Java 如何向动作侦听器提供变量?

Java 如何向动作侦听器提供变量?,java,variables,visibility,actionlistener,Java,Variables,Visibility,Actionlistener,我在类中有一个静态变量partner。我想在按下单选按钮时设置这些变量的值。这是我尝试使用的代码: for (String playerName: players) { option = new JRadioButton(playerName, false); option.addActionListener(new ActionListener(){ @Override public void actionPerformed(ActionEven

我在类中有一个静态变量
partner
。我想在按下单选按钮时设置这些变量的值。这是我尝试使用的代码:

for (String playerName: players) {
    option = new JRadioButton(playerName, false);
    option.addActionListener(new ActionListener(){
        @Override
        public void actionPerformed(ActionEvent evt) {
            partner = playerName;
        }
    });
    partnerSelectionPanel.add(option);
    group.add(option);
}

这里的问题是
actionPerformed
没有看到在循环中创建的变量
playerName
。如何将此变量传递给actionListener?

变量必须是final才能将其传递给内部类

for (final String playerName: players) {
    option = new JRadioButton(playerName, false);
    option.addActionListener(new ActionListener(){
        @Override
        public void actionPerformed(ActionEvent evt) {
            partner = playerName;
        }
    });
    partnerSelectionPanel.add(option);
    group.add(option);
}
传递给内部类的局部变量必须是final。最初我认为您不能在for循环中使
playerName
成为final,但事实上您可以。如果不是这样,您只需将
playerName
存储在附加的final变量(
final String pn=playerName
)中,并使用
pn
from
actionPerformed

JButton button = new JButton("test");

button.addActionListiner(new ActionForButton("test1","test2"));

class ActionForButton implements ActionListener {

    String arg,arg2;
    ActionFroButton(String a,String b) {
        arg = a; arg2 = b;
    }

        @Override
        public void actionPerformed(ActionEvent e) {
            Sustem.out.println(arg + "--" + arg2);
        }
}