java - 在拖动 JSplitPane 分隔线时如何避免(或消耗)鼠标事件？

Question

我有一个打开了连续布局的 JSplitPane。如何在拖动分隔线时阻止其他组件接收鼠标事件？

public class Test {
  public static void main(String[] args) throws Exception {
    JButton top = new JButton("top");
    top.setRolloverEnabled(true);
    top.setMinimumSize(new Dimension(100, 100));
    top.addMouseListener(new MouseAdapter() {
      @Override
      public void mouseEntered(MouseEvent e) {
        top.setBackground(Color.green);
      }

      @Override
      public void mouseExited(MouseEvent e) {
        top.setBackground(null);
      }
    });

    JButton bottom = new JButton("bottom");
    bottom.setRolloverEnabled(true);
    bottom.setMinimumSize(new Dimension(100, 100));
    bottom.addMouseListener(new MouseAdapter() {
      @Override
      public void mouseEntered(MouseEvent e) {
        bottom.setBackground(Color.green);
      }

      @Override
      public void mouseExited(MouseEvent e) {
        bottom.setBackground(null);
      }
    });

    JSplitPane split = new JSplitPane(JSplitPane.VERTICAL_SPLIT);
    split.setResizeWeight(0.5);
    split.setContinuousLayout(true);
    split.setTopComponent(top);
    split.setBottomComponent(bottom);

    JFrame f = new JFrame();
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.setSize(600, 400);
    f.setLocationRelativeTo(null);
    f.getContentPane().setLayout(new BorderLayout());
    f.getContentPane().add(split, BorderLayout.CENTER);
    f.setVisible(true);
  }
}

Answer 1

How do I prevent other components from receiving mouse events while the divider is being dragged?

不知道有什么方法可以关闭所有事件。

但我猜您真正担心的是您不希望背景发生变化。

如果是这样，那么您可以向 MouseListener 添加异常逻辑以在按下鼠标按钮时忽略 mouseEntered 事件:

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

public class Test {
  public static void main(String[] args) throws Exception {
    JButton top = new JButton("top");
    top.setRolloverEnabled(true);
    top.setMinimumSize(new Dimension(100, 100));
    top.addMouseListener(new MouseAdapter() {
      @Override
      public void mouseEntered(MouseEvent e) {
        if (SwingUtilities.isLeftMouseButton(e)) return;

        top.setBackground(Color.green);
      }

      @Override
      public void mouseExited(MouseEvent e) {
        top.setBackground(null);
      }
    });

    JButton bottom = new JButton("bottom");
    bottom.setRolloverEnabled(true);
    bottom.setMinimumSize(new Dimension(100, 100));
    bottom.addMouseListener(new MouseAdapter() {
      @Override
      public void mouseEntered(MouseEvent e) {
        if (SwingUtilities.isLeftMouseButton(e)) return;

        bottom.setBackground(Color.green);
      }

      @Override
      public void mouseExited(MouseEvent e) {
        bottom.setBackground(null);
      }
    });

    JSplitPane split = new JSplitPane(JSplitPane.VERTICAL_SPLIT);
    split.setResizeWeight(0.5);
    split.setContinuousLayout(true);
    split.setTopComponent(top);
    split.setBottomComponent(bottom);

    JFrame f = new JFrame();
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.setSize(600, 400);
    f.setLocationRelativeTo(null);
    f.getContentPane().setLayout(new BorderLayout());
    f.getContentPane().add(split, BorderLayout.CENTER);
    f.setVisible(true);
  }
}

编辑:

也许您可以使用自己的 EventQueue。 EventQueue 负责将事件分派(dispatch)给组件。所以也许你可以:

1. 将 MouseListener 添加到分隔线
2. 在 mousePressed 上，您将默认的 EventQueue 替换为您的自定义 EventQueue，它将忽略除分隔线之外的所有组件的 MouseEvents。
3. 在 mouseRelease 上恢复原始的 EventQueue。

查看 Global Event Dispatching一个帮助您入门的基本示例。