如何在android中播放、暂停和停止歌曲?
我正在为Android制作一个应用程序,我制作了三个按钮来播放、暂停和停止 我的“播放”和“暂停”按钮已设置,因此当我单击“播放”按钮时,它将不可见,并显示“暂停”按钮,反之亦然 当我点击播放按钮时,它工作正常,但在我点击暂停按钮后,它会给我一个错误 代码如下所示如何在android中播放、暂停和停止歌曲?,android,Android,我正在为Android制作一个应用程序,我制作了三个按钮来播放、暂停和停止 我的“播放”和“暂停”按钮已设置,因此当我单击“播放”按钮时,它将不可见,并显示“暂停”按钮,反之亦然 当我点击播放按钮时,它工作正常,但在我点击暂停按钮后,它会给我一个错误 代码如下所示 package com.mpIlango; import java.io.IOException; import java.util.ArrayList; import android.app.Activity; impo
package com.mpIlango;
import java.io.IOException;
import java.util.ArrayList;
import android.app.Activity;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;
public class MpIlangoActivity extends Activity implements OnCheckedChangeListener {
/** Called when the activity is first created. */
MediaPlayer song1,song2,song3;
int whatsong = 0;
private ArrayList<Integer> songIds;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
RadioGroup rgMusic = (RadioGroup) findViewById(R.id.rgMusic);
songIds = new ArrayList<Integer>();
songIds.add(R.raw.fluet);
songIds.add(R.raw.airtel);
songIds.add(R.raw.titanic);
final Button bPlay = (Button) findViewById(R.id.bPlay);
final Button bStop = (Button) findViewById(R.id.bStop);
final Button bPause = (Button) findViewById(R.id.bPause);
bPause.setVisibility(View.GONE);
rgMusic.setOnCheckedChangeListener(this);
bPlay.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(song1!=null) {
song1.release();
}
if(song2!=null) {
song2.release();
}
if(song3!=null) {
song3.release();
}
switch (whatsong) {
case 1:
try {
song1 = MediaPlayer.create(MpIlangoActivity.this, songIds.get(0));
song1.prepare();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
song1.start();
bPlay.setVisibility(View.GONE);
bPause.setVisibility(View.VISIBLE);
break;
case 2:
try {
song2 = MediaPlayer.create(MpIlangoActivity.this, songIds.get(1));
song2.prepare();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
song2.start();
bPlay.setVisibility(View.GONE);
bPause.setVisibility(View.VISIBLE);
break;
case 3:
try {
song3 = MediaPlayer.create(MpIlangoActivity.this, songIds.get(2));
song3.prepare();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
song3.start();
bPlay.setVisibility(View.GONE);
bPause.setVisibility(View.VISIBLE);
break;
}
}
});
bPause.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
bPlay.setVisibility(View.VISIBLE);
bPause.setVisibility(View.GONE);
if(song1.isPlaying()){
song1.pause();
}
if(song2.isPlaying()){
song2.pause();
}
if(song3.isPlaying()){
song3.pause();
}
}
});
bStop.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(song1!=null){
song1.release();
}
if(song2!=null){
song2.release();
}
if(song3!=null){
song3.release();
}
}
});;
}
@Override
public void onCheckedChanged(RadioGroup group, int rbId) {
switch (rbId) {
case R.id.rbMusic1:
whatsong = 1;
break;
case R.id.rbMusic2:
whatsong = 2;
break;
case R.id.rbMusic3:
whatsong = 3;
break;
}
}
}
package com.mpIlango;
导入java.io.IOException;
导入java.util.ArrayList;
导入android.app.Activity;
导入android.media.MediaPlayer;
导入android.os.Bundle;
导入android.view.view;
导入android.widget.Button;
导入android.widget.RadioGroup;
导入android.widget.RadioGroup.OnCheckedChangeListener;
公共类MpIlangoActivity扩展活动实现OnCheckedChangeListener{
/**在首次创建活动时调用*/
MediaPlayer歌曲1、歌曲2、歌曲3;
int whatsong=0;
私人ArrayList songIds;
@凌驾
创建时的公共void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
射线组rgMusic=(射线组)findViewById(R.id.rgMusic);
songIds=newarraylist();
songIds.add(R.raw.fluet);
songIds.add(R.raw.airtel);
songIds.add(R.raw.泰坦尼克号);
最终按钮bPlay=(按钮)findViewById(R.id.bPlay);
最终按钮bStop=(按钮)findViewById(R.id.bStop);
最终按钮bPause=(按钮)findViewById(R.id.bPause);
b原因设置可见性(视图已消失);
rgMusic.setOnCheckedChangeListener(此);
bPlay.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图v){
if(song1!=null){
松1.释放();
}
if(song2!=null){
松2.释放();
}
if(song3!=null){
松3.释放();
}
交换机(whatsong){
案例1:
试一试{
song1=MediaPlayer.create(MpIlangoActivity.this,songIds.get(0));
歌曲1.prepare();
}捕获(非法状态){
e、 printStackTrace();
}捕获(IOE){
e、 printStackTrace();
}
song1.start();
bPlay.setVisibility(View.GONE);
b原因设置可见性(视图可见);
打破
案例2:
试一试{
song2=MediaPlayer.create(MpIlangoActivity.this,songIds.get(1));
歌曲2.prepare();
}捕获(非法状态){
e、 printStackTrace();
}捕获(IOE){
e、 printStackTrace();
}
song2.start();
bPlay.setVisibility(View.GONE);
b原因设置可见性(视图可见);
打破
案例3:
试一试{
song3=MediaPlayer.create(MpIlangoActivity.this,songIds.get(2));
歌曲3.准备();
}捕获(非法状态){
e、 printStackTrace();
}捕获(IOE){
e、 printStackTrace();
}
song3.start();
bPlay.setVisibility(View.GONE);
b原因设置可见性(视图可见);
打破
}
}
});
bPause.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图v){
bPlay.setVisibility(View.VISIBLE);
b原因设置可见性(视图已消失);
if(song1.isPlaying()){
歌曲1.暂停();
}
if(song2.isPlaying()){
歌曲2.暂停();
}
if(song3.isPlaying()){
暂停();
}
}
});
bStop.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图v){
if(song1!=null){
松1.释放();
}
if(song2!=null){
松2.释放();
}
if(song3!=null){
松3.释放();
}
}
});;
}
@凌驾
检查更改后的公共无效(放射组组,int rbId){
开关(rbId){
案例R.id.rbMusic1:
whatsong=1;
打破
案例R.id.RBC2:
whatsong=2;
打破
案例R.id.RBC3:
whatsong=3;
打破
}
}
}
我猜你在这里的某个地方遇到了NullPointerException
if(song1.isPlaying()){
song1.pause();
}
if(song2.isPlaying()){
song2.pause();
}
if(song3.isPlaying()){
song3.pause();
}
这就是问题所在,你也可以在这里使用开关
switch (whatsong) {
case 1:
if(song1.isPlaying()){
song1.pause();
}
或者在其他地方初始化你的歌曲,以确保它们永远不会为空
我还建议只使用一个MediaPlayer
MediaPlayer song;
bPlay代码:
if(song!=null) {
song.release();
}
switch (whatsong) {
case 1:
try {
song = MediaPlayer.create(MpIlangoActivity.this, songIds.get(0));
song.prepare();
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
song.start();
bPlay.setVisibility(View.GONE);
bPause.setVisibility(View.VISIBLE);
b原因代码:
bPlay.setVisibility(View.VISIBLE);
bPause.setVisibility(View.GONE);
if(song != null && song.isPlaying()){
song.pause();
}
所有这些代码都未经测试 这是一个soundmanager/audiomanager课程,希望它能帮助您或为您指明正确的方向;)
import java.util.HashMap;
导入java.util.Random;
导入android.content.Context;
导入android.media.AudioManager;
导入android.media.MediaPlayer;
导入android.media.SoundPool;
公共类声音管理器{
公共布尔音频;
公共布尔audioSoundFX;
公共有声音乐;
私人音乐池;
私有HashMap-mSoundPoolMap;
私人音频经理;
私有上下文mContex
import java.util.HashMap;
import java.util.Random;
import android.content.Context;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.media.SoundPool;
public class SoundManager {
public boolean audio;
public boolean audioSoundFX;
public boolean audioMusic;
private SoundPool mSoundPool;
private HashMap<Integer, Integer> mSoundPoolMap;
private AudioManager mAudioManager;
private Context mContext;
private Random random = new Random();
private MediaPlayer menuMusic;
private MediaPlayer gameMusic;
private int menuMusicCurrentPos = 0;
private int gameMusicCurrentPos = 0;
public static final SoundManager INSTANCE = new SoundManager();
private SoundManager() {
}
public void setAudio(boolean audioOn){
if(audioOn){
audio = true;
}
if(!audioOn) {
audio = false;
}
}
public void setSoundFX(boolean soundFX){
if(soundFX){
audioSoundFX = true;
}
if(!soundFX) {
audioSoundFX = false;
}
}
public void setMusic(boolean music){
if(music){
audioMusic = true;
}
if(!music) {
audioMusic = false;
}
}
public void initSounds(Context theContext) {
if (mSoundPool == null){
mContext = theContext;
mSoundPool = new SoundPool(4, AudioManager.STREAM_MUSIC, 0);
mSoundPoolMap = new HashMap<Integer, Integer>();
mAudioManager = (AudioManager)mContext.getSystemService(Context.AUDIO_SERVICE);
mSoundPoolMap.put(1, mSoundPool.load(mContext, R.raw.ufo_laser, 1));
mSoundPoolMap.put(2, mSoundPool.load(mContext, R.raw.enemy_hunter_one_laser, 1));
mSoundPoolMap.put(3, mSoundPool.load(mContext, R.raw.enemyhuntertwomissile, 1));
mSoundPoolMap.put(4, mSoundPool.load(mContext, R.raw.enemy_hunter_three_laser, 1));
mSoundPoolMap.put(5, mSoundPool.load(mContext, R.raw.enemy_drone, 1));
mSoundPoolMap.put(6, mSoundPool.load(mContext, R.raw.kamikaze, 1));
mSoundPoolMap.put(14, mSoundPool.load(mContext, R.raw.exploastroidshard, 1));
mSoundPoolMap.put(11, mSoundPool.load(mContext, R.raw.health, 1));
mSoundPoolMap.put(12, mSoundPool.load(mContext, R.raw.energy, 1));
mSoundPoolMap.put(13, mSoundPool.load(mContext, R.raw.shield, 1));
mSoundPoolMap.put(15, mSoundPool.load(mContext, R.raw.gameover, 1));
mSoundPoolMap.put(16, mSoundPool.load(mContext, R.raw.gameoverexplo, 1));
mSoundPoolMap.put(17, mSoundPool.load(mContext, R.raw.menu_beep, 1));
mSoundPoolMap.put(20, mSoundPool.load(mContext, R.raw.menu_beep, 1));
menuMusic = MediaPlayer.create(mContext, R.raw.musicmenu);
}
}
public void playSound(int index, boolean pitching, int loop){
if(audioSoundFX == true && audio == true){
float randomPitch;
if (pitching){
randomPitch = (float)(random.nextInt(3) + 9) / 10;
}else{
randomPitch = 1;
}
float streamVolume = mAudioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
streamVolume = streamVolume / mAudioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
mSoundPool.play((Integer) mSoundPoolMap.get(index), streamVolume, streamVolume, 1, loop, randomPitch);
}
}
public void playMenuMusic(){
if(audioMusic == true && audio == true){
if (menuMusic == null){
if(MediaPlayer.create(mContext, R.raw.musicmenu) != null) {
menuMusic = MediaPlayer.create(mContext, R.raw.musicmenu);
if(menuMusicCurrentPos != 0){
menuMusic.seekTo(menuMusicCurrentPos);
}
menuMusic.start();
menuMusic.setVolume(1f , 1f);
menuMusic.setLooping(true);
}
}
}
}
public void releaseMenuMusic(){
if(menuMusic != null){
this.menuMusicCurrentPos = menuMusic.getCurrentPosition();
menuMusic.release();
menuMusic = null;
}
}
public void playGameMusic(){
if(audioMusic == true && audio == true){
if (gameMusic == null){
gameMusic = MediaPlayer.create(mContext, R.raw.music_game);
if(menuMusicCurrentPos != 0){
gameMusic.seekTo(gameMusicCurrentPos);
}
gameMusic.start();
gameMusic.setVolume(1f , 1f);
gameMusic.setLooping(true);
}
}
}
public void releaseGameMusic(){
if(gameMusic != null){
this.gameMusicCurrentPos = gameMusic.getCurrentPosition();
gameMusic.release();
gameMusic = null;
}
}
Mediaplayer.pause();
length=Mediaplayer.getCurrentPosition();
Mediaplayer.seekTo(length);
Mediaplayer.start();