【具体问题】Only the original thread that created a view hierarchy can touch its views

timer = new Timer();
                timer.schedule(new TimerTask() {
                    @Override
                    public void run() {
                        if (!isSeekBarChanging){
                            currentPosition = mediaPlayer.getCurrentPosition();// 记录当前播放位置
                            seekBar.setProgress(currentPosition);
                            tv_current_position.setText(currentPosition+"");
                        }
                    }
                },0,1000);
           

问题出在这里：

tv_current_position.setText(currentPosition+"");

此时是在子线程中，要转移到UI线程中设置

那如何在UI线程中动态设置

textview的值呢？

通过handle实现：

private Handler handler = new Handler(){
        @Override
        public void handleMessage(@NonNull Message msg) {
            super.handleMessage(msg);
            tv_current_position.setText(currentPosition+"");
        }
    };

timer.schedule(new TimerTask() {
                    @Override
                    public void run() {
                        if (!isSeekBarChanging){
                            currentPosition = mediaPlayer.getCurrentPosition();// 记录当前播放位置
                            seekBar.setProgress(currentPosition);
                            // 发送消息，通知UI线程刷新视图
                            handler.sendEmptyMessage(0);
                        }
                    }
                },0,1000);