Performance issue on swing application

Question

Hi,
I have one swing application and i am facing one performance issue after minimizing the applicaton. The same application is taking 2-5 seconds to redraw the screen again when i am trying to maximize it. Is there any way to improve this redraw delay ?..Is there any way to tweak the Event Dispatcher thread and by this we can overcome correct me if i am wrong? .
Is there anybody facing such kind of issue please help me...
Thanks in Advance,
Anish.

Answer 1

Encephalopathic wrote:
good guess. What do you think? Loading the images in the painting methods?That is a common mistake. To the OP, some common errors when overriding paintComponent include:
1. Loading an image each time paintComponent() is called. Just load it once, cache it, and only draw it in paintComponent, this saves you from the IO of loading the image on repaints.
2. Doing application logic/complex operations in paintComponent. paintComponent should be kept fast, only do painting operations, keep long-running tasks, IO, etc. out of it.
3. To a lesser extent, doing lots of complex painting on a repaint call, maybe lots of transforms, translucency, xor-ing, whatever. For most common painting (at least in my work, YMMV), this isn't a problem, but if it is you should consider drawing all "static" stuff to a buffer (such as a BufferedImage) and just painting the BufferedImage, as opposed to drawing all the static stuff each paintComponent call.
The idea is just to keep the painting logic as fast as possible, to avoid slow repaints as you're seeing. Sometimes people don't realize that paintComponent() will be called every time your component needs to be even partially repainted (minimized/maximized window, partially hidden by another window then revealed again, stretched by window resizing, etc.). That's why things like IO are out of the question.
Of course, I'm babbling now. This may not even be your problem, or you may already know all this stuff. If so, just ignore this post!