java - Syntactical Errors in my Android media player -

these syntactical errors, , don't know how figure out,

current_song cannot resolved variable

multiple markers @ line, song_url cannot resolved variable

how resolve above errors. unable access song_url , current_song in methods, instance in,

next.setonclicklistener(new view.onclicklistener(){ @override         public void onclick(view v) {             // todo auto-generated method stub             mp.stop();             ++current_song;             mp.setdatasource(song_url[current_song]);             mp.start();         }     }); 

my complete code,

public class jsonmedia extends activity { private mediaplayer mp; button play, pause, next;  public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.jsonview);      mp = new mediaplayer();     mp.setaudiostreamtype(audiomanager.stream_music);     play = (button) findviewbyid(r.id.play);     pause = (button) findviewbyid(r.id.pause);     next = (button) findviewbyid(r.id.next);      try {         // create url desired page         url url = new url("http://reallifethug.webs.com/temp_list.txt");         bufferedreader in = new bufferedreader(new inputstreamreader(                 url.openstream()));          int ch, current_song = 0, eof = -1; // end of file         string list[];          string str = "";         while ((ch = in.read()) != eof)             str += (char) ch;         in.close();          list = str.split("\n");          (ch = 0; ch < list.length; ++ch)             list[ch] += "\n";          string song_name[] = new string[list.length];         string song_url[] = new string[list.length];          (int = 0; < list.length; i++) {             song_name[i] = "";             song_url[i] = "";             int = 0;             char c;              while ((c = list[i].charat(a++)) != ' ')                 song_name[i] += c;              while ((c = list[i].charat(a++)) != '\n')                 song_url[i] += c;         }         mp.setdatasource(song_url[current_song]);     } catch (illegalargumentexception e) {         // todo auto-generated catch block         e.printstacktrace();     } catch (securityexception e) {         // todo auto-generated catch block         e.printstacktrace();     } catch (illegalstateexception e) {         // todo auto-generated catch block         e.printstacktrace();     } catch (ioexception e) {         // todo auto-generated catch block         e.printstacktrace();     }     mp.prepareasync();     play.setenabled(false);     mp.setonpreparedlistener(new mediaplayer.onpreparedlistener() {         @override         public void onprepared(mediaplayer mp) {             // todo auto-generated method stub             play.setenabled(true);         }     });      play.setonclicklistener(new view.onclicklistener() {          @override         public void onclick(view v) {             // todo auto-generated method stub             mp.start();         }     });      pause.setonclicklistener(new view.onclicklistener() {          @override         public void onclick(view v) {             // todo auto-generated method stub             mp.pause();         }     });      next.setonclicklistener(new view.onclicklistener() {          @override         public void onclick(view v) {             // todo auto-generated method stub             mp.stop();             ++current_song;             mp.setdatasource(song_url[current_song]);             mp.start();         }     });  }  @override public boolean oncreateoptionsmenu(menu menu) {     // inflate menu; adds items action bar if present.     getmenuinflater().inflate(r.menu.jsonmedia, menu);     return true; }  } 

log cat, 05-18 17:37:14.272: d/androidruntime(486): shutting down vm 05-18 17:37:14.272: w/dalvikvm(486): threadid=1: thread exiting uncaught exception (group=0x40015560) 05-18 17:37:14.291: e/androidruntime(486): fatal exception: main 05-18 17:37:14.291: e/androidruntime(486): java.lang.nullpointerexception 05-18 17:37:14.291: e/androidruntime(486): @ com.hiphop.streamingmediaplayer.jsonmedia$4.onclick(jsonmedia.java:114) 05-18 17:37:14.291: e/androidruntime(486): @ android.view.view.performclick(view.java:2485) 05-18 17:37:14.291: e/androidruntime(486): @ android.view.view$performclick.run(view.java:9080) 05-18 17:37:14.291: e/androidruntime(486): @ android.os.handler.handlecallback(handler.java:587) 05-18 17:37:14.291: e/androidruntime(486): @ android.os.handler.dispatchmessage(handler.java:92) 05-18 17:37:14.291: e/androidruntime(486): @ android.os.looper.loop(looper.java:123) 05-18 17:37:14.291: e/androidruntime(486): @ android.app.activitythread.main(activitythread.java:3683) 05-18 17:37:14.291: e/androidruntime(486): @ java.lang.reflect.method.invokenative(native method) 05-18 17:37:14.291: e/androidruntime(486): @ java.lang.reflect.method.invoke(method.java:507) 05-18 17:37:14.291: e/androidruntime(486): @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:839) 05-18 17:37:14.291: e/androidruntime(486): @ com.android.internal.os.zygoteinit.main(zygoteinit.java:597) 05-18 17:37:14.291: e/androidruntime(486): @ dalvik.system.nativestart.main(native method) 05-18 17:37:16.301: i/process(486): sending signal. pid: 486 sig: 9

you have song_url defined inside try block hence not available outside.

so declare them before try :

public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.jsonview);      mp = new mediaplayer();     mp.setaudiostreamtype(audiomanager.stream_music);     play = (button) findviewbyid(r.id.play);     pause = (button) findviewbyid(r.id.pause);     next = (button) findviewbyid(r.id.next);     int current_song = 0;     string song_url[] = null;      try {     ....     ....     song_url = new string[list.length]; }