diff --git a/src/TemplateBinding.js b/src/TemplateBinding.js index cc9cf68..ae69271 100644 --- a/src/TemplateBinding.js +++ b/src/TemplateBinding.js @@ -514,16 +514,7 @@ if (content.firstChild === null) return emptyInstance; - var map = this.bindingMap_; - if (!map || map.content !== content) { - // TODO(rafaelw): Setup a MutationObserver on content to detect - // when the instanceMap is invalid. - map = createInstanceBindingMap(content, - delegate_ && delegate_.prepareBinding) || []; - map.content = content; - this.bindingMap_ = map; - } - + var map = getInstanceBindingMap(content, delegate_); var stagingDocument = getTemplateStagingDocument(this); var instance = stagingDocument.createDocumentFragment(); instance.templateCreator_ = this; @@ -609,7 +600,7 @@ newDelegate_: function(bindingDelegate) { if (!bindingDelegate) - return {}; + return; function delegateFn(name) { var fn = bindingDelegate && bindingDelegate[name]; @@ -622,6 +613,7 @@ } return { + bindingMaps: {}, raw: bindingDelegate, prepareBinding: delegateFn('prepareBinding'), prepareInstanceModel: delegateFn('prepareInstanceModel'), @@ -911,6 +903,43 @@ return map; } + var contentIdCounter = 1; + + // TODO(rafaelw): Setup a MutationObserver on content which clears the id + // so that bindingMaps regenerate when the template.content changes. + function getContentId(content) { + var id = content.id_; + if (!id) + id = content.id_ = contentIdCounter++; + return id; + } + + // Each delegate is associated with a set of bindingMaps, one for each + // content which may be used by a template. The intent is that each binding + // delegate gets the opportunity to prepare* the template content once + // across all uses. + // TODO(rafaelw): Separate out the parse map from the binding map. In the + // current implementation, if two delegates need a binding map for the same + // content, the second will have to reparse. + function getInstanceBindingMap(content, delegate_) { + var contentId = getContentId(content); + if (delegate_) { + var map = delegate_.bindingMaps[contentId]; + if (!map) { + map = delegate_.bindingMaps[contentId] = + createInstanceBindingMap(content, delegate_.prepareBinding) || []; + } + return map; + } + + var map = content.bindingMap_; + if (!map) { + map = content.bindingMap_ = + createInstanceBindingMap(content, undefined) || []; + } + return map; + } + Object.defineProperty(Node.prototype, 'templateInstance', { get: function() { var instance = this.templateInstance_;