问MoSync - addTo还是addChild？

EN

var myScreen = mosync.nativeui.create("Screen" ,"myScreen", {
               "title": "My Screen"
          });             
          //Create a Button
           var myButton = mosync.nativeui.create("Button" ,"myButton",
           {
              //properties of the button
              "width": "FILL_AVAILABLE_SPACE",
              "text": "Click Me!"
           });


        var myLayout = mosync.nativeui.create("VerticalLayout", "myLayout", 
        {
            "data-width":"FILL_AVAILABLE_SPACE", 
            "data-height":"FILL_AVAILABLE_SPACE"
        });

        myLayout.addTo("myScreen");

        //myButton.addTo("myLayout");
        myLayout.addChild("myButton");