1 files changed, 107 insertions, 0 deletions
diff --git a/frontend/beta/js/YUI-extensions/tree/TreeLoader.js b/frontend/beta/js/YUI-extensions/tree/TreeLoader.js
new file mode 100644
index 0000000..34989bd
--- a/dev/null
+++ b/frontend/beta/js/YUI-extensions/tree/TreeLoader.js
@@ -0,0 +1,107 @@
+YAHOO.ext.tree.TreeLoader = function(config){
+    this.baseParams = {};
+    this.requestMethod = 'POST';
+    YAHOO.ext.util.Config.apply(this, config);
+    
+    this.events = {
+        'beforeload' : true,
+        'load' : true,
+        'loadexception' : true  
+    };
+};
+
+YAHOO.extendX(YAHOO.ext.tree.TreeLoader, YAHOO.ext.util.Observable, {
+    load : function(node, callback){
+        if(node.attributes.children){ // preloaded json children
+            var cs = node.attributes.children;
+            for(var i = 0, len = cs.length; i < len; i++){
+                node.appendChild(this.createNode(cs[i]));
+            }
+            if(typeof callback == 'function'){
+                callback();
+            }
+        }else if(this.dataUrl){
+            this.requestData(node, callback);
+        }
+    },
+    
+    getParams: function(node){
+        var buf = [], bp = this.baseParams;
+        for(var key in bp){
+            if(typeof bp[key] != 'function'){
+                buf.push(encodeURIComponent(key), '=', encodeURIComponent(bp[key]), '&');
+            }
+        }
+        buf.push('node=', encodeURIComponent(node.id));
+        return buf.join('');
+    },
+    
+    requestData : function(node, callback){
+        if(this.fireEvent('beforeload', this, node, callback) !== false){
+            var params = this.getParams(node);
+            var cb = {
+                success: this.handleResponse,
+                failure: this.handleFailure,
+                scope: this,
+        		argument: {callback: callback, node: node}
+            };
+            this.transId = YAHOO.util.Connect.asyncRequest(this.requestMethod, this.dataUrl, cb, params);
+        }else{
+            // if the load is cancelled, make sure we notify 
+            // the node that we are done
+            if(typeof callback == 'function'){
+                callback();
+            }
+        }
+    },
+    
+    isLoading : function(){
+        return this.transId ? true : false;  
+    },
+    
+    abort : function(){
+        if(this.isLoading()){
+            YAHOO.util.Connect.abort(this.transId);
+        }
+    },
+    
+    createNode : function(attr){
+        if(this.applyLoader !== false){
+            attr.loader = this;
+        }
+        return(attr.leaf ? 
+                        new YAHOO.ext.tree.TreeNode(attr) : 
+                        new YAHOO.ext.tree.AsyncTreeNode(attr));  
+    },
+    
+    processResponse : function(response, node, callback){
+        var json = response.responseText;
+        try {
+            var o = eval('('+json+')');
+	        for(var i = 0, len = o.length; i < len; i++){
+	            node.appendChild(this.createNode(o[i])); 
+	        }
+	        if(typeof callback == 'function'){
+                callback();
+            }
+        }catch(e){
+            this.handleFailure(response);
+        }
+    },
+    
+    handleResponse : function(response){
+        this.transId = false;
+        var a = response.argument;
+        this.processResponse(response, a.node, a.callback);
+        this.fireEvent('load', this, a.node, response);
+    },
+    
+    handleFailure : function(response){
+        this.transId = false;
+        var a = response.argument;
+        this.fireEvent('loadexception', this, a.node, response);
+        if(typeof a.callback == 'function'){
+            a.callback();
+        }
+    }
+});