在cocos2dx的android项目中，怎么让onKeyDown方法执行

首先，进入到引擎目录的cocos\platform\android\java\src\org\cocos2dx\lib，打开Cocos2dxGLSurfaceView.java文件，

找到onKeyDown方法，方法如下：

public boolean onKeyDown(final int pKeyCode, final KeyEvent pKeyEvent) {
        switch (pKeyCode) {
            case KeyEvent.KEYCODE_BACK:

                Cocos2dxVideoHelper.mVideoHandler.sendEmptyMessage(Cocos2dxVideoHelper.KeyEventBack);
            case KeyEvent.KEYCODE_MENU:
            case KeyEvent.KEYCODE_DPAD_LEFT:
            case KeyEvent.KEYCODE_DPAD_RIGHT:
            case KeyEvent.KEYCODE_DPAD_UP:
            case KeyEvent.KEYCODE_DPAD_DOWN:
            case KeyEvent.KEYCODE_ENTER:
            case KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE:
            case KeyEvent.KEYCODE_DPAD_CENTER:
                this.queueEvent(new Runnable() {
                    @Override
                    public void run() {
                        Cocos2dxGLSurfaceView.this.mCocos2dxRenderer.handleKeyDown(pKeyCode);
                    }
                });
                return true;
            default:
                return super.onKeyDown(pKeyCode, pKeyEvent);
        }
    }

修改为：

public boolean onKeyDown(final int pKeyCode, final KeyEvent pKeyEvent) {
        switch (pKeyCode) {
            case KeyEvent.KEYCODE_BACK:
                return false;
                //Cocos2dxVideoHelper.mVideoHandler.sendEmptyMessage(Cocos2dxVideoHelper.KeyEventBack);
            case KeyEvent.KEYCODE_MENU:
            case KeyEvent.KEYCODE_DPAD_LEFT:
            case KeyEvent.KEYCODE_DPAD_RIGHT:
            case KeyEvent.KEYCODE_DPAD_UP:
            case KeyEvent.KEYCODE_DPAD_DOWN:
            case KeyEvent.KEYCODE_ENTER:
            case KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE:
            case KeyEvent.KEYCODE_DPAD_CENTER:
                this.queueEvent(new Runnable() {
                    @Override
                    public void run() {
                        Cocos2dxGLSurfaceView.this.mCocos2dxRenderer.handleKeyDown(pKeyCode);
                    }
                });
                return true;
            default:
                return super.onKeyDown(pKeyCode, pKeyEvent);
        }
    }

然后在主Activity里面重写onKeyDown方法，在游戏中点击返回按钮，就可以进入到重写的onKeyDown方法里面了。