1

我正在 android studio 中创建一个钢琴应用程序:

应用截图

我的播放按钮有一个点击监听器,当按下它时应该使录制和播放按钮不可见,而在播放录制的声音时停止按钮可见。

播放按钮

mBtn_Play.setOnClickListener(new View.OnClickListener()
    {
        @Override
        public void onClick(View v)
        {
            mRecordingState = "Playing";
            switchButtonVisibility();

            for (final int sound: mListRecordedSounds )
            {
                if (mRecordingState == "Ready")
                {//break out of loop when stop button is pressed
                    break;
                }
                else {

                    mSoundPool.play(sound, 1,1,1,0,1);
                    try
                    {
                        Thread.sleep(500);
                    }
                    catch (InterruptedException e)
                    {
                        e.printStackTrace();
                    }
                }
            }
        }
    });
}

切换按钮可见性的方法

private void switchButtonVisibility()
{

    if (mRecordingState != "Ready")
    {
        mBtn_Stop.setVisibility(View.VISIBLE);
        mBtn_Record.setVisibility(View.GONE);
        mBtn_Play.setVisibility(View.GONE);

    }
    else
    {
        mBtn_Stop.setVisibility(View.GONE);
        mBtn_Record.setVisibility(View.VISIBLE);
        mBtn_Play.setVisibility(View.VISIBLE);
    }

}

使用记录和停止按钮,这可以正常工作

mBtn_Record.setOnClickListener(new View.OnClickListener()
    {
        @Override
        public void onClick(View v)
        {
            mListRecordedSounds.clear();
            mRecordingState = "Recording";
            switchButtonVisibility();

        }
    });
mBtn_Stop.setOnClickListener(new View.OnClickListener()
    {
        @Override
        public void onClick(View v)
        {
            mRecordingState = "Ready";
            switchButtonVisibility();
        }
    });

由于某种奇怪的原因,它首先执行循环并在方法更改哪些按钮可见for之前播放声音。switchButtonVisibility();这似乎没有任何意义,因为该方法位于循环之上。有什么方法可以设置它,以便在执行循环并播放声音之前首先更改按钮的可见性?

4

1 回答 1

1

延迟执行,在视图上发布事件。这将确保在视图更新后立即执行操作:


    @Override
    public void onClick(View v) {
        mRecordingState = "Playing";
        switchButtonVisibility();

        mBtn_Play.post(new Runnable() {
            @Override
            public void run() {
                for (final int sound : mListRecordedSounds ) {
                    // play the sound here
                    ...
                }
            }
        });
    }

于 2017-12-04T14:34:47.187 回答