GWT - How to put Widget B on Widget A - help

I am looking someway to put widgets on each other (each on its layer or something...). Something like the Swing CardLayout but with a transparent background support.

For example

I have

Image img=new Image("imageA.png");
HTML h=new HTML("<img s开发者_运维百科rc=imageB.png>");

How to put "h" on "img" left upper corner?

Any useful comment is appreciated

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You can use AbsolutePanel. It positions it's children at fixed coordinates so you can make them overlap.

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You can either use AbsolutePanel from GWT. Or you can use CSS set z-index of h higher than img and set absolute position from CSS as you want.