Loading dialog doesnt paints while loading other things

I'm trying to do some kind of load screen while a heavy load code its working but i can't make the loading screen gets painted, it just have it's inside in white instread of show it's label of "Loading please wait"

It's seems that the overl开发者_如何学Gooad of the main program doesnt allows the other dialog (launched with a thread to allow me to make it modal but the code go on in background) get painted or something like that

Thank you

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The typical problem is that the code is doing a long running task on the EDT. The solution is "Don't block the EDT".

See the Concurrency in Swing lesson of the Java Tutorials for further details.