Java 如何使媒体播放器同时读取内部和外部存储
我根据自己观看的教程开发了一款音乐播放器应用程序 当我在没有SD卡的设备上运行时 它崩溃了。所以我不能发布它,所以我可以添加或更改什么 这将使它能够从内部存储器中读取音乐 Java类Java 如何使媒体播放器同时读取内部和外部存储,java,android,android-sdcard,Java,Android,Android Sdcard,我根据自己观看的教程开发了一款音乐播放器应用程序 当我在没有SD卡的设备上运行时 它崩溃了。所以我不能发布它,所以我可以添加或更改什么 这将使它能够从内部存储器中读取音乐 Java类 package com.example.playaudioexample; import android.app.ListActivity; import android.content.Context; import android.database.Cursor; import android.media.M
package com.example.playaudioexample;
import android.app.ListActivity;
import android.content.Context;
import android.database.Cursor;
import android.media.MediaPlayer;
import android.os.Handler;
import android.provider.MediaStore;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageButton;
import android.widget.ListView;
import android.widget.SeekBar;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
import android.widget.Toast;
import java.io.IOException;
import java.math.BigDecimal;
public class PlayAudioExample extends ListActivity {
private static final int UPDATE_FREQUENCY = 500;
private static final int STEP_VALUE = 4000;
private MediaCursorAdapter mediaAdapter = null;
private TextView selelctedFile = null;
private SeekBar seekbar = null;
private MediaPlayer player = null;
private ImageButton playButton = null;
private ImageButton prevButton = null;
private ImageButton nextButton = null;
private ImageButton floatButton = null;
private ImageButton floatButton2 = null;
private boolean isStarted = true;
private String currentFile = "";
private boolean isMoveingSeekBar = false;
private final Handler handler = new Handler();
private final Runnable updatePositionRunnable = new Runnable() {
public void run() {
updatePosition();
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.content_play_audio_example);
selelctedFile = (TextView) findViewById(R.id.selectedfile);
seekbar = (SeekBar) findViewById(R.id.seekbar);
playButton = (ImageButton) findViewById(R.id.play);
prevButton = (ImageButton) findViewById(R.id.prev);
nextButton = (ImageButton) findViewById(R.id.next);
floatButton = (ImageButton) findViewById(R.id.imageinfo);
floatButton2 = (ImageButton)findViewById(R.id.imageMessage);
floatButton2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(),
"CONTACT:gabriel.agbese2001@gmail.com",Toast.LENGTH_LONG).show();
}
});
floatButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(),
"Developed by:Gabriel Agbese",Toast.LENGTH_LONG).show();
}
});
player = new MediaPlayer();
player.setOnCompletionListener(onCompletion);
player.setOnErrorListener(onError);
seekbar.setOnSeekBarChangeListener(seekBarChanged);
Cursor cursor = getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, null, null, null);
if (null != cursor) {
cursor.moveToFirst();
mediaAdapter = new MediaCursorAdapter(this, R.layout.listitem, cursor);
setListAdapter(mediaAdapter);
playButton.setOnClickListener(onButtonClick);
nextButton.setOnClickListener(onButtonClick);
prevButton.setOnClickListener(onButtonClick);
}
}
@Override
protected void onListItemClick(ListView list, View view, int position, long id) {
super.onListItemClick(list, view, position, id);
currentFile = (String) view.getTag();
startPlay(currentFile);
}
@Override
protected void onDestroy() {
super.onDestroy();
handler.removeCallbacks(updatePositionRunnable);
player.stop();
player.reset();
player.release();
player = null;
}
private void startPlay(String file) {
Log.i("Selected: ", file);
selelctedFile.setText(file);
seekbar.setProgress(0);
player.stop();
player.reset();
try {
player.setDataSource(file);
player.prepare();
player.start();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
seekbar.setMax(player.getDuration());
playButton.setImageResource(android.R.drawable.ic_media_pause);
updatePosition();
isStarted = true;
}
private void stopPlay() {
player.stop();
player.reset();
playButton.setImageResource(android.R.drawable.ic_media_play);
handler.removeCallbacks(updatePositionRunnable);
seekbar.setProgress(0);
isStarted = false;
}
private void updatePosition() {
handler.removeCallbacks(updatePositionRunnable);
seekbar.setProgress(player.getCurrentPosition());
handler.postDelayed(updatePositionRunnable, UPDATE_FREQUENCY);
}
private class MediaCursorAdapter extends SimpleCursorAdapter {
public MediaCursorAdapter(Context context, int layout, Cursor c) {
super(context, layout, c,
new String[]{MediaStore.MediaColumns.DISPLAY_NAME, MediaStore.MediaColumns.TITLE, MediaStore.Audio.AudioColumns.DURATION},
new int[]{R.id.displayname, R.id.title, R.id.duration});
}
@Override
public void bindView(View view, Context context, Cursor cursor) {
TextView title = (TextView) view.findViewById(R.id.title);
TextView name = (TextView) view.findViewById(R.id.displayname);
TextView duration = (TextView) view.findViewById(R.id.duration);
name.setText(cursor.getString(
cursor.getColumnIndex(MediaStore.MediaColumns.DISPLAY_NAME)));
title.setText(cursor.getString(
cursor.getColumnIndex(MediaStore.MediaColumns.TITLE)));
long durationInMs = Long.parseLong(cursor.getString(
cursor.getColumnIndex(MediaStore.Audio.AudioColumns.DURATION)));
double durationInMin = ((double) durationInMs / 1000.0) / 60.0;
durationInMin = new BigDecimal(Double.toString(durationInMin)).setScale(2, BigDecimal.ROUND_UP).doubleValue();
duration.setText("" + durationInMin);
view.setTag(cursor.getString(cursor.getColumnIndex(MediaStore.MediaColumns.DATA)));
}
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
LayoutInflater inflater = LayoutInflater.from(context);
View v = inflater.inflate(R.layout.listitem, parent, false);
bindView(v, context, cursor);
return v;
}
}
private View.OnClickListener onButtonClick = new View.OnClickListener() {
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.play: {
if (player.isPlaying()) {
handler.removeCallbacks(updatePositionRunnable);
player.pause();
playButton.setImageResource(android.R.drawable.ic_media_play);
} else {
if (isStarted) {
player.start();
playButton.setImageResource(android.R.drawable.ic_media_pause);
updatePosition();
} else {
startPlay(currentFile);
}
}
break;
}
case R.id.next: {
int seekto = player.getCurrentPosition() + STEP_VALUE;
if (seekto > player.getDuration())
seekto = player.getDuration();
player.pause();
player.seekTo(seekto);
player.start();
break;
}
case R.id.prev: {
int seekto = player.getCurrentPosition() - STEP_VALUE;
if (seekto < 0)
seekto = 0;
player.pause();
player.seekTo(seekto);
player.start();
break;
}
}
}
};
private MediaPlayer.OnCompletionListener onCompletion = new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mp) {
stopPlay();
}
};
private MediaPlayer.OnErrorListener onError = new MediaPlayer.OnErrorListener() {
@Override
public boolean onError(MediaPlayer mp, int what, int extra) {
return false;
}
};
private SeekBar.OnSeekBarChangeListener seekBarChanged = new SeekBar.OnSeekBarChangeListener() {
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
isMoveingSeekBar = false;
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
isMoveingSeekBar = true;
}
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
if (isMoveingSeekBar) {
player.seekTo(progress);
Log.i("OnSeekBarChangeListener", "onProgressChanged");
}
}
};
}
package com.example.playadioexample;
导入android.app.ListActivity;
导入android.content.Context;
导入android.database.Cursor;
导入android.media.MediaPlayer;
导入android.os.Handler;
导入android.provider.MediaStore;
导入android.support.v7.app.AppActivity;
导入android.os.Bundle;
导入android.support.v7.widget.Toolbar;
导入android.util.Log;
导入android.view.LayoutInflater;
导入android.view.Menu;
导入android.view.MenuItem;
导入android.view.view;
导入android.view.ViewGroup;
导入android.widget.ImageButton;
导入android.widget.ListView;
导入android.widget.SeekBar;
导入android.widget.SimpleCursorAdapter;
导入android.widget.TextView;
导入android.widget.Toast;
导入java.io.IOException;
导入java.math.BigDecimal;
公共类PlayAudioExample扩展了ListActivity{
私有静态最终整数更新频率=500;
私有静态最终整数步长_值=4000;
私有MediaCursorAdapter mediaAdapter=null;
私有TextView selelctedFile=null;
私有SeekBar SeekBar=null;
私有媒体播放器=null;
私有ImageButton playButton=null;
private ImageButton prevButton=null;
private ImageButton nextButton=null;
私有ImageButton floatButton=null;
私有ImageButton floatButton2=null;
私有布尔值isStarted=true;
私有字符串currentFile=“”;
私有布尔值IsMovingSeekbar=false;
私有最终处理程序=新处理程序();
private final Runnable updatePositionRunnable=new Runnable(){
公开募捐{
updatePosition();
}
};
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.content\u play\u audio\u示例);
selelctedFile=(TextView)findViewById(R.id.selectedfile);
seekbar=(seekbar)findViewById(R.id.seekbar);
playButton=(ImageButton)findViewById(R.id.play);
prevButton=(ImageButton)findViewById(R.id.prev);
nextButton=(ImageButton)findViewById(R.id.next);
floatButton=(ImageButton)findViewById(R.id.imageinfo);
floatButton2=(ImageButton)findViewById(R.id.imageMessage);
floatButton2.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图v){
Toast.makeText(getApplicationContext(),
联系人:加布里埃尔。agbese2001@gmail.com“,Toast.LENGTH_LONG).show();
}
});
floatButton.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图v){
Toast.makeText(getApplicationContext(),
“开发人:加布里埃尔·阿格贝斯”,Toast.LENGTH_LONG.show();
}
});
player=新媒体播放器();
player.setOnCompletionListener(onCompletion);
player.setOneRorListener(OneRor);
seekbar.setonseekbarchaneglistener(seekBarChanged);
Cursor Cursor=getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,null,null,null);
如果(null!=光标){
cursor.moveToFirst();
mediaAdapter=新的MediaCursorAdapter(this,R.layout.listitem,cursor);
setListAdapter(mediaAdapter);
playButton.setOnClickListener(onButtonClick);
setOnClickListener(onButtonClick);
prevButton.setOnClickListener(onButtonClick);
}
}
@凌驾
受保护的void onListItemClick(列表视图列表、视图视图、整数位置、长id){
super.onListItemClick(列表、视图、位置、id);
currentFile=(String)view.getTag();
开始播放(当前文件);
}
@凌驾
受保护的空onDestroy(){
super.ondestory();
removeCallbacks(updatePositionRunnable);
player.stop();
player.reset();
player.release();
player=null;
}
私有void startPlay(字符串文件){
Log.i(“选定:”,文件);
selectedfile.setText(文件);
seekbar.setProgress(0);
player.stop();
player.reset();
试一试{
player.setDataSource(文件);
player.prepare();
player.start();
}捕获(IllegalArgumentException e){
e、 printStackTrace();
}捕获(非法状态){
e、 printStackTrace();
}捕获(IOE异常){
e、 printStackTrace();
}
seekbar.setMax(player.getDuration());
playButton.setImageResource(android.R.drawable.ic\u media\u pause);
updatePosition();
IsStart=true;
}
私人空间{
player.stop();
player.reset();
playButton.setImageResource(android.R.drawable.ic\u media\u play);
removeCallbacks(updatePositionRunnable);
seekbar.setProgress(0);
isStarted=false;
}
私有void updatePosition(){
removeCallbacks(updatePositionRunnable);
seekbar.setProgress(player.getCurrentPosition());
postDelayed(updatePositionRunnable,更新频率);
}
私有类MediaCursorAdapter扩展了SimpleCursorAdapter{
公共媒体游标适配器(上下文上下文、int布局、游标c){
超级(上下文、布局、c、,
新字符串[]{MediaStore.MediaColumns.DISPLAY_NAME,MediaStore.MediaColumns.TITLE,MediaStore.Audio.AudioColumns.DURATION},
新的int[]{R.id.displayname,R.id.title,R.id.duration});
}
@凌驾
公共void bindView(视图、上下文上下文、光标){
TextView title=(TextView)view.findViewById(R.id.title);
TextView name=(TextView)view.findViewById(R.id.displayname);
TextView duration=(TextView)view.findViewById(R.id.duration);
name.setText(cursor.getString(
cursor.getColumnIndex(MediaStore.MediaColumns.DISPLAY_NAME));
title.setText(cursor.getString(
光标。
<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:background="#0a0b0e"
android:orientation="vertical"
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=".PlayAudioExample">
<ListView
android:id="@android:id/list"
android:background="#f0fffdfd"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textColor="@android:color/black"
android:layout_weight="1.0" />
<LinearLayout
android:layout_width="wrap_content"
android:background="#f7262624"
android:layout_height="wrap_content">
<ImageButton
android:layout_width="65dp"
android:layout_height="65dp"
android:background="@drawable/oval"
android:id="@+id/imageinfo"
android:src="@android:drawable/ic_dialog_info"
android:layout_gravity="center_horizontal" />
<ImageButton
android:layout_width="65dp"
android:layout_height="65dp"
android:background="@drawable/oval2"
android:id="@+id/imageMessage"
android:src="@android:drawable/ic_dialog_email" />
</LinearLayout>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:backgroundTint="#f7262624"
android:background="@android:drawable/screen_background_light"
android:orientation="vertical"
android:padding="10dip">
<TextView
android:id="@+id/selectedfile"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:ellipsize="middle"
android:gravity="center_horizontal"
android:singleLine="true"
android:text="No file selected"
android:textColor="@android:color/black" />
<SeekBar
android:id="@+id/seekbar"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:max="100"
android:paddingBottom="10dip" />
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="@android:drawable/screen_background_light"
android:gravity="center"
android:backgroundTint="#ca030b03"
android:orientation="horizontal">
<ImageButton
android:id="@+id/prev"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#000"
android:src="@android:drawable/ic_media_previous" />
<ImageButton
android:id="@+id/play"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@android:drawable/ic_media_play" />
<ImageButton
android:id="@+id/next"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#000"
android:src="@android:drawable/ic_media_next" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
<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:background="#0a0b0e"
android:orientation="vertical"
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=".PlayAudioExample">
<ListView
android:id="@android:id/list"
android:background="#f0fffdfd"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textColor="@android:color/black"
android:layout_weight="1.0" />
<LinearLayout
android:layout_width="wrap_content"
android:background="#f7262624"
android:layout_height="wrap_content">
<ImageButton
android:layout_width="65dp"
android:layout_height="65dp"
android:background="@drawable/oval"
android:id="@+id/imageinfo"
android:src="@android:drawable/ic_dialog_info"
android:layout_gravity="center_horizontal" />
<ImageButton
android:layout_width="65dp"
android:layout_height="65dp"
android:background="@drawable/oval2"
android:id="@+id/imageMessage"
android:src="@android:drawable/ic_dialog_email" />
</LinearLayout>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:backgroundTint="#f7262624"
android:background="@android:drawable/screen_background_light"
android:orientation="vertical"
android:padding="10dip">
<TextView
android:id="@+id/selectedfile"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:ellipsize="middle"
android:gravity="center_horizontal"
android:singleLine="true"
android:text="No file selected"
android:textColor="@android:color/black" />
<SeekBar
android:id="@+id/seekbar"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:max="100"
android:paddingBottom="10dip" />
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="@android:drawable/screen_background_light"
android:gravity="center"
android:backgroundTint="#ca030b03"
android:orientation="horizontal">
<ImageButton
android:id="@+id/prev"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#000"
android:src="@android:drawable/ic_media_previous" />
<ImageButton
android:id="@+id/play"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@android:drawable/ic_media_play" />
<ImageButton
android:id="@+id/next"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#000"
android:src="@android:drawable/ic_media_next" />
</LinearLayout>
</LinearLayout>
</LinearLayout>