問題描述

我想在我的 JFrame 中監聽鼠標移動和點擊.為此，我添加了一個像這樣實現的 MouseListener:(View 類的整個代碼位于 https://gist.github.com/2837224，Board 類在 https://gist.github.com/2837231)

I want to listen for mouse movements and clicks in my JFrame. To do this, I've added a MouseListener implemented like this: (whole code of View class is at https://gist.github.com/2837224, Board class is at https://gist.github.com/2837231)

class BattleshipsFrame extends JFrame {
  private final Board playerBoard, opponentBoard;
  private View view;

/** Main window constructor. */
BattleshipsFrame() {
  ...
  ...   
  ...
  //creating and displaying boards
  playerBoard = new Board();
  opponentBoard = new Board();
  PlayerBoardListener mouseListener = new PlayerBoardListener();
  this.addMouseListener(mouseListener);
  playerBoard.addMouseListener(mouseListener);
  opponentBoard.addMouseListener(new OpponentBoardListener());
  boards.add(playerBoard);
  boards.add(opponentBoard);
  ...
  ...
  ...
}

/** Listener responsible for handling mouse events on player board */
private class PlayerBoardListener extends MouseAdapter {
  @Override public void mousePressed(MouseEvent event) {
    try {
      if(event.getButton() == MouseEvent.BUTTON1 && controllerConnection != null)
        controllerConnection.sendShipPlacedEvent(event.getX()/40, event.getY()/40, ShipType.EMPTY);
    } catch(Exception e) {
      e.printStackTrace();
    }
  }   
  @Override public void mouseMoved(MouseEvent event) {
    //TODO
    System.out.println("Mouse movement detected! Actual mouse position is: " + event.getX()+ "," + event.getY() + ".");
  }   
  @Override public void mouseDragged(MouseEvent event) {
    //TODO
    System.out.println("Mouse movement detected! Actual mouse position is: " + event.getX()+ "," + event.getY() + ".");
  }   

}

有趣的是 mousePressed() 運行良好，但其他兩個卻沒有(移動鼠標時控制臺上沒有顯示).誰能告訴我我做錯了什么?提前致謝！

Funny thing is that mousePressed() is working well, but the other two are not (nothing shows on console while moving the mouse). Anybody could tell me what am I doing wrong? Thanks in advance!

推薦答案

如果要接收 mouseMoved 和 mouseDragged 事件，還需要將監聽器注冊為MouseMotionListener.

If you want to receive mouseMoved and mouseDragged events, you need to also register your listener as a MouseMotionListener.

MouseAdapter adapter = ...
JFrame frame = ...
frame.addMouseListener(adapter);
frame.addMouseMotionListener(adapter);

這篇關于Java - Swing 中的 mouseMoved() 事件處理的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！