思路
首先是扫描本地所有的音频文件,然后全部装进集合当中,接下来就是用ListView展示在屏幕上,大概就是这几个步骤了,接下来细讲
创建一个容器
进行过数据解析的朋友都应该知道JavaBean吧,用来装载解析出来的数据,我们这里同样也要创建一个JavaBean,用来装载扫描到的音频文件,具体的代码是:
1. <pre name="code" class="html">package com.duanlian.mymusicplayerdemo.bean;
2.
3. /**
4. * Created by user on 2016/6/24.
5. * 放置音乐
6. */
7. public class Song {
8. /**
9. * 歌手
10. */
11. public String singer;
12. /**
13. * 歌曲名
14. */
15. public String song;
16. /**
17. * 歌曲的地址
18. */
19. public String path;
20. /**
21. * 歌曲长度
22. */
23. public int duration;
24. /**
25. * 歌曲的大小
26. */
27. public long size;
28. }
创建一个用来扫描本地音频的工具类
类里面定义一个扫描本地音频的方法,其返回值是一个list集合,集合里面装的泛型就是上一步创建的JavaBean,具体代码如下:
1. package com.duanlian.mymusicplayerdemo.utils;
2.
3. import android.content.Context;
4. import android.database.Cursor;
5. import android.provider.MediaStore;
6.
7. import com.duanlian.mymusicplayerdemo.bean.Song;
8.
9. import java.util.ArrayList;
10. import java.util.List;
11.
12.
13. /**
14. * 音乐工具类,
15. */
16. public class MusicUtils {
17. /**
18. * 扫描系统里面的音频文件,返回一个list集合
19. */
20. <Song> getMusicData(Context context) {
21. <Song> list = new ArrayList<Song>();
22. // 媒体库查询语句(写一个工具类MusicUtils)
23. cursor = context.getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, null,
24. null, MediaStore.Audio.AudioColumns.IS_MUSIC);
25. if (cursor != null) {
26. while (cursor.moveToNext()) {
27. song = new Song();
28. song.song = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME));
29. song.singer = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST));
30. song.path = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA));
31. song.duration = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DURATION));
32. song.size = cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE));
33. > 1000 * 800) {
34. // 注释部分是切割标题,分离出歌曲名和歌手 (本地媒体库读取的歌曲信息不规范)
35. if (song.song.contains("-")) {
36. str = song.song.split("-");
37. song.singer = str[0];
38. song.song = str[1];
39. }
40. list.add(song);
41. }
42. }
43. // 释放资源
44. cursor.close();
45. }
46.
47. return list;
48. }
49.
50. /**
51. * 定义一个方法用来格式化获取到的时间
52. */
53. public static String formatTime(int time) {
54. < 10) {
55. return time / 1000 / 60 + ":0" + time / 1000 % 60;
56.
57. } else {
58. return time / 1000 / 60 + ":" + time / 1000 % 60;
59. }
60.
61. }
62. }
1. <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
数据展示
ListView展示数据需要配合Adapter一起使用,而Adapter里面需要传一个上下文,一个数据源,上下文直接能拿到,数据源上面我们已经拿到了,接下来是写ListView和Adapter的编写,先看看MainActivity的布局文件,非常简单:
1. <?xml version="1.0" encoding="utf-8"?>
2. <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
3. xmlns:tools="http://schemas.android.com/tools"
4. android:layout_width="match_parent"
5. android:layout_height="match_parent"
6. tools:context="com.duanlian.mymusicplayerdemo.MainActivity">
7.
8. <TextView
9. android:id="@+id/main_textview"
10. android:layout_width="match_parent"
11. android:layout_height="40dp"
12. android:gravity="center"
13. android:text="我的音乐" />
14. <ListView
15. android:id="@+id/main_listview"
16. android:layout_below="@+id/main_textview"
17. android:layout_width="match_parent"
18. android:layout_height="match_parent"/>
19. </RelativeLayout>
接下来就是MainActivity里面的编写,具体代码:
1. package com.duanlian.mymusicplayerdemo;
2.
3. import android.support.v7.app.AppCompatActivity;
4. import android.os.Bundle;
5. import android.widget.ListView;
6.
7. import com.duanlian.mymusicplayerdemo.adapter.MyAdapter;
8. import com.duanlian.mymusicplayerdemo.bean.Song;
9. import com.duanlian.mymusicplayerdemo.utils.MusicUtils;
10.
11. import java.util.ArrayList;
12. import java.util.List;
13.
14. public class MainActivity extends AppCompatActivity {
15.
16. private ListView mListView;
17. <Song> list;
18. private MyAdapter adapter;
19.
20. @Override
21. protected void onCreate(Bundle savedInstanceState) {
22. super.onCreate(savedInstanceState);
23. setContentView(R.layout.activity_main);
24. initView();
25. }
26.
27. /**
28. * 初始化view
29. */
30. private void initView() {
31. mListView = (ListView) findViewById(R.id.main_listview);
32. list = new ArrayList<>();
33. //把扫描到的音乐赋值给list
34. list = MusicUtils.getMusicData(this);
35. adapter = new MyAdapter(this,list);
36. mListView.setAdapter(adapter);
37. }
38. }
是不是很简单,就定义一个ListView并且绑定Adapter,接下来就Adapter得编写:
1. package com.duanlian.mymusicplayerdemo.adapter;
2.
3. import android.content.Context;
4. import android.view.View;
5. import android.view.ViewGroup;
6. import android.widget.BaseAdapter;
7. import android.widget.TextView;
8.
9. import com.duanlian.mymusicplayerdemo.MainActivity;
10. import com.duanlian.mymusicplayerdemo.R;
11. import com.duanlian.mymusicplayerdemo.bean.Song;
12. import com.duanlian.mymusicplayerdemo.utils.MusicUtils;
13.
14. import java.util.List;
15.
16. public class MyAdapter extends BaseAdapter {
17. private Context context;
18. <Song> list;
19. <Song> list) {
20. this.context = mainActivity;
21. this.list = list;
22.
23. }
24.
25. @Override
26. public int getCount() {
27. return list.size();
28. }
29.
30. @Override
31. public Object getItem(int i) {
32. return list.get(i);
33. }
34.
35. @Override
36. public long getItemId(int i) {
37. return i;
38. }
39.
40. @Override
41. public View getView(int i, View view, ViewGroup viewGroup) {
42. holder = null;
43. view == null) {
44. holder = new ViewHolder();
45. //引入布局
46. view = View.inflate(context, R.layout.item_music_listview, null);
47. //实例化对象
48. holder.song = (TextView) view.findViewById(R.id.item_mymusic_song);
49. holder.singer = (TextView) view.findViewById(R.id.item_mymusic_singer);
50. holder.duration = (TextView) view.findViewById(R.id.item_mymusic_duration);
51. holder.position = (TextView) view.findViewById(R.id.item_mymusic_postion);
52. view.setTag(holder);
53. } else {
54. holder = (ViewHolder) view.getTag();
55. }
56. //给控件赋值
57. holder.song.setText(list.get(i).song.toString());
58. holder.singer.setText(list.get(i).singer.toString());
59. //时间需要转换一下
60. duration = list.get(i).duration;
61. time = MusicUtils.formatTime(duration);
62. holder.duration.setText(time);
63. holder.position.setText(i+1+"");
64.
65. return view;
66. }
67. class ViewHolder{
68. TextView song;//歌曲名
69. TextView singer;//歌手
70. TextView duration;//时长
71. TextView position;//序号
72.
73. }
74.
75. }
ListView都需要一个item,具体代码:
1. <?xml version="1.0" encoding="utf-8"?>
2. <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
3. android:layout_width="match_parent"
4. android:layout_height="110dp"
5. android:orientation="horizontal"
6. android:gravity="center_vertical"
7. android:padding="5dp">
8. <TextView
9. android:id="@+id/item_mymusic_postion"
10. android:layout_width="wrap_content"
11. android:layout_height="wrap_content"
12. android:layout_margin="10dp"
13. android:text="1"
14. android:gravity="center"
15. android:textColor="#0d0c0c"
16. android:textSize="18sp" />
17.
18. <RelativeLayout
19. android:layout_width="wrap_content"
20. android:layout_height="wrap_content"
21. android:layout_marginLeft="20dp"
22. >
23.
24. <TextView
25. android:id="@+id/item_mymusic_song"
26. android:layout_width="wrap_content"
27. android:layout_height="wrap_content"
28. android:text="歌曲名"
29. android:textColor="#0d0c0c"
30. android:textSize="20dp" />
31.
32.
33. <TextView
34. android:id="@+id/item_mymusic_singer"
35. android:layout_width="wrap_content"
36. android:layout_height="wrap_content"
37. android:layout_below="@+id/item_mymusic_song"
38. android:text="歌手"
39. android:textColor="#0d0c0c"
40. android:textSize="15sp" />
41.
42. <TextView
43. android:id="@+id/item_mymusic_duration"
44. android:layout_width="wrap_content"
45. android:layout_height="wrap_content"
46. android:layout_below="@+id/item_mymusic_song"
47. android:layout_marginLeft="15dp"
48. android:textColor="#0d0c0c"
49. android:layout_toRightOf="@+id/item_mymusic_singer"
50. android:text="时间"
51. android:textSize="15sp" />
52. </RelativeLayout>
53.
54. </LinearLayout>