Re: [repaint()]why necessary ?

From:
Knute Johnson <nospam@rabbitbrush.frazmtn.com>
Newsgroups:
comp.lang.java.help
Date:
Fri, 09 Jul 2010 08:52:54 -0700
Message-ID:
<tBHZn.20375$Ls1.15263@newsfe11.iad>
On 7/9/2010 5:37 AM, dmoyne wrote:

I have a Jpanel on which I have a specifically built :
public void paintComponent(Graphics g) {
...
}

This routine is filling the background of my JPanel in which I install
jscrollpanes ; my jscrollpanes are separated by a vertical space as
specified in the gridlayout attached to the JPanel.

When I remove one by one my jscrollpanes everything works fine until I
reached the last one for which I have to do a repaint () to get the empty
JPanel repainted with paintComponent routine.

Why is this necessary ? All the spaces between my jscrollpanes are correctly
painted by this routine for example when I scroll the JPanel each time a
space is brought into the visible area.

On the other hand if I do not add any jscrollpanes in my panel the empty
space is correctly painted with my routine, so whey after removing the last
jscrollpane the area is not repainted except where the menu rectangle
associated the menu selection to get my scrollpane removed had been ?


Please provide an SSCCE and I'm sure this problem can be diagnosed easily.

--

Knute Johnson
email s/nospam/knute2010/

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