Question

如果用户按下JList组件超过3秒，有没有办法捕获事件？

我发现的困难部分是即使在用户松开鼠标左键之前也需要触发事件。（可以通过几个mousePressed和mouseReleased轻松完成）

Answer 1

以下是我用于类似情况的内容：

public class Player implements Runnable, MouseListener
{
    public void mousePressed(MouseEvent e)
    {
        holding = true;
        thread = new Thread(this);
        thread.start();
    }

    public void mouseReleased(MouseEvent e)
    {
        holding = false;
        System.out.println("Held for: "+seconds);
    }
    public void mouseClicked(MouseEvent e){}

    public void run()
    {
        try
        {
            while(holding)
            {
                seconds++;
                // put some code here
                if(seconds==3)
                {
                    holding = false;
                    System.out.println("Held for maximum time!");
                }
            }
        }catch(Exception e){e.printStackTrace();}

    private boolean holding;
    private int seconds;
    private Thread thread;
}

通过调用label.addMouseListener（new Player（））将其添加到JLabel中;

Answer 2

您可以在mouseDown事件侦听器中设置计时器，并在初始延迟3000毫秒后每500毫秒执行一次。在您的鼠标中，您可以取消该计时器。在与TimerTask关联的Timer对象的运行方法上，您可以执行所需任务的计算。这是我的解决方案提案：

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

public class Test
{
    public static void main(String[] args)
    {
        final JFrame f = new JFrame();
        String[] data = {"one", "two", "three", "four"};
        JList myList = new JList(data);
        f.add(myList);
        myList.addMouseListener(
            new MouseAdapter()
            {
                private java.util.Timer t;
                public void mousePressed(MouseEvent e)
                {
                    if(t == null)
                    {
                        t = new java.util.Timer();
                    }
                    t.schedule(new TimerTask()
                    {
                        public void run()
                        {
                            System.out.println("My importan task goes here");
                        }
                    },3000,500);
                }

                public void mouseReleased(MouseEvent e)
                {
                    if(t != null)
                    {
                        t.cancel();
                        t = null;
                    }
                }
            }
            );
            f.pack();
            SwingUtilities.invokeLater(new Runnable()
            {
                public void run()
                {
                    f.setVisible(true);
                }
            }
        );
    }
}

Answer 3

两种不同的解决方案（与之前的解决方案几乎相同）：

    new MouseAdapter() {
        Date pressedTime;
        long timeClicked;

        @Override
        public void mousePressed(MouseEvent e) {
            pressedTime = new Date();
        }
        @Override
        public void mouseReleased(MouseEvent e) {
            timeClicked = new Date().getTime() - pressedTime.getTime();
            if (timeClicked >= 3000) {
                // DO YOUR ACTION HERE
            }
        }
    };

或

new MouseAdapter() {
    boolean mousePressed = false;

    @Override
    public void mousePressed(MouseEvent e) {
        new Thread(new Runnable() {
            @Override
            public void run() {
                mousePressed = true;
                while (mousePressed) {
                    try {
                        Thread.sleep(3000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    if (mousePressed) {
                        // DO YOUR ACTION HERE
                    }
                }
            }
        }).start();
    }

    @Override
    public void mouseReleased(MouseEvent e) {
        mousePressed = false;
    }
}

Answer 4

我有个主意。它不完全是一个倾听者，但你可以做的是mousePressed你可以启动计时器。当计时器达到3秒时，您的事件开始或如果他们放手，在mouseReleased时计时器停止。

Answer 5

使用此代码，您可以检测和管理按下的长或短（如点击），一个事件排除另一个事件。

private int pressStatus = 0; // TO DETECT IF LONG IS REAL LONG OR SHORT PRESSED
private Timer t;

...

@Override
public void mousePressed(final MouseEvent arg0) {
    pressStatus = 0; // to manage simple click or long

    if (t == null) {
        t = new Timer();
    }
    t.schedule(new TimerTask() {
        public void run() {
            pressStatus = 1;

            if (t != null) {
                t.cancel();
                t = null;
            }

            // PRESSED LONG
            int modifiers = arg0.getModifiers();
            if ((modifiers & InputEvent.BUTTON3_MASK) == InputEvent.BUTTON3_MASK) {
                ...
            } else if ((modifiers & InputEvent.BUTTON1_MASK) == InputEvent.BUTTON1_MASK) {
                ....
            }
        }
    }, 700, 1);
}

@Override
public void mouseReleased(MouseEvent arg0) {
    if (t != null) {
        t.cancel();
        t = null;
    }

    // PRESSED SHORT LIKE CLICK
    if (pressStatus == 0) {
        int modifiers = arg0.getModifiers();
        if ((modifiers & InputEvent.BUTTON3_MASK) == InputEvent.BUTTON3_MASK) {
            ...
        } else if ((modifiers & InputEvent.BUTTON1_MASK) == InputEvent.BUTTON1_MASK) {
            ...
        }
    }

    pressStatus = 0;
}

Java检测长按鼠标

5 个答案: