16 读取音乐文件

• 所需权限

  <!--Sd读写权限  -->    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

• java代码:

  package com.qf.day16_contentresolver_music_demo3;import java.io.File;import android.annotation.SuppressLint;import android.app.Activity;import android.content.ContentResolver;import android.content.Intent;import android.database.Cursor;import android.net.Uri;import android.os.Bundle;import android.provider.MediaStore;import android.provider.MediaStore.Audio.Media;import android.view.View;import android.widget.AdapterView;import android.widget.AdapterView.OnItemClickListener;import android.widget.ListView;import android.widget.SimpleCursorAdapter;import android.widget.TextView;/** *  * 获取音乐 * */public class MainActivity extends Activity {    private ListView lv;    private TextView tv;    private ContentResolver contentResolver;    //获取音频的Uri对象    private Uri uri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;    SimpleCursorAdapter adapter;    @SuppressLint("NewApi")    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        lv = (ListView) findViewById(R.id.lv);        tv = (TextView) findViewById(R.id.tv);        contentResolver = getContentResolver();        //获取Sd卡里音乐的数据          //Media._ID 如果要用SimpleCursorAdaptet必须要查找此字段        //Media.DISPLAY_NAME 音乐名 XXX.MP4        //Media.DATA 绝对路径         //Media.TITLE  音乐名 XXX        Cursor cursor = contentResolver.query(uri,                 new String[]{Media._ID,                Media.DISPLAY_NAME,                Media.DATA,                Media.TITLE}, null, null, null);         adapter = new SimpleCursorAdapter                (MainActivity.this, R.layout.item,                         cursor, new String[]{Media.DISPLAY_NAME,                        Media.DATA,                        Media.TITLE},                         new int[]{R.id.tv_name,R.id.tv_data,R.id.tv_title},                        SimpleCursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);        lv.setAdapter(adapter);        lv.setEmptyView(tv);        lv.setOnItemClickListener(new OnItemClickListener() {            @Override            public void onItemClick(AdapterView<?> parent, View view,                    int position, long id) {                // TODO Auto-generated method stub                //获取当前位置的数据                Cursor c = (Cursor) adapter.getItem(position);                //获取音乐的 路径                String path = c.getString(c.getColumnIndex(Media.DATA));                //播放音乐                Intent intent= new Intent();                intent.setAction(Intent.ACTION_VIEW);                intent.setDataAndType(Uri.fromFile(new File(path)), "audio/*");                startActivity(intent);            }        });    }}

• layout 布局代码:
  activity_main2.xml:

  <RelativeLayout 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=".MainActivity" >    <ListView        android:id="@+id/lv"        android:layout_width="match_parent"        android:layout_height="match_parent"       />    <TextView         android:id="@+id/tv"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textSize="30sp"        android:textColor="#f00"        android:text="暂无数据"        /></RelativeLayout>

  item.xml:
  填充list布局

  <?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" >    <ImageView        android:id="@+id/iv"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:src="@drawable/ic_launcher" />    <TextView        android:id="@+id/tv_name"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_toRightOf="@id/iv"        android:singleLine="true"        android:text="aaa" />    <TextView        android:id="@+id/tv_data"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_below="@id/tv_name"        android:layout_toRightOf="@id/iv"        android:singleLine="true"        android:text="aaa" />    <TextView        android:id="@+id/tv_title"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_below="@id/tv_data"        android:layout_toRightOf="@id/iv"        android:singleLine="true"        android:text="aaa" /></RelativeLayout>