| /* Copyright (c) 2006-2010 by OpenLayers Contributors (see authors.txt for | |
| * full list of contributors). Published under the Clear BSD license. | |
| * See http://svn.openlayers.org/trunk/openlayers/license.txt for the | |
| * full text of the license. */ | |
| /** | |
| * @requires OpenLayers/Strategy.js | |
| */ | |
| /** | |
| * Class: OpenLayers.Strategy.Refresh | |
| * A strategy that refreshes the layer. By default the strategy waits for a | |
| * call to <refresh> before refreshing. By configuring the strategy with | |
| * the <interval> option, refreshing can take place automatically. | |
| * | |
| * Inherits from: | |
| * - <OpenLayers.Strategy> | |
| */ | |
| OpenLayers.Strategy.Refresh = OpenLayers.Class(OpenLayers.Strategy, { | |
| /** | |
| * Property: force | |
| * {Boolean} Force a refresh on the layer. Default is false. | |
| */ | |
| force: false, | |
| /** | |
| * Property: interval | |
| * {Number} Auto-refresh. Default is 0. If > 0, layer will be refreshed | |
| * every N milliseconds. | |
| */ | |
| interval: 0, | |
| /** | |
| * Property: timer | |
| * {Number} The id of the timer. | |
| */ | |
| timer: null, | |
| /** | |
| * Constructor: OpenLayers.Strategy.Refresh | |
| * Create a new Refresh strategy. | |
| * | |
| * Parameters: | |
| * options - {Object} Optional object whose properties will be set on the | |
| * instance. | |
| */ | |
| initialize: function(options) { | |
| OpenLayers.Strategy.prototype.initialize.apply(this, [options]); | |
| }, | |
| /** | |
| * APIMethod: activate | |
| * Activate the strategy. Register any listeners, do appropriate setup. | |
| * | |
| * Returns: | |
| * {Boolean} True if the strategy was successfully activated. | |
| */ | |
| activate: function() { | |
| var activated = OpenLayers.Strategy.prototype.activate.call(this); | |
| if(activated) { | |
| if(this.layer.visibility === true) { | |
| this.start(); | |
| } | |
| this.layer.events.on({ | |
| "visibilitychanged": this.reset, | |
| scope: this | |
| }); | |
| } | |
| return activated; | |
| }, | |
| /** | |
| * APIMethod: deactivate | |
| * Deactivate the strategy. Unregister any listeners, do appropriate | |
| * tear-down. | |
| * | |
| * Returns: | |
| * {Boolean} True if the strategy was successfully deactivated. | |
| */ | |
| deactivate: function() { | |
| var deactivated = OpenLayers.Strategy.prototype.deactivate.call(this); | |
| if(deactivated) { | |
| this.stop(); | |
| } | |
| return deactivated; | |
| }, | |
| /** | |
| * Method: reset | |
| * Start or cancel the refresh interval depending on the visibility of | |
| * the layer. | |
| */ | |
| reset: function() { | |
| if(this.layer.visibility === true) { | |
| this.start(); | |
| } else { | |
| this.stop(); | |
| } | |
| }, | |
| /** | |
| * Method: start | |
| * Start the refresh interval. | |
| */ | |
| start: function() { | |
| if(this.interval && typeof this.interval === "number" && | |
| this.interval > 0) { | |
| this.timer = window.setInterval( | |
| OpenLayers.Function.bind(this.refresh, this), | |
| this.interval); | |
| } | |
| }, | |
| /** | |
| * APIMethod: refresh | |
| * Tell the strategy to refresh which will refresh the layer. | |
| */ | |
| refresh: function() { | |
| if (this.layer && this.layer.refresh && | |
| typeof this.layer.refresh == "function") { | |
| this.layer.refresh({force: this.force}); | |
| } | |
| }, | |
| /** | |
| * Method: stop | |
| * Cancels the refresh interval. | |
| */ | |
| stop: function() { | |
| if(this.timer !== null) { | |
| window.clearInterval(this.timer); | |
| this.timer = null; | |
| } | |
| }, | |
| CLASS_NAME: "OpenLayers.Strategy.Refresh" | |
| }); | |