我目前正在尝试修复通过向UPDATE MyTable
SET column = stuff(column,patindex('%[0-9]%',column),0,'9')
添加任意java.awt.event.MouseListener而引入的错误。以下代码是组件的拖放实现的简化版本：
以下是代码：
java.awt.Component现在出于某种原因，如果向拖动的标签添加任意类型的import java.awt.AWTEvent;
import java.awt.Color;
import java.awt.Toolkit;
import java.awt.event.AWTEventListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JWindow;
import javax.swing.SwingUtilities;
public class DragComponentBug {
public static void main(String[] args) {
// set to true to enable the broken behavior
boolean addMouseListener = false;
// set to false to fix the broken behavior by not removing the label from its parent
boolean removeLabel = true;
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocation(100, 100);
JWindow dragWindow = new JWindow();
if (!removeLabel) {
JPanel panel = new JPanel();
panel.setBorder(BorderFactory.createLineBorder(Color.black));
dragWindow.add(panel);
}
JLabel label = new JLabel("Drag me around");
frame.add(label);
MouseAdapter labelListener = new MouseAdapter(){
@Override
public void mousePressed(MouseEvent e) {
System.err.println("mouse pressed: " + e);
}
@Override
public void mouseReleased(MouseEvent e) {
System.err.println("mouse released: " + e);
}
@Override
public void mouseDragged(MouseEvent e) {
System.err.println("mouse dragged: " + e);
}
};
if (addMouseListener) {
label.addMouseListener(labelListener);
label.addMouseMotionListener(labelListener);
}
Toolkit.getDefaultToolkit().addAWTEventListener(new AWTEventListener() {
@Override
public void eventDispatched(AWTEvent event) {
MouseEvent e = (MouseEvent)event;
switch (e.getID()) {
case MouseEvent.MOUSE_PRESSED:
// System.out.println("mouse pressed:" + event);
if (removeLabel) {
label.setBorder(BorderFactory.createLineBorder(Color.black));
dragWindow.add(label);
}
dragWindow.setLocation(e.getLocationOnScreen());
dragWindow.setSize(label.getSize());
dragWindow.setVisible(true);
frame.repaint();
break;
case MouseEvent.MOUSE_RELEASED:
// System.out.println("mouse released:" + event);
if (removeLabel) {
label.setBorder(null);
frame.add(label);
}
frame.repaint();
dragWindow.setVisible(false);
break;
case MouseEvent.MOUSE_DRAGGED:
// System.out.println("mouse dragged:" + event);
dragWindow.setLocation(e.getLocationOnScreen());
break;
default:
break;
}
}
}, AWTEvent.MOUSE_EVENT_MASK | AWTEvent.MOUSE_MOTION_EVENT_MASK);
frame.pack();
frame.setVisible(true);
frame.addWindowListener(new WindowAdapter() {
@Override
public void windowClosed(WindowEvent e) {
dragWindow.dispose();
}
});
}
});
}
}
（或MouseListener），那么拖放行为就会被破坏，全局{{1} }没有接收任何拖动或释放鼠标事件（添加的侦听器也没有）。这可以通过在提供的示例中将MouseMotionListener设置为AWTEventListener来进行测试。
这里的另一个重要方面是，这种行为在某种程度上似乎与事实有关，即在按下鼠标后标签会从其父项中删除。如果没有删除标签，则事件调度将继续有效。在addMouseListener设置为true后，可以通过将removeLabel设置为false来测试此问题。
为什么在将侦听器添加到标签后不再调度鼠标事件，这与从父项中删除标签有何关系？即使将监听器添加到标签中（包括在拖动操作期间删除/添加标签），有没有办法恢复预期的行为？
感谢您的帮助