camera - Take picture with headphones button -

i want take pictures camera when headphones button pressed.

but i'm getting runtime error saying "unable start receiver...takepicturefailed".

mi mainactivity:

public class mainactivity extends appcompatactivity{  protected static camera mycamera; private camerapreview mpreview; int icantcameras; int iactivecamera = 0; camera.parameters cpparameters; audiomanager am; static context context;  public static string appname;  private static final string tag = "mainactivity";  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_main);      appname = getstring(r.string.app_name_long);      context = getapplicationcontext();      // register , unregister receiver of headset button     = (audiomanager) this.getsystemservice(context.audio_service); }  @override protected void onresume(){     super.onresume();      // check if there's camera     if(!checkcamerahardware(this)){         toast.maketext(this, r.string.no_camera_message, toast.length_short).show();         return;     }      // start listening button presses     am.registermediabuttoneventreceiver(new componentname(this, receiver.class));      // number of cameras     icantcameras = camera.getnumberofcameras();      // activate camera     if (icantcameras > 0) {         activatecamera(iactivecamera);     } }  public static void takep(){     // image camera      mycamera.takepicture(null, null, mpicture);      //toast.maketext(context,"botón presionado", toast.length_short).show(); }  public void takephoto(view view){     // image camera     mycamera.takepicture(null, null, mpicture); }  public void showflashoptions(view view){  }  // change between cameras public void switchcamera(view view){     // return if there less 2 cameras     if (icantcameras < 2) {         return;     }      if (iactivecamera == camera.camerainfo.camera_facing_back) {         iactivecamera = camera.camerainfo.camera_facing_front;     } else {         iactivecamera = camera.camerainfo.camera_facing_back;     }      activatecamera(iactivecamera); }  // activate indicated camera public void activatecamera(int cameraid){      // instance of camera     releasecamera();      mycamera = getcamerainstance(cameraid);     if(mycamera == null){         toast.maketext(this, r.string.no_access_to_camera, toast.length_short).show();         return;     }      // camera parameters     cpparameters = mycamera.getparameters();      // set orientation of camera     setcameradisplayorientation(this, 0, mycamera);      // create our preview view , set content of our activity.     mpreview = new camerapreview(this, mycamera);     framelayout preview = (framelayout) findviewbyid(r.id.camera_preview);     preview.removeallviews(); // ensures switch of cameras calls mpreview.surfacechanged method     preview.addview(mpreview);  } /** check if device has camera */ private boolean checkcamerahardware(context context) {     if (context.getpackagemanager().hassystemfeature(packagemanager.feature_camera)){         // device has camera         return true;     } else {         // no camera on device         return false;     } }  /** safe way instance of camera object. */ public static camera getcamerainstance(int cameraid){     camera c = null;     try {         c = camera.open(cameraid); // attempt camera instance     }     catch (exception e){         // camera not available (in use or not exist)     }     return c; // returns null if camera unavailable }  // sets orientation of camera display public static void setcameradisplayorientation(activity activity,                                                int cameraid, android.hardware.camera camera) {     android.hardware.camera.camerainfo info =             new android.hardware.camera.camerainfo();     android.hardware.camera.getcamerainfo(cameraid, info);     int rotation = activity.getwindowmanager().getdefaultdisplay()             .getrotation();     int degrees = 0;     switch (rotation) {         case surface.rotation_0: degrees = 0; break;         case surface.rotation_90: degrees = 90; break;         case surface.rotation_180: degrees = 180; break;         case surface.rotation_270: degrees = 270; break;     }      int result;     if (info.facing == camera.camerainfo.camera_facing_front) {         result = (info.orientation + degrees) % 360;         result = (360 - result) % 360;  // compensate mirror     } else {  // back-facing         result = (info.orientation - degrees + 360) % 360;     }     camera.setdisplayorientation(result); }  // release camera other applications private void releasecamera(){     if (mycamera != null){         mycamera.stoppreview();         mycamera.setpreviewcallback(null);         mycamera.release();         mycamera = null;     } }  // saves picture storage public static camera.picturecallback mpicture = new camera.picturecallback() {      @override     public void onpicturetaken(byte[] data, camera camera) {         file picturefile = getoutputmediafile();         if (picturefile == null) {             log.d(tag, "error creating media file, check storage permissions");             return;         }          try {             fileoutputstream fos = new fileoutputstream(picturefile);             fos.write(data);             fos.close();         } catch (filenotfoundexception e) {             log.d(tag, "file not found: " + e.getmessage());         } catch (ioexception e) {             log.d(tag, "error accessing file: " + e.getmessage());         }          // gets picture media library         mediascanner client = new mediascanner(context, picturefile, null);     } };  /** create file saving image */ private static file getoutputmediafile(){     // safe, should check sdcard mounted     // using environment.getexternalstoragestate() before doing this.      file mediastoragedir = new file(environment.getexternalstoragepublicdirectory(             environment.directory_pictures), appname);      // create storage directory if not exist     if (! mediastoragedir.exists()){         if (! mediastoragedir.mkdirs()){             log.d(appname, "failed create directory");             return null;         }     }      // create media file name     string timestamp = new simpledateformat("yyyymmdd_hhmmss").format(new date());     file mediafile;     mediafile = new file(mediastoragedir.getpath() + file.separator +                 "img_"+ timestamp + ".jpg");      return mediafile; }  @override protected void onstop(){     super.onstop();     releasecamera();     // stop listening button presses     am.unregistermediabuttoneventreceiver(new componentname(this, receiver.class)); }  @override protected void ondestroy(){     super.ondestroy();     releasecamera();     // stop listening button presses     am.unregistermediabuttoneventreceiver(new componentname(this, receiver.class)); } 

}

my preview class:

public class camerapreview extends surfaceview implements surfaceholder.callback { private surfaceholder mholder; private camera mcamera;  public camerapreview(context context, camera camera) {     super(context);     mcamera = camera;      // install surfaceholder.callback notified when     // underlying surface created , destroyed.     mholder = getholder();     mholder.addcallback(this);     // deprecated setting, required on android versions prior 3.0     mholder.settype(surfaceholder.surface_type_push_buffers); }  public void surfacecreated(surfaceholder holder) {     // surface has been created, tell camera draw preview.     try {         mcamera.setpreviewdisplay(holder);         mcamera.startpreview();     } catch (ioexception e) {         log.d("tag", "error setting camera preview: " + e.getmessage());     } }  public void surfacedestroyed(surfaceholder holder) {     // empty. take care of releasing camera preview in activity. }  public void surfacechanged(surfaceholder holder, int format, int w, int h) {     // if preview can change or rotate, take care of events here.     // make sure stop preview before resizing or reformatting it.      if (mholder.getsurface() == null){         // preview surface not exist         return;     }      // stop preview before making changes     try {         mcamera.stoppreview();     } catch (exception e){         // ignore: tried stop non-existent preview     }      // set preview size , make resize, rotate or     // reformatting changes here      // start preview new settings     try {         mcamera.setpreviewdisplay(mholder);         mcamera.startpreview();      } catch (exception e){         log.d("tag", "error starting camera preview: " + e.getmessage());     } } 

}

my receiver class, call takep() method of mainactivity class:

public class receiver extends broadcastreceiver { // constructor mandatory public receiver () {     super (); }  @override public void onreceive(context context, intent intent) {      if (intent.action_media_button.equals(intent.getaction())) {         keyevent event = (keyevent)intent.getparcelableextra(intent.extra_key_event);         int key = event.getkeycode();         switch (key) {             case keyevent.keycode_break:             case keyevent.keycode_media_play:             case keyevent.keycode_media_play_pause:             case keyevent.keycode_media_stop:             case keyevent.keycode_headsethook:                 mainactivity.takep();                 break;             default:                 break;         }      } } 

}

my logical:

10-30 20:10:43.257 28252-28252/? e/androidruntime: fatal exception: main 10-30 20:10:43.257 28252-28252/? e/androidruntime: process: com.garanal.photoclick, pid: 28252 10-30 20:10:43.257 28252-28252/? e/androidruntime: java.lang.runtimeexception: unable start receiver com.garanal.photoclick.receiver: java.lang.runtimeexception: takepicture failed 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.app.activitythread.handlereceiver(activitythread.java:2680) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.app.activitythread.access$1700(activitythread.java:156) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.app.activitythread$h.handlemessage(activitythread.java:1428) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.os.handler.dispatchmessage(handler.java:102) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.os.looper.loop(looper.java:211) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.app.activitythread.main(activitythread.java:5389) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ java.lang.reflect.method.invoke(native method) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ java.lang.reflect.method.invoke(method.java:372) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:1020) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ com.android.internal.os.zygoteinit.main(zygoteinit.java:815) 10-30 20:10:43.257 28252-28252/? e/androidruntime:  caused by: java.lang.runtimeexception: takepicture failed 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.hardware.camera.native_takepicture(native method) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.hardware.camera.takepicture(camera.java:1475) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.hardware.camera.takepicture(camera.java:1420) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ com.garanal.photoclick.mainactivity.takep(mainactivity.java:82) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ com.garanal.photoclick.receiver.onreceive(receiver.java:33) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.app.activitythread.handlereceiver(activitythread.java:2673) 10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.app.activitythread.access$1700(activitythread.java:156)  10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.app.activitythread$h.handlemessage(activitythread.java:1428)  10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.os.handler.dispatchmessage(handler.java:102)  10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.os.looper.loop(looper.java:211)  10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ android.app.activitythread.main(activitythread.java:5389)  10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ java.lang.reflect.method.invoke(native method)  10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ java.lang.reflect.method.invoke(method.java:372)  10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:1020)  10-30 20:10:43.257 28252-28252/? e/androidruntime:     @ com.android.internal.os.zygoteinit.main(zygoteinit.java:815)  

thank can give me , greetings medellin, colombia.