基本上你想用ItemListener你的JComboBox:
JComboBox box = new JComboBox();
// Adds a listener - this performs an action when the item changes.
box.addItemListener(new ItemListener(){
@Override
public void itemStateChanged(ItemEvent e) {
//Checks if this event was caused because an item was selected
if((e.getStateChange() & ItemEvent.SELECTED) == ItemEvent.SELECTED){
System.out.println(e.getItem());
// This is where you'd modify your label based on the dropdown's value - something like this:
label.setText("$900");
}
}});
panel.add(box);
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