问题
When using null layout, how to resize components?
I mean their position and size. I know that using layout managers we need not take care of this issue. But my requirement is to move components in the panel. So I ought to use null layout.
Please let me know if you have ideas regarding finding new locations to place components on resize of the frame.
回答1:
Doing Without a Layout Manager tutorial may help, although it is recommended that you use a layout manager, if at all possible.
Recommendations
- Either use a layout manager, or
- Register a ComponentListener and manually resize/position components when a resize event occurs.
The labor incurred with the latter approach may be enormous, and hence why using a layout manager comes highly recommended. Another, albeit cheap alternative (which I'm sure violates your requirements), is to invoke setResizable(false) on your JFrame.
回答2:
for a component to be displayed in a null layout, they must of the bounds set on the component. They need a position(x,y) and a width/height
来源：https://stackoverflow.com/questions/6459001/resizing-a-frame-and-its-components-when-using-null-layout