */ ol.ImageTile.prototype.disposeInternal = function() { if (this.state == ol.Tile.State.LOADING) { this.unlistenImage_(); } if (this.interimTile) { this.interimTile.dispose(); } this.state = ol.Tile.State.ABORT; this.changed(); ol.Tile.prototype.disposeInternal.call(this); }; /** * Get the image element for this tile. * @inheritDoc * @api */ ol.ImageTile.prototype.getImage = function() { return this.image_; }; /** * @inheritDoc */ ol.ImageTile.prototype.getKey = function() { return this.src_; }; /** * Tracks loading or read errors. * * @private */ ol.ImageTile.prototype.handleImageError_ = function() { this.state = ol.Tile.State.ERROR; this.unlistenImage_(); this.changed(); }; /** * Tracks successful image load. * * @private */ ol.ImageTile.prototype.handleImageLoad_ = function() { if (this.image_.naturalWidth && this.image_.naturalHeight) { this.state = ol.Tile.State.LOADED; } else { this.state = ol.Tile.State.EMPTY; } this.unlistenImage_(); this.changed(); }; /** * Load the image or retry if loading previously failed. * Loading is taken care of by the tile queue, and calling this method is * only needed for preloading or for reloading in case of an error. * @api */ ol.ImageTile.prototype.load = function() { if (this.state == ol.Tile.State.IDLE || this.state == ol.Tile.State.ERROR) { this.state = ol.Tile.State.LOADING; this.changed(); ol.DEBUG && console.assert(!this.imageListenerKeys_, 'this.imageListenerKeys_ should be null'); this.imageListenerKeys_ = [ ol.events.listenOnce(this.image_, ol.events.EventType.ERROR, this.handleImageError_, this), ol.events.listenOnce(this.image_, ol.events.EventType.LOAD, this.handleImageLoad_, this) ]; this.tileLoadFunction_(this, this.src_); } }; /** * Discards event handlers which listen for load completion or errors. * * @private */ ol.ImageTile.prototype.unlistenImage_ = function() { this.imageListenerKeys_.forEach(ol.events.unlistenByKey); this.imageListenerKeys_ = null; };