java - 单击后保持 mousePressed 处于 Activity 状态

Question

所以我想做的是单击一次后保持 mousePressed 方法“打开”，即使我自己没有按住它。然后再次单击后，它将“关闭”

addMouseListener(new MouseAdapter() {
        public void mousePressed(MouseEvent e) {
            // save coord x,y when mouse is pressed
            oldX = e.getX();
            oldY = e.getY();
        }
    });

    addMouseMotionListener(new MouseMotionAdapter() {
        public void mouseDragged(MouseEvent e) {

            // coord x,y when drag mouse
            currentX = e.getX();
            currentY = e.getY();

            if (g2 != null) {
                // draw oval if g2 context not null
                g2.drawOval(oldX, oldY, width, height);
                g2.fillOval(oldX, oldY, width, height);

                // refresh draw area to repaint
                repaint();

                // store current coords x,y as olds x,y
                oldX = currentX;
                oldY = currentY;
            }
        }
    });

Answer 1

1. 处理mousePressed()事件。然后在您的类中保留一个变量(假设为“clickCounter”)，每次生成事件时都会递增该变量。

2. 然后您需要处理 mouseMoved() 事件以了解鼠标何时移动。

现在，mouseMoved() 事件中的逻辑可以检查变量是否为奇数，这表明鼠标刚刚被单击:

if (clickCounter % 2 == 1)
{
    add your logic here
}

或者您可以保留一个 boolean 变量，每次单击鼠标时都会关闭/打开该变量。