From 0e8e7ab620ec81e0909f04e0a03025090b347ff8 Mon Sep 17 00:00:00 2001 From: euzuro Date: Wed, 12 Sep 2007 04:00:31 +0000 Subject: [PATCH] making the layerswitcher a little smarter. Instead of fancy 'noEvent' parameters, we just keep track of the state at each redraw. When asked to redraw, we then check first to see if anything has changed before going ahead with the redraw. Also in this patch, we add a 'visibilitychanged' event to the layer's events object -- upon request by users. (Closes #878) git-svn-id: http://svn.openlayers.org/trunk/openlayers@4229 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf --- lib/OpenLayers/Control/LayerSwitcher.js | 58 +++++++++++++++++++++++-- lib/OpenLayers/Layer.js | 9 ++-- lib/OpenLayers/Map.js | 9 ++-- tests/Control/test_LayerSwitcher.html | 12 ++++- tests/test_Layer.html | 6 ++- 5 files changed, 78 insertions(+), 16 deletions(-) diff --git a/lib/OpenLayers/Control/LayerSwitcher.js b/lib/OpenLayers/Control/LayerSwitcher.js index 5a25fa72d9..479f60d306 100644 --- a/lib/OpenLayers/Control/LayerSwitcher.js +++ b/lib/OpenLayers/Control/LayerSwitcher.js @@ -19,6 +19,14 @@ OpenLayers.Control.LayerSwitcher = */ activeColor: "darkblue", + /** + * Property: layerStates + * {Array(Object)} Basically a copy of the "state" of the map's layers + * the last time the control was drawn. We have this in order to avoid + * unnecessarily redrawing the control. + */ + layerStates: null, + // DOM Elements @@ -86,6 +94,7 @@ OpenLayers.Control.LayerSwitcher = */ initialize: function(options) { OpenLayers.Control.prototype.initialize.apply(this, arguments); + this.layerStates = []; }, /** @@ -171,6 +180,32 @@ OpenLayers.Control.LayerSwitcher = }, + /** + * Method: checkRedraw + * Checks if the layer state has changed since the last redraw() call. + * + * Returns: + * {Boolean} The layer state changed since the last redraw() call. + */ + checkRedraw: function() { + var redraw = false; + if ( !this.layerStates.length || + (this.map.layers.length != this.layerStates.length) ) { + redraw = true; + } else { + for (var i=0; i < this.layerStates.length; i++) { + var layerState = this.layerStates[i]; + var layer = this.map.layers[i]; + if ( (layerState.name != layer.name) || + (layerState.visibility != layer.visibility) ) { + redraw = true; + break; + } + } + } + return redraw; + }, + /** * Method: redraw * Goes through and takes the current state of the Map and rebuilds the @@ -181,6 +216,11 @@ OpenLayers.Control.LayerSwitcher = * {DOMElement} A reference to the DIV DOMElement containing the control */ redraw: function() { + //if the state hasn't changed since last redraw, no need + // to do anything. Just return the existing div. + if (!this.checkRedraw()) { + return this.div; + } //clear out previous layers this.clearLayersArray("base"); @@ -189,6 +229,19 @@ OpenLayers.Control.LayerSwitcher = var containsOverlays = false; var containsBaseLayers = false; + // Save state -- for checking layer if the map state changed. + // We save this before redrawing, because in the process of redrawing + // we will trigger more visibility changes, and we want to not redraw + // and enter an infinite loop. + this.layerStates = new Array(this.map.layers.length); + for (var i = 0; i < this.map.layers.length; i++) { + var layer = this.map.layers[i]; + this.layerStates[i] = { + 'name': layer.name, + 'visibility': layer.visibility + }; + } + var layers = this.map.layers.slice(); if (!this.ascending) { layers.reverse(); } for( var i = 0; i < layers.length; i++) { @@ -286,8 +339,7 @@ OpenLayers.Control.LayerSwitcher = if (!this.inputElem.disabled) { if (this.inputElem.type == "radio") { this.inputElem.checked = true; - this.layer.map.setBaseLayer(this.layer, true); - this.layer.map.events.triggerEvent("changebaselayer"); + this.layer.map.setBaseLayer(this.layer); } else { this.inputElem.checked = !this.inputElem.checked; this.layerSwitcher.updateMap(); @@ -329,7 +381,7 @@ OpenLayers.Control.LayerSwitcher = // set the correct visibilities for the overlays for(var i=0; i < this.dataLayers.length; i++) { var layerEntry = this.dataLayers[i]; - layerEntry.layer.setVisibility(layerEntry.inputElem.checked, true); + layerEntry.layer.setVisibility(layerEntry.inputElem.checked); } }, diff --git a/lib/OpenLayers/Layer.js b/lib/OpenLayers/Layer.js index 9534dee644..c5cec481e9 100644 --- a/lib/OpenLayers/Layer.js +++ b/lib/OpenLayers/Layer.js @@ -32,7 +32,7 @@ OpenLayers.Layer = OpenLayers.Class({ * Constant: EVENT_TYPES * {Array(String)} Supported application event types */ - EVENT_TYPES: [ "loadstart", "loadend", "loadcancel"], + EVENT_TYPES: [ "loadstart", "loadend", "loadcancel", "visibilitychanged"], /** * APIProperty: events`` @@ -497,17 +497,16 @@ OpenLayers.Layer = OpenLayers.Class({ * * Parameters: * visible - {Boolean} Whether or not to display the layer (if in range) - * noEvent - {Boolean} */ - setVisibility: function(visibility, noEvent) { + setVisibility: function(visibility) { if (visibility != this.visibility) { this.visibility = visibility; this.display(visibility); this.redraw(); - if ((this.map != null) && - ((noEvent == null) || (noEvent == false))) { + if (this.map != null) { this.map.events.triggerEvent("changelayer"); } + this.events.triggerEvent("visibilitychanged"); } }, diff --git a/lib/OpenLayers/Map.js b/lib/OpenLayers/Map.js index d612577d06..75b731de95 100644 --- a/lib/OpenLayers/Map.js +++ b/lib/OpenLayers/Map.js @@ -660,9 +660,8 @@ OpenLayers.Map = OpenLayers.Class({ * * Parameters: * newBaseLayer - {} - * noEvent - {Boolean} */ - setBaseLayer: function(newBaseLayer, noEvent) { + setBaseLayer: function(newBaseLayer) { var oldExtent = null; if(this.baseLayer) { oldExtent = this.baseLayer.getExtent(); @@ -675,7 +674,7 @@ OpenLayers.Map = OpenLayers.Class({ // make the old base layer invisible if (this.baseLayer != null) { - this.baseLayer.setVisibility(false, noEvent); + this.baseLayer.setVisibility(false); } // set new baselayer and make it visible @@ -701,9 +700,7 @@ OpenLayers.Map = OpenLayers.Class({ } } - if ((noEvent == null) || (noEvent == false)) { - this.events.triggerEvent("changebaselayer"); - } + this.events.triggerEvent("changebaselayer"); } } }, diff --git a/tests/Control/test_LayerSwitcher.html b/tests/Control/test_LayerSwitcher.html index 7f203cd752..625913e6cc 100644 --- a/tests/Control/test_LayerSwitcher.html +++ b/tests/Control/test_LayerSwitcher.html @@ -65,7 +65,7 @@ function test_04_Control_LayerSwitcher_redraw (t) { - t.plan( 8 ); + t.plan( 12 ); map = new OpenLayers.Map('map'); var layer = new OpenLayers.Layer.WMS("WMS", @@ -92,6 +92,16 @@ t.eq(markersInput.name, markers.name, "wms correctly named"); t.eq(markersInput.value, markers.name, "wms correctly valued"); + t.eq(false, control.checkRedraw(), "check redraw is false"); + + control = new OpenLayers.Control.LayerSwitcher(); + control.redraw = function() { + t.ok(true, "redraw called when setting vis"); + } + map.addControl(control); + markers.setVisibility(false); + t.eq(control.checkRedraw(), true, "check redraw is true after changing layer and not letting redraw happen."); + } function test_05_Control_LayerSwitcher_ascendingw (t) { diff --git a/tests/test_Layer.html b/tests/test_Layer.html index 578d01e983..a88eb9970a 100644 --- a/tests/test_Layer.html +++ b/tests/test_Layer.html @@ -118,7 +118,7 @@ function test_05_Layer_visibility(t) { - t.plan(5) + t.plan(7); var layer = new OpenLayers.Layer('Test Layer'); @@ -140,6 +140,10 @@ layermoved = false; layer.moveTo = function() { layermoved = true; } + layer.events.register('visibilitychanged', t, function() { + this.ok(true, "Visibility changed calls layer event."); + }); + layer.setVisibility(false); t.eq(layermoved, false, "Layer didn't move when calling setvis false");