java 激活和停用 ComboBox
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/2552520/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
activate and deactivate ComboBox
提问by Jessy
How can I make the comboBox available when the checkBox was uncheck (vice versa)
取消选中复选框时如何使组合框可用（反之亦然）
Why the comboBox is still disable after I unChecked the checkBox?
为什么取消选中复选框后组合框仍处于禁用状态？
choice [] = {"A","B","C"};
JComboBox a = new JComboBox(choice);
JCheckBox chk = new JCheckBox("choice");
...
a.addActionListener(this);
chk.addActionListener(this);
...
public void actionPerformed(ActionEvent e) {
//disable the a comboBox when the checkBox chk was checked
if(e.getSource()==chk)
a.setEnabled(false);
//enable the a comboBox when the checkBox chk was unchecked
else if(e.getSource()!=chk)
a.setEnabled(true);
}
回答by ninesided
If I understand you correctly I think all that you need to do is to change the enabled state of the combo box based on the current value of the checkbox:
如果我理解正确，我认为您需要做的就是根据复选框的当前值更改组合框的启用状态：
public void actionPerformed(ActionEvent e) {
if (e.getSource()==chk) {
a.setEnabled(chk.isSelected());
}
}
回答by Pureferret
I have a similar set up, and I use an Item Listener, like so:
我有一个类似的设置，我使用了一个项目监听器，如下所示：
CheckBox.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
if(e.getStateChange()==ItemEvent.SELECTED){
ComboBox.setEnabled(true);
}else if(e.getStateChange()==ItemEvent.DESELECTED){
ComboBox.setSelectedIndex(-1);
ComboBox.setEnabled(false);
}
}
});
This way the behaviour is different when selected and deselected.
这样，选择和取消选择时的行为是不同的。
回答by Evertvd
if (e.getSource() == chckbxModificar) {
if (chckbxModificar.isSelected()) {
cbxImpuesto.setEnabled(true);
cbxMoneda.setEnabled(true);
txtPorcentaje.setEditable(true);
txtSimbolo.setEditable(true);
} else {
cbxImpuesto.setEnabled(false);
cbxMoneda.setEnabled(false);
txtPorcentaje.setEditable(false);
txtSimbolo.setEditable(false);
}
}
回答by raj
I treid this and worked..
我试过这个并工作了..
public class JF extends JFrame implements ActionListener {
String choice [] = {"A","B","C"};
JComboBox a = new JComboBox(choice);
JCheckBox chk = new JCheckBox("choice");
JF()
{
this.add(a, BorderLayout.NORTH);
this.add(chk, BorderLayout.CENTER);
setDefaultCloseOperation(EXIT_ON_CLOSE);
a.addActionListener(this);
chk.addActionListener(this);
}
public void actionPerformed(ActionEvent e) {
//NOTE THE FOLLOWING LINE!!!!
if(e.getSource()==chk)
a.setEnabled(chk.isSelected());
}
public static void main(String[] args) {
new JF().setVisible(true);
}
}
Your old code didn't work because, even unchecking a checkbox triggers the event. The source of the trigger is the checkbox.. so both while checking and unchecking the event source was chk
您的旧代码不起作用，因为即使取消选中复选框也会触发事件。触发器的来源是复选框..所以在检查和取消选中事件源时都是chk
