Android——音乐播放器完善——进度条显示当前播放进度，加可拖动进度条（未待解决完问题）

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    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"
    tools:context="com.example.chenshuai.myapplication.ActivityMusic"
    android:orientation="vertical">
    <ProgressBar
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="@android:style/Widget.ProgressBar.Horizontal"
        android:id="@+id/pb"
        />

    <SeekBar
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/sbr" />
    <TextView
        android:layout_width="match_parent"
        android:layout_height="40sp"
        android:text="播放状态"
        android:textSize="20sp"
        android:gravity="center_horizontal"
        android:id="@+id/tv_1"/>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="播放"
            android:onClick="play_onclick"/>
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="暂停"
            android:onClick="pause_onclick"/>
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="停止"
            android:onClick="stop_onclick"/>
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="退出"
            android:onClick="exit_onclick"/>
    </LinearLayout>

</LinearLayout>

package com.example.chenshuai.myapplication;

import android.app.Service;
import android.content.Intent;
import android.media.MediaPlayer;
import android.os.Binder;
import android.os.IBinder;



public class MyServiceMusic extends Service {


    public MyServiceMusic() {


    }

    public class Mybind extends Binder
    {
        //获取歌曲长度
        public int getMusicDuration()
        {
            int rtn = 0;
            if (mediaPlayer != null)
            {
                rtn = mediaPlayer.getDuration();
            }

            return rtn;
        }
        //获取当前播放进度
        public int getMusicCurrentPosition()
        {
            int rtn = 0;
            if (mediaPlayer != null)
            {
                rtn = mediaPlayer.getCurrentPosition();

            }

            return rtn;
        }

        public void seekTo(int position)
        {
            if (mediaPlayer != null)
            {
                mediaPlayer.seekTo(position);
            }
        }

    }


    @Override
    public IBinder onBind(Intent intent) {
        // TODO: Return the communication channel to the service.
        //throw new UnsupportedOperationException("Not yet implemented");
        return  new Mybind();
    }
    private MediaPlayer mediaPlayer;

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        //获取意图传递的信息
        String action = intent.getStringExtra("action");

        switch (action)
        {
            case "play":
                if (mediaPlayer == null)
                {
                    mediaPlayer = MediaPlayer.create(this,R.raw.onceagain);


                }
                mediaPlayer.start();

                break;
            case "stop":
                if (mediaPlayer !=null)
                {
                    mediaPlayer.stop();
                    mediaPlayer.reset();
                    mediaPlayer.release();
                    mediaPlayer = null;
                }
                break;
            case "pause":
                if (mediaPlayer !=null && mediaPlayer.isPlaying())
                {
                    mediaPlayer.pause();
                }
                break;
        }
        return super.onStartCommand(intent, flags, startId);
    }
}

package com.example.chenshuai.myapplication;

import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.ProgressBar;
import android.widget.SeekBar;
import android.widget.TextView;

public class ActivityMusicservice extends AppCompatActivity {

    TextView tv_1;
    ProgressBar pb;
    SeekBar sbr;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_activity_music);

        tv_1 = (TextView)findViewById(R.id.tv_1);

        tv_1.setText("播放状态11：停止播放。。。");
        pb = (ProgressBar)findViewById(R.id.pb);
        sbr = (SeekBar)findViewById(R.id.sbr);

    }

    ServiceConnection serviceConnection;
    MyServiceMusic.Mybind mybind;

    public void play_onclick(View view)
    {
        Intent intent = new Intent(this,MyServiceMusic.class);

        intent.putExtra("action","play");

        startService(intent);

        tv_1.setText("播放状态11：正在播放。。。");

        if (serviceConnection == null) {
            serviceConnection = new ServiceConnection() {
                @Override
                public void onServiceConnected(ComponentName name, IBinder service) {

                    mybind = (MyServiceMusic.Mybind) service;

                    //设置进度条的最大长度
                    int max = mybind.getMusicDuration();
                    pb.setMax(max);

                    sbr.setMax(max);
                    sbr.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
                        @Override
                        public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {

                            mybind.seekTo(progress);
                        }

                        @Override
                        public void onStartTrackingTouch(SeekBar seekBar) {

                        }

                        @Override
                        public void onStopTrackingTouch(SeekBar seekBar) {

                        }
                    });

                    //连接之后启动子线程设置当前进度
                  new Thread()
                    {
                        public void run()
                        {

                            //改变当前进度条的值
                            //设置当前进度
                            while (true) {
                                pb.setProgress(mybind.getMusicCurrentPosition());
                               // sbr.setProgress(mybind.getMusicCurrentPosition());

                                try {
                                    Thread.sleep(100);
                                } catch (Exception e) {

                                    e.printStackTrace();
                                }
                            }
                        }

                    }.start();

                }

                @Override
                public void onServiceDisconnected(ComponentName name) {

                }
            };

            //以绑定方式连接服务
            bindService(intent, serviceConnection, Context.BIND_AUTO_CREATE);

        }

    }

    public void stop_onclick(View view)
    {
        Intent intent = new Intent(this,MyServiceMusic.class);

        intent.putExtra("action","stop");

        startService(intent);

        tv_1.setText("播放状态11：停止播放。。。");
    }
    public void pause_onclick(View view)
    {
        Intent intent = new Intent(this, MyServiceMusic.class);

        intent.putExtra("action","pause");

        startService(intent);

        tv_1.setText("播放状态11：暂停播放。。。");


    }
    public void exit_onclick(View view)
    {
        stop_onclick(view);
        finish();
    }
}

<service
            android:name=".MyServiceMusic"
            android:enabled="true"
            android:exported="true" />