在Java Swing中预装组件？

Question

The .add method appends components to the end of another component. I'm trying to prepend a component to the beginning of another component. How would I accomplish that?

Answer 1

I think you could use the add(Component, int) method, where the int specifies the insertion position. An insertion position of zero should do the trick to prepend a component.

---

(I don't know if this is the right approach though. Maybe a layout manager would be better.)

Answer 2

Component has an add method that takes two params - the object to be added and the index for it to be inserted at. With that in mind, you can attempt to prepend you component by doing the following:

 comp.add(newPanel, 0);
 comp.validate();

Answer 3

You should use a layout manager to accomplish that. The standard layout manager, which is the one with which every container starts by default, just adds items at the end.

Something like this, for example, would do the trick:

JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
panel.add(lowComponent,BorderLayout.CENTER);
panel.add(highComponent,BorderLayout.NORTH);