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confusing awt question

 
Greenhorn
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An AWT GUI under exposure condition,which one or more method will be invok when it redraw?

A.paint();
B.update();
C.repaint();
D.drawing();
Ans = c
well , I think its paint(), could someone plz provide explanation regarding it. thanks in advance
 
mister krabs
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paint() is never invoked directly. repaint() triggers an update() and a paint() which is what is needed to redraw the screen.
 
Gaurav Goyal
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Hi Thomas Paul
the question says " method which is invoked" , that means user is not invoking it , the method is invoked by the jvm. and I think jvm always call paint() rather than repaint(). repaint() is generally used in user codes
what do u say

 
Thomas Paul
mister krabs
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The update() method clears the screen so paint() can never just be called by itself. The paint() method assumes the screen has already been cleared. repaint() is always called.
 
Thomas Paul
mister krabs
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Also paint() requires that a graphics object be passed in while repaint() doesn't. repaint() actually calculates the graphics area and invokes the peer for the component being repainted.
 
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