调整JFrame大小时摆动组件抽搐

Question

I have an undecorated JFrame which has a lot of components inside it (such as JSplitPanes , JPanels with GridBagLayouts, BoxLayouts, BorderLayouts etc). The code of building this JFrame is 2500 lines length, so I wouldn't place it here, or it's simpled version, sorry.

When I drag the JFrame by right or bottom side, it resizes OK, but when I drag it by left or top side, the components inside the JFrame are twitching a lot, so it looks very ugly.

My question is: Why does it happen? How can I prevent it (if I can)? Does anyone fix that in own practice?

UPD: I've written my own resizer for JFrame . It works OK for other windows, which have less amount of components.

Answer 1

Resizing the frame implicitly validates the enclosed Container , which causes doLayout() to be invoked on the affected components each time the size changes. You can see a similar effect in repeated calls to paintComponent() when resizing this AnimationTest . As you observe, using thousands of components scales poorly. As an alternative, leverage the flyweight pattern to render only visible cells, as is done in JTable , JTree , JList , etc. If you can't use one of these, CellRendererPane , seen here , may help.