Three Composites in an inheritance hierarchy, there looks like that can use GWT Designer to design the UI.
But when i copy the code to my project and click the "Design" button of MyC2.java,
I get an error window which message is:
Designer was unable to find any GUI elements in your source.
Check that the open compilation unit is a GUI class.
My designer version is GWTDesigner_v4.0.0_win32_x86.exe
Please help me.