我正在制作一个应用程序来播放设备存储器中的音频文件,我有一个seek条,它每秒钟检查音频文件的进度(播放了多长时间),并相应地更新seekbar。
音频通过在前台运行的服务播放,并显示音频正在播放的通知。
当音频结束时,我注意到处理程序仍在循环中,我想在音频结束后结束处理程序。
我目前尝试的是从处理程序运行的runnable内部结束处理程序,因为我不确定如何结束它。
主活动,在这里我从listview处理onclick,在这里您可以选择一个音频文件,还可以处理seekbar更新。
import androidx.appcompat.app.AppCompatActivity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.database.Cursor;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.provider.MediaStore;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SeekBar;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
import java.util.concurrent.TimeUnit;
public class MainActivity extends AppCompatActivity {
SeekBar musicProgBar;
Handler progBarHandler = null;
Runnable r = null;
private MP3Service.MyBinder myService = null;
TextView progressText = null;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
musicProgBar = findViewById(R.id.musicProgressBar);
progressText = findViewById(R.id.progressText);
final ListView lv = (ListView) findViewById(R.id.musicList);
Cursor cursor = getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
null,
MediaStore.Audio.Media.IS_MUSIC + "!= 0",
null,
null);
progBarHandler = new Handler();
final int progBarDelay = 1000; // delay for the handler, making it repeat itself only every 1000 miliseconds (1 second)
lv.setAdapter(new SimpleCursorAdapter(this,
android.R.layout.simple_list_item_1,
cursor,
new String[] { MediaStore.Audio.Media.DATA},
new int[] { android.R.id.text1 }));
Intent tempIntent = new Intent(this, MP3Service.class);
startService(tempIntent);
bindService(tempIntent, serviceConnection, 0);
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> myAdapter,
View myView,
int myItemInt,
long myLong) {
Cursor c = (Cursor) lv.getItemAtPosition(myItemInt);
String uri = c.getString(c.getColumnIndex(MediaStore.Audio.Media.DATA));
Log.d("g53mdp", uri);
if (myService.fetchPlayerState() != MP3Player.MP3PlayerState.STOPPED)
myService.stopMusic();
myService.loadMusic(uri);
myService.playMusic();
musicProgBar.setMax(myService.fetchDuration()); // set the max value of the seekbar to be the duration of the song
r = new Runnable()
{
@Override
public void run()
{
int tempInt = myService.fetchProgress();
Log.d("progress ticking", tempInt + " " + musicProgBar.getProgress());
musicProgBar.setProgress(tempInt); // sets the current progress of the seekbar to be the progress of the song
long minutes = TimeUnit.MILLISECONDS.toMinutes(tempInt);
long seconds = TimeUnit.MILLISECONDS.toSeconds(tempInt);
if (seconds >= 60)
seconds = seconds - 60;
String tempString = minutes + ":" + seconds;
progressText.setText(tempString);
progBarHandler.postDelayed(this, progBarDelay);
if (musicProgBar.getProgress() == myService.fetchDuration())
progBarHandler.removeCallbacks(this);
}
};
progBarHandler.post(r);
}});
}
private ServiceConnection serviceConnection = new ServiceConnection()
{
@Override
public void onServiceConnected(ComponentName name, IBinder service)
{
myService = (MP3Service.MyBinder) service;
}
@Override
public void onServiceDisconnected(ComponentName name)
{
myService = null;
}
};
public void playButClicked(View view)
{
myService.playMusic();
}
public void pauseButClicked(View view)
{
myService.pauseMusic();
}
public void stopButClicked(View view)
{
myService.stopMusic();
}
@Override
protected void onDestroy()
{
unbindService(serviceConnection);
progBarHandler.removeCallbacks(r);
super.onDestroy();
}
}
奇怪的是,在ondestroy()中,我确实使用removecallbacks来结束处理程序,而且效果很好。我知道它在runnable r中调用removecallbacks,这是通过调试和日志记录确认的。还尝试了实现一个方法,该方法专门用于删除处理程序并调用它,但运气不好。还尝试使用return。
我正在挣扎的部分是
r = new Runnable()
{
@Override
public void run()
{
int tempInt = myService.fetchProgress();
Log.d("progress ticking", tempInt + " " + musicProgBar.getProgress());
musicProgBar.setProgress(tempInt); // sets the current progress of the seekbar to be the progress of the song
long minutes = TimeUnit.MILLISECONDS.toMinutes(tempInt);
long seconds = TimeUnit.MILLISECONDS.toSeconds(tempInt);
if (seconds >= 60)
seconds = seconds % 60;
String tempString = minutes + ":" + seconds;
progressText.setText(tempString);
progBarHandler.postDelayed(this, progBarDelay);
if (musicProgBar.getProgress() == myService.fetchDuration())
progBarHandler.removeCallbacks(this);
}
};
progBarHandler.post(r);
}});
处理音乐播放器和播放音乐的服务
import android.app.Notification;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.os.Binder;
import android.os.Build;
import android.os.Handler;
import android.os.IBinder;
import android.util.Log;
import androidx.annotation.Nullable;
import androidx.core.app.NotificationCompat;
public class MP3Service extends Service
{
public static MP3Service instance = null; // implementing singleton by instantiating a reference to the instance
private final String SERVICE_ID = "100"; // id for the service
public static boolean isRunning = false; //
NotificationManager notificationManager = null;
int notificationID = 001;
private final IBinder binder = new MyBinder();
MP3Player mainPlayer;
@Nullable
@Override
public IBinder onBind(Intent intent)
{
return binder;
}
@Override
public void onRebind(Intent intent)
{
// TODO: implement Rebind for screen orientation change
}
@Override
public void onCreate()
{
instance = this;
isRunning = true;
notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
mainPlayer = new MP3Player();
super.onCreate();
Handler handler = new Handler();
}
@Override
public void onDestroy()
{
isRunning = false;
instance = null;
notificationManager.cancel(notificationID);
}
public void createNotification()
{
CharSequence name = "MP3 Notification";
String description = "Displays a notification when a song is playing";
int importance = NotificationManager.IMPORTANCE_DEFAULT;
NotificationChannel channel = new NotificationChannel(SERVICE_ID, name, importance);
channel.setDescription(description);
notificationManager.createNotificationChannel(channel);
Intent intent = new Intent(this, MainActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
// when the user clicks the notification, this will bring them to the activity
PendingIntent navToMainActivity = PendingIntent.getActivity(this, 0, intent, 0);
// sets up the info and details for the notification
final NotificationCompat.Builder mNotification = new NotificationCompat.Builder(this, SERVICE_ID)
.setSmallIcon(R.drawable.ic_launcher_background)
.setContentTitle("MP3 Player")
.setContentText("Playing music")
.setContentIntent(navToMainActivity)
.setPriority(NotificationCompat.PRIORITY_DEFAULT);
startForeground(notificationID, mNotification.build());
}
public void removeNotification()
{
stopForeground(false);
notificationManager.cancelAll();
}
public class MyBinder extends Binder
{
public void loadMusic(String filePath)
{
mainPlayer.load(filePath);
}
public void playMusic()
{
mainPlayer.play();
createNotification();
}
public void pauseMusic()
{
mainPlayer.pause();
removeNotification();
}
public void stopMusic()
{
mainPlayer.stop();
removeNotification();
}
public MP3Player.MP3PlayerState fetchPlayerState()
{
return mainPlayer.getState();
}
public int fetchDuration()
{
return mainPlayer.getDuration();
}
public int fetchProgress()
{
return mainPlayer.getProgress();
}
}
}
提前感谢您的帮助,如有需要,我很乐意提供更多信息
编辑:将runnable之外的progbarhandler.postdelay()更改为简单的progbarhandler.post()
2条答案
按热度按时间ltqd579y1#
我认为您未能停止处理程序的唯一原因是不断调用
progBarHandler.postDelayed(this, progBarDelay);
,您需要检查它为什么仍在运行。oxcyiej72#
通过向runnable引入不同类型的if语句,成功地使其工作,如
出于某种原因,使用.fetchduration()和.fetchprogress()似乎永远不会互相均衡,因此更改if语句是有效的。