Question

我的应用程序中有以下代码。只要按下音量按钮，我就会得到ACTION_DOWN，但是当我释放它时，我希望得到ACTION_UP。这不会发生。为什么？这可能是我的LG G2（Lollipop）上的一个错误吗？我需要的是为VolumeUp按钮操作添加一个监听器。

    @Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_VOLUME_UP) {
        if (event.getAction() == KeyEvent.ACTION_UP) {
            //TODO
            Log.d(TAG,"VOL UP");
            return true;
        }

        if (event.getAction() == KeyEvent.ACTION_DOWN) {
            //TODO
            Log.d(TAG,"VOL DOWN");
            return true;
        }

        Log.d(TAG,String.valueOf(keyCode));

        return true;
    }

    return super.onKeyDown(keyCode, event);
}

Answer 1

这里我编辑两个代码可能是你的工作之一：

代码1：

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_VOLUME_DOWN ||
        keyCode == KeyEvent.KEYCODE_VOLUME_UP) {
        changeColor(keyCode);

        return true;
    }

    return super.onKeyDown(keyCode, event);
}

@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_VOLUME_DOWN ||
        keyCode == KeyEvent.KEYCODE_VOLUME_UP) {
        // do nothing                                                       

        return true;
    }

    return super.onKeyUp(keyCode, event);
}

代码2：

public boolean dispatchKeyEvent(KeyEvent event) {

    if (event.getKeyCode() == KeyEvent.KEYCODE_VOLUME_UP) {             
            return true;
    } else if (event.getKeyCode() == KeyEvent.KEYCODE_VOLUME_DOWN) {
            return true;
    }
    return dispatchKeyEvent(event);
}

Answer 2

您应该尝试捕获所有操作。

public boolean dispatchKeyEvent(KeyEvent event) {
int action = event.getAction();
int keyCode = event.getKeyCode();
    switch (keyCode) {
    case KeyEvent.KEYCODE_VOLUME_UP:
        if (action == KeyEvent.ACTION_DOWN) {
            //TODO
        }
        return true;
    case KeyEvent.KEYCODE_VOLUME_DOWN:
        if (action == KeyEvent.ACTION_DOWN) {
            //TODO
        }
        return true;
    default:
        return super.dispatchKeyEvent(event);
    }
}

发布时，音量调高按钮不提供动作

2 个答案: