JComboBox选择更改侦听器？ [英] JComboBox Selection Change Listener?

问题描述

每当从 JComboBox 中做出选择时，我都会尝试触发事件。

I'm trying to get an event to fire whenever a choice is made from a JComboBox.

我遇到的问题是没有明显的 addSelectionListener（）方法。

The problem I'm having is that there is no obvious addSelectionListener() method.

我试过使用 actionPerformed（）但它永远不会触发。

I've tried to use actionPerformed() but it never fires.

没有覆盖的模型JComboBox 我没有想法。

如何在上收到有关选择更改的通知JComboBox ？

How do I get notified of a selection change on a JComboBox?

编辑：我不得不道歉，事实证明我使用了一个行为不端的子类 JComboBox ，但我会保留问题，因为你的答案是好的。开始投票。 ：）

I have to apologize it turns out I was using a misbehaving subclass of JComboBox, but I'll leave the question up since your answer is good. Commence the vote down. :)

推荐答案

它应该响应 ActionListeners ，如下所示：

It should respond to ActionListeners, like this:

combo.addActionListener (new ActionListener () {
    public void actionPerformed(ActionEvent e) {
        doSomething();
    }
});

@ John Calsbeek 正确地指出 addItemListener（）也会起作用。但是，您可以获得2 ItemEvents ，一个用于取消选择先前选择的项目，另一个用于选择新项目。只是不要使用这两种事件类型！

@John Calsbeek rightly points out that addItemListener() will work, too. You may get 2 ItemEvents, though, one for the deselection of the previously selected item, and another for the selection of the new item. Just don't use both event types!

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