MediaPlayer 准备播放时如何显示 ProgressBar？

Question

我想在 MediaPlayer 准备播放和 MediaPlayer 开始播放 ProgressBar 时显示 ProgressBar 消失。 这是我的代码

  public class MainActivity extends Activity {
  String path="http://live.mp3quran.net:8006/;";
  Button play_button, pause_button;
  MediaPlayer player =new MediaPlayer();
  private ProgressBar mProgress;
   @Override public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    play_button=(Button)findViewById(R.id.play_button);
    pause_button=(Button)findViewById(R.id.pause_button);
    mProgress=(ProgressBar)findViewById(R.id.progressBar);
    mProgress.setVisibility(View.INVISIBLE);
    play_button.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        mProgress.setVisibility(View.VISIBLE);
        try {

            player.setDataSource(path);
            player.prepare();
            player.start();
        } catch (IOException e) {
            e.printStackTrace();
        }
        finally {
            if(mProgress.getVisibility()==View.VISIBLE)
                mProgress.setVisibility(View.INVISIBLE);
        }

    }

});

pause_button.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        player.stop();
        player.reset();
    }
});

}
}

我的 XML 文件代码

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin">
<Button android:id="@+id/play_button"
 android:layout_width="120px"
    android:layout_height="60px"
    android:layout_marginTop="60px"
    android:gravity="center"
    android:text="Play" />
<Button android:id="@+id/pause_button"
    android:layout_width="120px"
    android:layout_height="60px"
    android:layout_alignParentRight="true"
    android:layout_marginTop="60px"
    android:text="Pause" />
  <ProgressBar
    style="?android:attr/progressBarStyleLarge"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/progressBar"
    android:layout_alignBottom="@+id/text_shown"
    android:layout_toRightOf="@+id/play_button"
    android:layout_toLeftOf="@+id/pause_button"
    android:max="100"
    android:progress="20"
    android:layout_toStartOf="@+id/pause_button" />
   </RelativeLayout>

我的问题是 ProgressBar 没有出现。

我已经尝试过这个解决方案

How can i show a ProgressBar when mediaPlayer is prepairing to play

但这无济于事。

Answer 1

你可以这样使用

 final ProgressDialog ringProgressDialog = ProgressDialog.show(this, "Please wait ...", "Fetching your contact..", true);
    ringProgressDialog.setCancelable(true);
    new Thread(new Runnable() {
        @Override
        public void run() {
            try {
                // Here you should write your time consuming task...
                // Let the progress ring for 10 seconds...
                readContact();
            //  Thread.sleep(300);
            } catch (Exception e) {

            }
            ringProgressDialog.dismiss();
        }
    }).start();