I solved it. the timertask DO change the text, but I must also call text.refreshDrawableState(); to make the change visible. But is this the best way of solving it?
EDIT: refreshDrawableState solved it for TextViews... however, now I have some problems with showing Toasts.
EDIT2: I was mistaking. I have not solved it... refreshDrawableState does not work.
EDIT3: The program even hangs without error messages when I try to toast...