Added $element pseudo-variable that allows accessing the current elem…

…ent (and through it the DOM tree).
studgeek · Oct 3, 2011 · 271d5b8 · 271d5b8
1 parent 0cbcbad
commit 271d5b8
Show file tree

Hide file tree

Showing 3 changed files with 17 additions and 9 deletions.
diff --git a/build/output/knockout-latest.debug.js b/build/output/knockout-latest.debug.js
@@ -2,7 +2,7 @@
 // (c) Steven Sanderson - http://knockoutjs.com/
 // License: MIT (http://www.opensource.org/licenses/mit-license.php)
 
-(function(window,undefined){ 
+(function(window,undefined){
 var ko = window["ko"] = {};
 // Google Closure Compiler helpers (used only to make the minified file smaller)
 ko.exportSymbol = function(publicPath, object) {
@@ -1582,7 +1582,7 @@ ko.exportSymbol('ko.jsonExpressionRewriting.insertPropertyAccessorsIntoJson', ko
 
         'getBindings': function(node, bindingContext) {
             var bindingsString = this['getBindingsString'](node, bindingContext);
-            return bindingsString ? this['parseBindingsString'](bindingsString, bindingContext) : null;
+            return bindingsString ? this['parseBindingsString'](bindingsString, bindingContext, node) : null;
         },
 
         // The following function is only used internally by this default provider.
@@ -1597,11 +1597,12 @@ ko.exportSymbol('ko.jsonExpressionRewriting.insertPropertyAccessorsIntoJson', ko
 
         // The following function is only used internally by this default provider.
         // It's not part of the interface definition for a general binding provider.
-        'parseBindingsString': function(bindingsString, bindingContext) {
+        'parseBindingsString': function(bindingsString, bindingContext, node) {
             try {
                 var viewModel = bindingContext['$data'];
                 var rewrittenBindings = " { " + ko.jsonExpressionRewriting.insertPropertyAccessorsIntoJson(bindingsString) + " } ";
-                return ko.utils.evalWithinScope(rewrittenBindings, viewModel === null ? window : viewModel, bindingContext);
+				return ko.utils.evalWithinScope(rewrittenBindings, viewModel === null ? window : viewModel,
+					bindingContext, { "$element" : node });
             } catch (ex) {
                 throw new Error("Unable to parse bindings.\nMessage: " + ex + ";\nBindings value: " + bindingsString);
             }           
@@ -3051,4 +3052,4 @@ ko.exportSymbol('ko.nativeTemplateEngine', ko.nativeTemplateEngine);(function()
         ko.setTemplateEngine(jqueryTmplTemplateEngineInstance);
 
     ko.exportSymbol('ko.jqueryTmplTemplateEngine', ko.jqueryTmplTemplateEngine);
-})();})(window);                  
+})();})(window);
diff --git a/spec/bindingAttributeBehaviors.js b/spec/bindingAttributeBehaviors.js
@@ -159,7 +159,13 @@ describe('Binding attribute syntax', {
         value_of(passedValues[1]).should_be("goodbye");
     },
 
-    'Should be able to refer to the bound object itself (at the root scope, the viewmodel) via $data': function() {
+    'Should be able to use $element in binding value': function() {
+        testNode.innerHTML = "<div data-bind='text: $element.tagName'></div>";
+        ko.applyBindings({}, testNode);
+        value_of(testNode).should_contain_text("DIV");
+    },
+
+	    'Should be able to refer to the bound object itself (at the root scope, the viewmodel) via $data': function() {
         testNode.innerHTML = "<div data-bind='text: $data.someProp'></div>";
         ko.applyBindings({ someProp: 'My prop value' }, testNode);
         value_of(testNode).should_contain_text("My prop value");

diff --git a/src/binding/bindingProvider.js b/src/binding/bindingProvider.js
@@ -14,7 +14,7 @@
 
         'getBindings': function(node, bindingContext) {
             var bindingsString = this['getBindingsString'](node, bindingContext);
-            return bindingsString ? this['parseBindingsString'](bindingsString, bindingContext) : null;
+            return bindingsString ? this['parseBindingsString'](bindingsString, bindingContext, node) : null;
         },
 
         // The following function is only used internally by this default provider.
@@ -29,11 +29,12 @@
 
         // The following function is only used internally by this default provider.
         // It's not part of the interface definition for a general binding provider.
-        'parseBindingsString': function(bindingsString, bindingContext) {
+        'parseBindingsString': function(bindingsString, bindingContext, node) {
             try {
                 var viewModel = bindingContext['$data'];
                 var rewrittenBindings = " { " + ko.jsonExpressionRewriting.insertPropertyAccessorsIntoJson(bindingsString) + " } ";
-                return ko.utils.evalWithinScope(rewrittenBindings, viewModel === null ? window : viewModel, bindingContext);
+				return ko.utils.evalWithinScope(rewrittenBindings, viewModel === null ? window : viewModel,
+					bindingContext, { "$element" : node });
             } catch (ex) {
                 throw new Error("Unable to parse bindings.\nMessage: " + ex + ";\nBindings value: " + bindingsString);
             }