This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
I want to design a JSlider to zoom in or out polygons.What I expected is the old drawing would be replaced the new drawing. Actually I use repaint() method, however I found the screen was mess up. The new and old pictures coexisted when I fired the event.
What is the reason it could be? I am sorry my code is too complex to make it as an example.