Sorry, you don't give enough information though.
When you said that ToastMessageShow(Label1.Text,False) and I see the toast message, but nothing in the label, I thought that the text was changed but not appearing in the Label.
Is the name of the Label really Label1 ?
You should post a small project showing the problem otherwise we must try to guess what you could have done wrong.
I SOLVED!
I was depressed because I created a new project and didn't have the same problem.
But the problem is this: I created (in the original project) a new TabHost and this call the same layouts.
The first tabhost cover the second and the text is displayed on the second.