Question

我创建了一个GUI，每次按一个键都会打印出一个列表。或者我认为......但是不是运行我在按键上做的功能，而是GUI一直都是这样做的。

这是我的代码：

package main;

import java.util.ArrayList;
import javax.swing.*;
import java.awt.*;

public class Elements{
    static ArrayList<String> composition = new ArrayList<String>();
    static Boolean x = true;
    static JLabel gLabel = GUI();
    public static void main(String[] args){
        while(x == true){
            gLabel.getInputMap(JComponent.WHEN_FOCUSED).put(KeyStroke.getKeyStroke("Q"), "water");
            gLabel.getActionMap().put("water", water());
            gLabel.getInputMap(JComponent.WHEN_FOCUSED).put(KeyStroke.getKeyStroke("W"), "life");
            gLabel.getActionMap().put("life", life());
        }
    }
    public static Action water(){
        if(composition.contains("Fire")){
            composition.remove("Fire");
            composition.add("Steam");
        } else if(composition.contains("Cold")){
            composition.remove("Cold");
            composition.add("Ice");
        } else if(composition.contains("Arcane")){
            composition.remove("Arcane");
            composition.add("Poison");
        } else if(composition.contains("Lightning")){
            composition.remove("Lightning");
        } else {
            composition.add("Water");
        }
        int y = 0;
        while(y < 100){
            System.out.println("");
            y++;
        }
        System.out.println(composition);
        x = true;
        return null;
    }
    public static Action life(){
        if(composition.contains("Arcane")){
            composition.remove("Arcane");
        } else {
            composition.add("Life");
        }
        int y = 0;
        while(y < 100){
            System.out.println("");
            y++;
        }
        System.out.println(composition);
        x = true;
        return null;
    }
    private static JLabel GUI(){
        JFrame frame = new JFrame("KeyPress Handler");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JLabel label = new JLabel("This window listens for key presses and does stuff with them. Isn't that cool?");
        label.setPreferredSize(new Dimension(175, 100));
        frame.getContentPane().add(label, BorderLayout.CENTER);

        frame.pack();
        frame.setVisible(true);
        return label;
    }
}

不是在按键上运行life()和water()，而是一直运行。

我得到了

的输出

[Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life, Water, Life]

没有触及任何事情！

我不知道为什么会这样，但我认为这与以下情况有关： gLabel.getInputMap(JComponent.WHEN_FOCUSED).put(KeyStroke.getKeyStroke("Q"), "water");

和：

gLabel.getInputMap(JComponent.WHEN_FOCUSED).put(KeyStroke.getKeyStroke("W"), "life");

如果有人能告诉我问题是什么以及如何解决问题，那就太棒了。

谢谢，海伦

P.S。：我添加了2个新行： gLabel.getInputMap(JComponent.WHEN_FOCUSED).put(KeyStroke.getKeyStroke("Enter"), "stop"); gLabel.getActionMap().put("stop", stop());

函数stop()如下：

public static Action stop(){ x = false; return null;

据我了解，这是为了添加stop()到Space的新键绑定。

此外，进行这些更改后，输出减少到[Water, Life]。

（另外，修复了while循环）

Answer 1

while(x = true){ - ＆gt;不知何故，你必须在while条件中设置x布尔变量false。你的while循环中没有别的东西。

Answer 2

while ( x = true )必须更改为while ( x == true )

并且您必须在代码中（在x是静态变量的情况下，尤其是在您的主要代码中）将x的值更改为false。

那就是说，我不确定你想要实现什么，我认为你的方向是错误的。

如何阻止我的GUI无限期地打印文本？ - Java

2 个答案: