openui5 getBinding（）返回未定义

Question

I am trying to listen to an event that indicates a custom control's aggregation binding has changed.

My goal is to locate the binding object associated with the aggregation and attach a handler to it.

I understand that binding occurs within onBeforeRendering, so I added an onAfterRendering function which is called successfully

However this.getBinding("_myAggregation") is still undefined, so that I cannot attach any event handler. The outline of the code is as follows:

 sap.ui.core.Control.extend("myControl", { metadata : { properties : { ... }, aggregations : { _myAggregation : { type : "myInnerControl", multiple : false } }, events : { ... } }, init : function() { var self = this; self.setAggregation("_myAggregation", new myInnerControl.bindElement("queryModel>")); }, onAfterRendering : function(oEvent) { if (sap.ui.core.Control.prototype.onAfterRendering) { sap.ui.core.Control.prototype.onAfterRendering.apply(this, arguments); } this.getBinding("_myAggregation").attachChange(function() { alert("model change"); }); }, renderer : function(oRm, oControl) { ... } }); 

I am using openui5 version 1.28.15 The application works otherwise: correctly renders the information in the JSONModel, handles edits etc.

Answer 1

Hope this might help you.

http://jsbin.com/qagani/edit?html,js,output

The binding is more related to Managed Object rather than control itself.