Ticket #878: 878.2.patch

tests/test_Layer.html

@@ -118 +118 @@
-
-    function test_05_Layer_visibility(t) {
-
-5)
+7);
-
-        var layer = new OpenLayers.Layer('Test Layer');
-    
@@ -140 +140 @@
-        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");
-        

tests/Control/test_LayerSwitcher.html

@@ -65 +65 @@
-
-    function test_04_Control_LayerSwitcher_redraw (t) {
-
-8
+12
-
-        map = new OpenLayers.Map('map');
-        var layer = new OpenLayers.Layer.WMS("WMS", 
@@ -92 +92 @@
-        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) {
-

lib/OpenLayers/Control/LayerSwitcher.js

@@ -19 +19 @@
-     */
-    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 +94 @@
-     */
-    initialize: function(options) {
-        OpenLayers.Control.prototype.initialize.apply(this, arguments);
+        this.layerStates = [];
-    },
-
-    /**
@@ -171 +180 @@
-    },
-
-
+    /**
+     * 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 +216 @@
-     * {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 +229 @@
-        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 +339 @@
-        if (!this.inputElem.disabled) {
-            if (this.inputElem.type == "radio") {
-                this.inputElem.checked = true;
-
-
+
-            } else {
-                this.inputElem.checked = !this.inputElem.checked;
-                this.layerSwitcher.updateMap();
@@ -329 +381 @@
-        // set the correct visibilities for the overlays
-        for(var i=0; i < this.dataLayers.length; i++) {
-            var layerEntry = this.dataLayers[i];   
-, true
+
-        }
-
-    },

lib/OpenLayers/Layer.js

@@ -32 +32 @@
-     * Constant: EVENT_TYPES
-     * {Array(String)} Supported application event types
-     */
-
+, "visibilitychanged"
-        
-    /**
-     * APIProperty: events``
@@ -497 +497 @@
-     * 
-     * Parameters:
-     * visible - {Boolean} Whether or not to display the layer (if in range)
-     * noEvent - {Boolean}
-     */
-, noEvent
+
-        if (visibility != this.visibility) {
-            this.visibility = visibility;
-            this.display(visibility);
-            this.redraw();
-
-
+
-                this.map.events.triggerEvent("changelayer");
-            }
+            this.events.triggerEvent("visibilitychanged");
-        }
-    },
-

lib/OpenLayers/Map.js

@@ -660 +660 @@
-     * 
-     * Parameters:
-     * newBaseLayer - {<OpenLayers.Layer>}
-     * noEvent - {Boolean}
-     */
-, noEvent
+
-        var oldExtent = null;
-        if(this.baseLayer) {
-            oldExtent = this.baseLayer.getExtent();
@@ -675 +674 @@
-
-                // make the old base layer invisible 
-                if (this.baseLayer != null) {
-, noEvent
+
-                }
-
-                // set new baselayer and make it visible
@@ -701 +700 @@
-                    }
-                }
-
-
-
-
+
-            }        
-        }
-    },