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update and repaint

Rich Wright

Joined: Oct 08, 1999
Posts: 17
I'm a little confused about update() and repaint(). If you need to refresh part of the screen that was hidden by another window would you call the repaint() method (The repaint() method would schedule a call to the update() method).
Thanks for your help
Pawel Veselov
Ranch Hand

Joined: Jan 14, 1999
Posts: 165
You are correct.
The difference between update() and repaint() is that update has Graphics instance as an argument, so it does know where to draw on.
repaint() is a empty scheduler, that doesn't make a repaint. This allow you to call repaint() and continue execution. The update() will be called in another thread (AWT-Motif, if I am not mistaken)
To repaint piece of a component, you can use repaint(int, int, int, int). In that case, update() will received clipped Graphics.

With best of best regards, Pawel S. Veselov ( aka Black Angel )

With best of best regards, Pawel S. Veselov ( aka Black Angel )
I agree. Here's the link:
subject: update and repaint
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