From 3791712a10f9cc09af237da25b7ccb8759641b91 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89ric=20Lemoine?= <eric.lemoine@camptocamp.com>
Date: Fri, 8 Aug 2008 12:23:59 +0000
Subject: [PATCH] maxZIndex becomes NULL when the last feature is removed,
 p=pvalsecc, r=me (closes #1670)

git-svn-id: http://svn.openlayers.org/trunk/openlayers@7712 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf
---
 lib/OpenLayers/Renderer/Elements.js | 24 +++++++--
 tests/Renderer/Elements.html        | 76 +++++++++++++++++++++++++++++
 2 files changed, 95 insertions(+), 5 deletions(-)

diff --git a/lib/OpenLayers/Renderer/Elements.js b/lib/OpenLayers/Renderer/Elements.js
index 1113d0bcee..f40120cc2e 100644
--- a/lib/OpenLayers/Renderer/Elements.js
+++ b/lib/OpenLayers/Renderer/Elements.js
@@ -128,24 +128,37 @@ OpenLayers.ElementsIndexer = OpenLayers.Class({
             
             // Reset the maxium z-index based on the last item in the 
             // order array.
-            var lastId = this.order[this.order.length - 1];
-            this.maxZIndex = this.indices[lastId];
+            if (this.order.length > 0) {
+                var lastId = this.order[this.order.length - 1];
+                this.maxZIndex = this.indices[lastId];
+            } else {
+                this.maxZIndex = 0;
+            }
         }
     },
     
+    /**
+     * APIMethod: clear
+     */
+    clear: function() {
+        this.order = [];
+        this.indices = {};
+        this.maxZIndex = 0;
+    },
+    
     /**
      * APIMethod: exists
-     * 
+     *
      * Parameters:
      * node- {DOMElement} The node to test for existence.
-     * 
+     *
      * Returns:
      * {Boolean} Whether or not the node exists in the indexer?
      */
     exists: function(node) {
         return (this.indices[node.id] != null);
     },
-    
+
     /**
      * APIMethod: getZIndex
      * Get the z-index value for the current node from the node data itself.
@@ -395,6 +408,7 @@ OpenLayers.Renderer.Elements = OpenLayers.Class(OpenLayers.Renderer, {
                 this.root.removeChild(this.root.firstChild);
             }
         }
+        this.indexer.clear();
     },
 
     /** 
diff --git a/tests/Renderer/Elements.html b/tests/Renderer/Elements.html
index edd71547b7..a94d4fcca9 100644
--- a/tests/Renderer/Elements.html
+++ b/tests/Renderer/Elements.html
@@ -452,6 +452,82 @@
         OpenLayers.Util.getElement = OpenLayers.Util._getElement;
     }
 
+    function test_Elements_drawAndErase(t) {
+        t.plan(20);
+
+        setUp();
+
+        var r = create_renderer();
+        var element = document.createElement("div");
+        r.root = element;
+        document.body.appendChild(element);
+
+        r.createNode = function(type, id) {
+            var element = document.createElement("div");
+            element.id = id;
+            return element;
+        };
+        r.setStyle = function(node, style, options, geometry) {
+            return node;
+        };
+        
+        var geometry = {
+            id: 'foo',
+            CLASS_NAME: 'bar'
+        };
+        var style = {
+            graphicZIndex: 10
+        };
+        var featureId = 'foo';
+        r.drawGeometry(geometry, style, featureId);
+
+        function count(obj) {
+            var result = 0;
+            for (var i in obj) {
+                result++;
+            }
+            return result;
+        }
+
+        t.ok(r.root.childNodes.length == 1, "root is correctly filled");
+        t.ok(r.indexer.maxZIndex == 10, "indexer.maxZIndex is correctly filled");
+        t.ok(r.indexer.order.length == 1, "indexer.order is correctly filled");
+        t.ok(count(r.indexer.indices) == 1, "indexer.indices is correctly filled");
+
+        r.eraseGeometry(geometry);
+
+        t.ok(r.root.childNodes.length == 0, "root is correctly cleared");
+        t.ok(r.indexer.maxZIndex == 0, "indexer.maxZIndex is correctly reset");
+        t.ok(r.indexer.order.length == 0, "indexer.order is correctly reset");
+        t.ok(count(r.indexer.indices) == 0, "indexer.indices is correctly reset");
+
+        delete(style.graphicZIndex);
+        r.drawGeometry(geometry, style, featureId);
+
+        t.ok(r.root.childNodes.length == 1, "root is correctly filled");
+        t.ok(r.indexer.maxZIndex == 0, "indexer.maxZIndex is correctly filled");
+        t.ok(r.indexer.order.length == 1, "indexer.order is correctly filled");
+        t.ok(count(r.indexer.indices) == 1, "indexer.indices is correctly filled");
+
+        r.clear();
+
+        t.ok(r.root.childNodes.length == 0, "root is correctly cleared");
+        t.ok(r.indexer.maxZIndex == 0, "indexer.maxZIndex is correctly reset");
+        t.ok(r.indexer.order.length == 0, "indexer.order is correctly reset");
+        t.ok(count(r.indexer.indices) == 0, "indexer.indices is correctly reset");
+
+        style.graphicZIndex = 12;
+        r.drawGeometry(geometry, style, featureId);
+
+        t.ok(r.root.childNodes.length == 1, "root is correctly filled");
+        t.ok(r.indexer.maxZIndex == 12, "indexer.maxZIndex is correctly filled");
+        t.ok(r.indexer.order.length == 1, "indexer.order is correctly filled");
+        t.ok(count(r.indexer.indices) == 1, "indexer.indices is correctly filled");
+
+        tearDown();
+    }
+
+
   </script>
 </head>
 <body>