Service-based music player

This is a service-based music player. The program's music will be played by the background service component. When the background playing status changes, the program sends a broadcast notification to the foreground activity update interface. When you click the foreground activity interface button or drag the progress bar, the system sends a broadcast notification to the background service to change the playing status and play the specified music.

Program running:

Program code:

Program Interface Class (musicbox. Java ):

Package COM. jph. musicbox; import COM. jph. util. constutil; import android. OS. bundle; import android. app. activity; import android. app. alertdialog; import android. content. broadcastreceiver; import android. content. context; import android. content. intent; import android. content. intentfilter; import android. view. layoutinflater; import android. view. menu; import android. view. menuitem; import android. view. view; import and Roid. view. view. onclicklistener; import android. widget. imagebutton; import android. widget. linearlayout; import android. widget. seekbar; import android. widget. seekbar. onseekbarchangelistener; import android. widget. textview;/*** describe: </BR> * </BR> service-based music broadcaster * </BR> This application mainly implements: * </BR> 1. play-related control information is sent through the foreground activity and transmitted to the background service in the form of broadcast * </BR>. The background service is responsible for playing music. * </BR> receives background broadcasts to update the song and singer names on the playback interface. * </BR> 2. the progress bar is used to display the current playback position. When you drag the progress bar, * </BR> controls the playing of music at the specified position through the onseekbarchangelistener event * </BR> mediaplayer in the background. * </BR> @ author jph * </BR> date: 2014.08.07 **/public class musicbox extends activity {imagebutton btnplayorpause, btnpre, btnnext; // progress bar static seekbar skbmusic; // obtain the title, text box textview title, and author; string [] titlestrs = new string [] {"taosheng still", "Rape flower ", "You are the one"}; string [] authorstrs = new string [] {"Mao Ning", "Jackie Chan", "unknown artist "}; // Boolean isplaying = false; @ overrideprotected void oncreate (bundl E savedinstancestate) {super. oncreate (savedinstancestate); setcontentview (R. layout. main); skbmusic = (seekbar) findviewbyid (R. id. skbmusic); skbmusic. setonseekbarchangelistener (schangelistener); btnnext = (imagebutton) findviewbyid (R. id. btnnext); btnplayorpause = (imagebutton) findviewbyid (R. id. btnplayorpause); btnpre = (imagebutton) findviewbyid (R. id. btnpre); btnnext. setonclicklistener (listener); btnplayorpause. seton Clicklistener (listener); btnpre. setonclicklistener (listener); Title = (textview) findviewbyid (R. id. title); author = (textview) findviewbyid (R. id. author); title. settext (titlestrs [0]); author. settext (authorstrs [0]); // register the receiver musicboxreceiver mreceiver = new musicboxreceiver (); intentfilter filter = new intentfilter (); filter. addaction (constutil. musicbox_action); registerreceiver (mreceiver, filter); // start backend serviceintent I Ntent = new intent (this, musicservice. class); startservice (intent);} onclicklistener listener = new onclicklistener () {@ overridepublic void onclick (view v) {// todo auto-generated method stubswitch (v. GETID () {case R. id. btnnext: // The next btnplayorpause. setbackgroundresource (R. drawable. state_pasue); sendbroadcasttoservice (constutil. state_next); isplaying = true; break; case R. id. btnplayorpause: // play or pause if (! Isplaying) {btnplayorpause. setbackgroundresource (R. drawable. state_pasue); sendbroadcasttoservice (constutil. state_play); isplaying = true;} else {btnplayorpause. setbackgroundresource (R. drawable. state_play); sendbroadcasttoservice (constutil. state_pause); isplaying = false;} break; case R. id. btnpre: // The Last btnplayorpause. setbackgroundresource (R. drawable. state_pasue); sendbroadcasttoservice (constutil. state_previous); isplaying = true; break; default: Break ;}};/*** seekbar progress change event */onseekbarchangelistener schangelistener = new onseekbarchangelistener () {@ overridepublic void onstoptrackingtouch (seekbar) {// todo auto-generated method stub // After the drag is stopped, control the mediaplayer to play music musicservice at the specified position. mediaplayer. seekto (seekbar. getprogress (); musicservice. ischanging = false ;}@ overridepublic void onstarttrackingtouch (seekbar) {// todo auto-generated method stubmusicservice. ischanging = true;} @ overridepublic void onprogresschanged (seekbar, int progress, Boolean fromuser) {// todo auto-generated method stub}; @ overridepublic Boolean oncreateoptionsmenu (menu) {// inflate the menu; this adds items to the action bar if it is present. menu. add (menu. none, constutil. menu_about, menu. none, "about"); menu. add (menu. none, constutil. menu_exit, menu. none, "exit"); Return true;}/*** send control broadcast to backend Service * @ Param state int state control status code **/protected void sendbroadcasttoservice (INT state) {// todo auto-generated method stubintent intent = new intent (); intent. setaction (constutil. musicservice_action); intent. putextra ("control", State); // send the broadcast sendbroadcast (intent) ;}@ overridepublic Boolean onoptionsitemselected (menuitem item) of the playback control to the background service) {// todo auto-generated method stubswitch (item. getitemid () {Case constutil. menu_about: layoutinflater Inflater = layoutinflater. from (this); linearlayout layout = (linearlayout) Inflater. inflate (R. layout. about, null); alertdialog dialog = new alertdialog. builder (this ). create (); dialog. settitle ("about"); dialog. seticon (R. drawable. ic_launcher); dialog. setview (layout); dialog. show (); break; Case constutil. menu_exit: sendbroadcasttoservice (constutil. state_stop); this. finish (); break; default: break;} return true ;} // create a broadcast receiver to receive the broadcast class musicboxreceiver extends broadcastreceiver {@ overridepublic void onreceive (context, intent) sent by the background service) {// todo auto-generated method stub // gets the current message in the intent. Current indicates the currently playing song int current = intent. getintextra ("current",-1); title. settext (titlestrs [current]); // update the music Title Author. settext (authorstrs [current]); // updated by music author }}}

Background services for music playback:

Musicservice. Java

Package COM. jph. musicbox; import Java. io. ioexception; import Java. util. timer; import Java. util. timertask; import COM. jph. util. constutil; import android. app. service; import android. content. broadcastreceiver; import android. content. context; import android. content. intent; import android. content. intentfilter; import android. content. res. assetfiledescriptor; import android. content. res. assetmanager; import android. me Dia. mediaplayer; import android. media. mediaplayer. oncompletionlistener; import android. OS. ibinder;/*** describe: </BR> * </BR> background service responsible for music playback * </BR> 1. you can play a specified music by receiving a broadcast from the foreground that controls the playback information. * </BR> 2. load music in the Assets Directory * </BR> 3. creates a listener for the mediaplayer completion event. When the current music is played * </BR>, the listener automatically plays the next music * </BR> 4. create a timer for each playing music to detect the playing progress * </BR> and update the progress bar * </BR> @ author jph * </BR> date: 2014.08.07 **/public class musicservice extends Service {T Extends mtimer; timertask mtimertask; static Boolean ischanging = false; // mutex variable to prevent degree conflicts when the timer and seekbar are dragged // create a media player object static mediaplayer; // create an asset manager object assetmanager; // an array that stores the music name string [] musics = new string [] {"taoshengyijiu-maoning.mp3", "youcaihua-chenglong.mp3 ", "You are the oneplay"}; // The current playing music int current = 0; // The current playing status int state = constutil. state_non; // record the timer running status Boolean istimerrunning = fa LSE; @ overridepublic void oncreate () {// todo auto-generated method stubsuper. oncreate (); // register the receiver musicserciereceiver receiver = new musicserciereceiver (); intentfilter filter = new intentfilter (); filter. addaction (constutil. musicservice_action); registerreceiver (receiver, filter); mediaplayer = new mediaplayer (); assetmanager = getassets (); // creates a listener for the mediaplayer completion event. setoncompletionlistener (New oncomplet Ionlistener () {@ overridepublic void oncompletion (mediaplayer MP) {// todo auto-generated method stub // mtimer. cancel (); // cancel the timer current ++; prepareandplay (current );}});} /*** load and play music ** @ Param index int index the index of the first music to play **/protected void prepareandplay (INT index) {// todo auto-generated method stubif (istimerrunning) {// If timer is running mtimer. cancel (); // cancel the timer istimerrunning = false;} If (index> 2) {current = index = 0;} If (index <0) {current = Index = 2;} // send broadcast stop foreground activity update interface intent = new intent (); intent. putextra ("current", index); intent. setaction (constutil. musicbox_action); sendbroadcast (intent); try {// obtain the assetfiledescriptor object assetfiledescriptor = assetmanager of the specified file in the Assets Directory. openfd (musics [current]); mediaplayer. reset (); // initialize the mediaplayer object mediaplayer. setdatasource (assetfiledescriptor. getfiledesc Riptor (), assetfiledescriptor. getstartoffset (), assetfiledescriptor. getlength (); // prepare to play the music mediaplayer. prepare (); // play the music mediaplayer. start (); // The getduration () method must be followed by the prepare () method. Otherwise, the attempt to call getduration without a valid mediaplayer exception musicbox will occur. skbmusic. setmax (mediaplayer. getduration (); // set the seekbar length} catch (ioexception e) {// todo auto-generated catch blocke. printstacktrace ();} // ---------- the timer records the playback progress --------- // Mtimer = new timer (); mtimertask = new timertask () {@ override public void run () {istimerrunning = true; If (ischanging = true) // when the user is dragging the progress bar, the return; musicbox. skbmusic. setprogress (mediaplayer. getcurrentposition () ;}}; // checks the playback progress of mtimer every 10 milliseconds. schedule (mtimertask, 0, 10) ;}@ overridepublic ibinder onbind (intent) {// todo auto-generated method stubreturn NULL;} // create a broadcast receiver for receiving Receive broadcast class musicserciereceiver extends broadcastreceiver {@ overridepublic void onreceive (context, intent) sent by the front-end activity {// todo auto-generated method stubint control = intent. getintextra ("control",-1); Switch (Control) {Case constutil. state_play: // play the music if (State = constutil. state_pause) {// if the original status is paused mediaplayer. start ();} else if (State! = Constutil. state_play) {prepareandplay (current);} state = constutil. state_play; break; Case constutil. state_pause: // pause if (State = constutil. state_play) {mediaplayer. pause (); State = constutil. state_pause;} break; Case constutil. state_stop: // stop playing if (State = constutil. state_play | state = constutil. state_pause) {mediaplayer. stop (); State = constutil. state_stop;} break; Case constutil. state_previous: // prepareandplay (-- current); State = constutil. state_play; break; Case constutil. state_next: // The next prepareandplay (++ current); State = constutil. state_play; break; default: break ;}}}}

Constant tool class (constutil. Java ):

Package COM. jph. util;/*** describe: </BR> * </BR> constant tool class * </BR> is mainly used for constants used by other class providers * </BR> @ author jph * </BR> date: 2014.08.07 **/public class constutil {// actionpublic static final string musicbox_action = "com. jph. musicbox. musicbox_action "; // actionpublic static final string musicservice_action =" com. jph. musicbox. musicservice_action "; // initialize flagpublic static final int state_non = 0x122; // flagpublic static final int state_play = 0x123; // pause the flagpublic static final int state_pause = 0x124; // stop the flagpublic static final int state_stop = 0x125; // flagpublic static final int state_previous = 0x126; // flagpublic static final int state_next = 0x127; // menu itemidpublic static final int menu_about = 0x200; // The itemidpublic static final int menu_exit = 0x201; Public constutil () {// todo auto-generated constructor stub }}

Configuration File: androidmanifest. xml:

<? XML version = "1.0" encoding = "UTF-8"?> <Manifest xmlns: Android = "http://schemas.android.com/apk/res/android" package = "com. jph. musicbox "Android: versioncode =" 1 "Android: versionname =" 1.0 "> <uses-SDK Android: minsdkversion =" 8 "Android: targetsdkversion = "18"/> <application Android: allowbackup = "true" Android: icon = "@ drawable/ic_launcher" Android: Label = "@ string/app_name" Android: theme = "@ style/apptheme"> <! -- Remove the title bar of the main interface --> <activity Android: Name = "com. jph. musicbox. musicbox "Android: Label =" @ string/app_name "Android: theme =" @ Android: style/theme. black. notitlebar "> <intent-filter> <action Android: Name =" android. intent. action. main "/> <category Android: Name =" android. intent. category. launcher "/> </intent-filter> </activity> <! -- Register musicservice --> <service android: Name = "com. jph. musicbox. musicservice"> </service> </Application> </manifest>