这篇文章将为大家详细讲解有关android10.0如何实现本地音乐播放？，小编觉得挺实用的，因此分享给大家做个参考，希望大家阅读完这篇文章后可以有所收获。
1.概述
本篇文章仅是android小白在写一个小程序，内容仅供参考，有很多不足之处希望各位大神指出，文章末尾有整个项目的下载，不需要币，只求帮你们解决到问题的同时收获到一颗小小的赞。这个项目中还有很多不足的地方，如：在按键中设置图片文字，这些正常的应该交给handler处理，我只是粗略地完成这个项目。测试环境：android10.0。实现：自动播放下一首，正常音乐的功能，全屏显示。
android10.0是内外分存了的，应用是没有权限读取内存的，需要在配置文件中application中加上属性：android:requestlegacyexternalstorage=“true”，不加可能可以读取歌曲，但是无法播放。
2.效果截图
截图显示不同是因为这不是同一时间截的，只是一个效果图
3.读取本地音乐以及保存歌曲
①先在androidmanifest文件里面配置权限
②目前基本上的手机使用静态权限是不够的，需要动态获取权限，因此需要在mainactivity里面动态获取，在oncreate方法里调用方法
private void check(){
if (build.version.sdk_int >= build.version_codes.m) {
if (checkselfpermission(manifest.permission.write_external_storage) != packagemanager.permission_granted ) {
requestpermissions(new string[]{manifest.permission.write_external_storage}, 1);
log.d(tag,"---------------------写权限不够-----------------");
}
if(checkselfpermission(manifest.permission.read_external_storage)!= packagemanager.permission_granted ){
requestpermissions(new string[]{manifest.permission.read_external_storage}, 2);
log.d(tag,"---------------------读权限不够-----------------");
}
}
}
③再去实现权限的回调方法，与activity的oncreate方法是同一级别的
@override
public void onrequestpermissionsresult(int requestcode, @nonnull string[] permissions, @nonnull int[] grantresults) {
super.onrequestpermissionsresult(requestcode, permissions, grantresults);
switch (requestcode) {
case 1:
if (grantresults.length > 0 && grantresults[0] == packagemanager.permission_granted) {
log.d(tag, "---------------------写权限够了-----------------------------");
}
break;
case 2:
if (grantresults.length > 0 && grantresults[0] == packagemanager.permission_granted) {
log.d(tag, "---------------------读权限够了-----------------------------");
}
break;
}
}
④创建一个工具类mp3info，用来保存音乐信息的，里面主要是一些get和set方法
public class mp3info {
private string url;//路径
private string title;//歌曲名
private string artist;//艺术家
private long duration;//歌曲时长
private long id;
private long album;//专辑图片
}
⑤创建一个musicutil类，通过contentporvider的接口获取歌曲信息
public class musicutil {
//获取专辑封面的ui
private static final string tag="musicutil";
private static final uri albumarturi=uri.parse("content://media/external/audio/albumart");
//生成歌曲列表
public static list getmp3infolist(context context){
cursor cursor=context.getcontentresolver().query(mediastore.audio.media.external_content_uri, null, null, null,null);
list mp3infolist=new arraylist<>();
while(cursor.movetonext()){
mp3info mp3info=new mp3info();
mp3info.set));//path
mp3info.settitle(cursor.getstring(cursor.getcolumnindex(mediastore.audio.media.title)));
mp3info.setartist(cursor.getstring(cursor.getcolumnindex(mediastore.audio.media.artist)));
mp3info.setduration(cursor.getlong(cursor.getcolumnindex(mediastore.audio.media.duration)));
mp3info.setid(cursor.getlong(cursor.getcolumnindex(mediastore.audio.media._id)));
mp3info.setalbum(cursor.getint(cursor.getcolumnindex(mediastore.audio.media.album_id)));
mp3infolist.add(mp3info);
}
return mp3infolist;
}
//格式化时间，转换为分/秒
public static string formattime(long time){
string min = time / (1000 * 60) "";
string sec = time % (1000 * 60) "";
if (min.length() < 2) {
min = "0" time / (1000 * 60) "";
} else {
min = time / (1000 * 60) "";
}
if (sec.length() == 4) {
sec = "0" (time % (1000 * 60)) "";
} else if (sec.length() == 3) {
sec = "00" (time % (1000 * 60)) "";
} else if (sec.length() == 2) {
sec = "000" (time % (1000 * 60)) "";
} else if (sec.length() == 1) {
sec = "0000" (time % (1000 * 60)) "";
}
return min ":" sec.trim().substring(0, 2);
}
//获取专辑图片，目前是只能获取手机自带歌曲的专辑图片，如果手机有酷狗，qq音乐之类的，可能无法获取专辑图片
//因为他们的uri不知道。
public bitmap getartwork(context context, long song_id, long album_id, boolean allowdefalut, boolean small){
if(album_id < 0) {
if(song_id < 0) {
bitmap bm = getartworkfromfile(context, song_id, -1);
if(bm != null) {
return bm;
}
}
if(allowdefalut) {
return getdefaultartwork(context, small);
}
return null;
}
contentresolver res = context.getcontentresolver();
uri uri = contenturis.withappendedid(albumarturi, album_id);
if(uri != null) {
inputstream in = null;
try {
in = res.openinputstream(uri);
bitmapfactory.options options = new bitmapfactory.options();
//先制定原始大小
options.insamplesize = 1;
//只进行大小判断
options.injustdecodebounds = true;
//调用此方法得到options得到图片的大小
bitmapfactory.decodestream(in, null, options);
/** 我们的目标是在你n pixel的画面上显示。 所以需要调用computesamplesize得到图片缩放的比例 **/
/** 这里的target为800是根据默认专辑图片大小决定的，800只是测试数字但是试验后发现完美的结合 **/
if(small){
options.insamplesize = computesamplesize(options, 40);
} else{
options.insamplesize = computesamplesize(options, 600);
}
// 我们得到了缩放比例，现在开始正式读入bitmap数据
options.injustdecodebounds = false;
options.indither = false;
options.inpreferredconfig = bitmap.config.argb_8888;
in = res.openinputstream(uri);
return bitmapfactory.decodestream(in, null, options);
} catch (filenotfoundexception e) {
bitmap bm = getartworkfromfile(context, song_id, album_id);
if(bm != null) {
if(bm.getconfig() == null) {
bm = bm.copy(bitmap.config.rgb_565, false);
if(bm == null && allowdefalut) {
return getdefaultartwork(context, small);
}
}
} else if(allowdefalut) {
bm = getdefaultartwork(context, small);
}
return bm;
} finally {
try {
if(in != null) {
in.close();
}
} catch (ioexception e) {
e.printstacktrace();
}
}
}
return null;
}
/**
* 从文件当中获取专辑封面位图
* @param context
* @param songid
* @param albumid
* @return
*/
private static bitmap getartworkfromfile(context context, long songid, long albumid){
bitmap bm = null;
if(albumid < 0 && songid < 0) {
throw new illegalargumentexception("---------------------" tag "must specify an album or a song id");
}
try {
bitmapfactory.options options = new bitmapfactory.options();
filedescriptor fd = null;
if(albumid < 0){
uri uri = uri.parse("content://media/external/audio/media/" songid "/albumart");
parcelfiledescriptor pfd = context.getcontentresolver().openfiledescriptor(uri, "r");
if(pfd != null) {
fd = pfd.getfiledescriptor();
}
} else {
uri uri = contenturis.withappendedid(albumarturi, albumid);
parcelfiledescriptor pfd = context.getcontentresolver().openfiledescriptor(uri, "r");
if(pfd != null) {
fd = pfd.getfiledescriptor();
}
}
options.insamplesize = 1;
// 只进行大小判断
options.injustdecodebounds = true;
// 调用此方法得到options得到图片大小
bitmapfactory.decodefiledescriptor(fd, null, options);
// 我们的目标是在800pixel的画面上显示
// 所以需要调用computesamplesize得到图片缩放的比例
options.insamplesize = 100;
// 我们得到了缩放的比例，现在开始正式读入bitmap数据
options.injustdecodebounds = false;
options.indither = false;
options.inpreferredconfig = bitmap.config.argb_8888;
//根据options参数，减少所需要的内存
bm = bitmapfactory.decodefiledescriptor(fd, null, options);
} catch (filenotfoundexception e) {
e.printstacktrace();
}
return bm;
}
/**
* 获取默认专辑图片
* @param context
* @return
*/
@suppresslint("resourcetype")
public static bitmap getdefaultartwork(context context, boolean small) {
bitmapfactory.options opts = new bitmapfactory.options();
opts.inpreferredconfig = bitmap.config.rgb_565;
if(small){ //返回小图片
//return
bitmapfactory.decodestream(context.getresources().openrawresource(r.drawable.default_picture), null, opts);
}
return bitmapfactory.decodestream(context.getresources().openrawresource(r.drawable.default_picture), null, opts);
}
/**
* 对图片进行合适的缩放
* @param options
* @param target
* @return
*/
public static int computesamplesize(bitmapfactory.options options, int target) {
int w = options.outwidth;
int h = options.outheight;
int candidatew = w / target;
int candidateh = h / target;
int candidate = math.max(candidatew, candidateh);
if(candidate == 0) {
return 1;
}
if(candidate > 1) {
if((w > target) && (w / candidate) < target) {
candidate -= 1;
}
}
if(candidate > 1) {
if((h > target) && (h / candidate) < target) {
candidate -= 1;
}
}
return candidate;
}
}
⑥为列表设置adapter，新建一个myadapter类继承baseadapter，然后在重写的getview里面设置显示的控件
@override
public view getview(int position, view convertview, viewgroup parent) {
if(convertview==null){
holder=new viewholder();
convertview=view.inflate(context, r.layout.list_item,null);
holder.tv_title=convertview.findviewbyid(r.id.tv_title);
holder.tv_artist=convertview.findviewbyid(r.id.tv_artist);
holder.tv_duration=convertview.findviewbyid(r.id.tv_duration);
holder.tv_position=convertview.findviewbyid(r.id.tv_position);
convertview.settag(holder);
}else {
holder= (viewholder) convertview.gettag();
}
holder.tv_title.settext(list.get(position).gettitle());
holder.tv_artist.settext(list.get(position).getartist());
long duration = list.get(position).getduration();
string time= musicutil.formattime(duration);
holder.tv_duration.settext(time);
holder.tv_position.settext(position 1 "");
if(currentitem == position){
holder.tv_title.setselected(true);
holder.tv_position.setselected(true);
holder.tv_duration.setselected(true);
holder.tv_artist.setselected(true);
}else{
holder.tv_title.setselected(false);
holder.tv_position.setselected(false);
holder.tv_duration.setselected(false);
holder.tv_artist.setselected(false);
}
return convertview;
}
class viewholder{
textview tv_title;//歌曲名
textview tv_artist;//歌手
textview tv_duration;//时长
textview tv_position;//序号
}
4.使用service实现后台播放
使用的是bindservice，这样service的生命周期就和activity的生命周期绑定在一起了。创建一个musicservice。注意：销毁service的时候需要将音乐对象release。
①service实现功能，在onbind方法里面实例化音乐播放对象
@override
public ibinder onbind(intent intent) {
log.d(tag,"onbind is call");
mybinder=new mybinder();
return mybinder;
}
②在mybinder()里面实现音乐的各种功能，使用的是内部类，初始化部分请看源代码包
public class mybinder extends binder{
private int index=0;//歌曲索引
//播放音乐
public void playmusic(int index){
this.index=index;
try {
file file=new file(list.get(this.index).get);
if(!file.exists()){
log.d(tag,"------------------------------文件不存在------------------------------");
return ;
}else{
log.d(tag,"------------------------------文件：" file.getpath() "存在 ------------------------------");
}
if(mediaplayer!=null){
mediaplayer.reset();
mediaplayer.release();
}
mediaplayer=new mediaplayer();
string str=list.get(this.index).get;
mediaplayer.setdatasource(str);
log.d(tag,list.get(this.index).get "");
mediaplayer.prepare();
mediaplayer.start();
} catch (ioexception e) {
e.printstacktrace();
}
}
//暂停音乐
public void pausemusic(){
if(mediaplayer.isplaying()){
mediaplayer.pause();
}
}
//关闭音乐
public void closemusic(){
if(mediaplayer!=null){
mediaplayer.release();
}
}
//下一首
public void nextmusic(){
if(index>=list.size()-1){
this.index=0;
}else{
this.index =1;
}
playmusic(this.index);
}
//上一首
public void preciousmusic(){
if(index<=0){
this.index=list.size()-1;
}else{
this.index-=1;
}
playmusic(this.index);
}
//获取歌曲时长
public int getprogress(int dex){
return (int)list.get(dex).getduration();
}
public int getprogress(){
return (int)list.get(index).getduration();
}
//获取当前播放位置
public int getplayposition(){
return mediaplayer.getcurrentposition();
}
//移动到当前点播放
public void seektoposition(int m){
mediaplayer.seekto(m);
}
}
③在mainactivity里面绑定
a.先实例化一个serviceconnection对象
private serviceconnection connection=new serviceconnection() {
@override
public void onserviceconnected(componentname name, ibinder service) {
mybinder= (musicservice.mybinder) service;
seekbar.setmax(mybinder.getprogress());
seekbar.setonseekbarchangelistener(new seekbar.onseekbarchangelistener() {
@override
public void onprogresschanged(seekbar seekbar, int progress, boolean fromuser) {
//这里是判断进度条移动是不是用户所为
if(fromuser){
mybinder.seektoposition(seekbar.getprogress());
}
}
@override
public void onstarttrackingtouch(seekbar seekbar) {
}
@override
public void onstoptrackingtouch(seekbar seekbar) {
}
});
handler.post(runnable);
log.d(tag, "service与activity已连接");
}
@override
public void onservicedisconnected(componentname name) {
}
};
b.还需要一个handler来控制ui组件的变化，实例化放在了oncreate方法里面。
c.用一个runnable对象进行seekbar的前进
private runnable runnable=new runnable() {
@override
public void run() {
seekbar.setprogress(mybinder.getplayposition());
tv_lefttime.settext(time.format(mybinder.getplayposition()) "");
tv_righttime.settext(time.format(mybinder.getprogress()-mybinder.getplayposition()) "");
if(mybinder.getprogress()-mybinder.getplayposition()<1000){//时间不够了自动触发下一首
runonuithread(new runnable() {//使用ui线程来触发按键点击事件，不知道这样有没有什么危害
@override
public void run() {
ib_next.performclick();
}
});
}
handler.postdelayed(runnable,1000);
}
};
d.在oncreate方法里进行绑定
mediaserviceintent =new intent(this,musicservice.class);//mediaserviceintent为一个intent bindservice(mediaserviceintent,connection,bind_auto_create);
5.使用notification通知栏通知
注意：：如果点击通知栏是从mainactivity跳转到mainactivity，需要在配置文件的activity android:name=".mainactivity"
android:launchmode=“singletask”，设置为单任务。
布局在源代码包里，在api26级以上需要使用notificationchannel
①设置通知所触发的pandingintent，通过action识别，action为自己定义的常量，setsound无声音。通过remoteviews去实现通知栏组件的按钮实现
//设置通知
private void setnotification(){
string channelid="cary";
if(build.version.sdk_int>=build.version_codes.o){
notificationchannel channel=new notificationchannel(channelid,"xxx",notificationmanager.importance_low);
manager.createnotificationchannel(channel);
}
intent intent=new intent(mainactivity.this,mainactivity.class);
pendingintent pi=pendingintent.getactivity(mainactivity.this,0,intent,0);
if (build.version.sdk_int >= build.version_codes.o) {
notify=new notification.builder(mainactivity.this,channelid)
.setwhen(system.currenttimemillis())
.setsound(null)
.build();
}
notify.icon=android.r.drawable.btn_star;
notify.contentintent=pi;
notify.contentview=remoteviews;
notify.flags=notification.flag_ongoing_event;
remoteviews.setonclickpendingintent(r.id.notice,pi);
//上一首
intent previntent=new intent(button_prev_id);
pendingintent prevpendingintent=pendingintent.getbroadcast(this,0,previntent,0);
remoteviews.setonclickpendingintent(r.id.widget_prev,prevpendingintent);
//播放暂停
intent playintent=new intent(button_play_id);
pendingintent playpendingintent=pendingintent.getbroadcast(this,0,playintent,0);
remoteviews.setonclickpendingintent(r.id.widget_play,playpendingintent);
//下一首
intent nextintent=new intent(button_next_id);
pendingintent nextpendingintent=pendingintent.getbroadcast(this,0,nextintent,0);
remoteviews.setonclickpendingintent(r.id.widget_next,nextpendingintent);
//关闭
intent closeintent=new intent(button_close_id);
pendingintent closependingintent=pendingintent.getbroadcast(this,0,closeintent,0);
remoteviews.setonclickpendingintent(r.id.widget_close,closependingintent);
}
②动态注册广播
//注册广播
private void initbuttonreceiver(){
buttonbroadcastreceiver=new buttonbroadcastreceiver();
intentfilter intentfilter=new intentfilter();
intentfilter.addaction(button_prev_id);
intentfilter.addaction(button_play_id);
intentfilter.addaction(button_next_id);
intentfilter.addaction(button_close_id);
registerreceiver(buttonbroadcastreceiver,intentfilter);
}
③显示广播，需要注意的是，每次在activity里面点击上一首或者下一首都需要调用这个方法，刷新通知栏的标题，以及状态专辑
//展示通知
private void shownotification(){
if(isplaying){
remoteviews.setimageviewresource(r.id.widget_play,r.drawable.stop);
}else{
remoteviews.setimageviewresource(r.id.widget_play,r.drawable.start);
}
remoteviews.setimageviewbitmap(r.id.widget_album,utils.getartwork(mainactivity.this,list.get(music_index).getid(),list.get(music_index).getalbum(),true,false));
remoteviews.setimageviewresource(r.id.widget_close,android.r.drawable.ic_menu_close_clear_cancel);
remoteviews.settextviewtext(r.id.widget_title,list.get(music_index).gettitle());
remoteviews.settextviewtext(r.id.widget_artist,list.get(music_index).getartist());
remoteviews.settextcolor(r.id.widget_title,color.black);
remoteviews.settextcolor(r.id.widget_artist,color.black);
notify.contentview=remoteviews;
manager.notify(100,notify);
}
④通知栏动作接收，使用的是内部类
public class buttonbroadcastreceiver extends broadcastreceiver{
@override
public void onreceive(context context, intent intent) {
string action=intent.getaction();
log.d(tag,"--------------------收到action:" action "--------------------------");
if(action.equals(button_prev_id)){
runonuithread(new runnable() {
@override
public void run() {
ib_precious.performclick();
return;
}
});
}
if(action.equals(button_play_id)){
runonuithread(new runnable() {
@override
public void run() {
ib_state.performclick();
return;
}
});
}
if(action.equals(button_next_id)){
runonuithread(new runnable() {
@override
public void run() {
ib_next.performclick();
return;
}
});
}
if(action.equals(button_close_id)){
handler.removecallbacks(runnable);
mybinder.closemusic();
unbindservice(connection);
if(remoteviews!=null){
manager.cancel(100);
}
unregisterreceiver(buttonbroadcastreceiver);
finish();
}
}
}
6.全屏显示
①在androidmanifest文件里面配置主题样式android:theme="@style/theme.appcompat.light.noactionbar">
然后在oncreate方法里在setcontentview(r.layout.activity_main);之前
设置：
if(build.version.sdk_int>=21){
view decorview=getwindow().getdecorview();
decorview.setsystemuivisibility(view.system_ui_flag_layout_fullscreen|view.system_ui_flag_layout_stable);
getwindow().setstatusbarcolor(color.transparent);
}
7.设置歌曲选中后的样式
①在res目录下的drawable资源下新建一个类型为selector的xml文件，里面设置属性
②在adapter里面设置getview
currentitem == position){
holder.tv_title.setselected(true);
holder.tv_position.setselected(true);
holder.tv_duration.setselected(true);
holder.tv_artist.setselected(true);
}else{
holder.tv_title.setselected(false);
holder.tv_position.setselected(false);
holder.tv_duration.setselected(false);
holder.tv_artist.setselected(false);
}
注意：在使用的时候可能需要手动去设置里面打开权限
关于android10.0如何实现本地音乐播放？就分享到这里了，希望以上内容可以对大家有一定的帮助，可以学到更多知识。如果觉得文章不错，可以把它分享出去让更多的人看到。
