My simple camera app (android) won't load the camera view after the first attempt -

i'm trying make simple camera app uses runtime permissions...it seems load fine first time app launched (asking camera permission). after allowing access, works...but close , start again, shows white image icons won't respond. i've checked permissions manually in app , camera still granted access think i'm screwing permissions code.

here mainactivity code:

public class mainactivity extends appcompatactivity {      private static final int my_permissions_request_camera = 1;     private camera mcamera = null;     private camera mcamerafront = null;     private cameraview mcameraview = null;     public int switchcamera = 1;   //    int permissioncheck = contextcompat.checkselfpermission(this, //            manifest.permission.camera);  //    string[] perms = {"android.permission.camera"};   //    int permsrequestcode = 200;      protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.main);          if (contextcompat.checkselfpermission(this,                 manifest.permission.camera)                 != packagemanager.permission_granted) {              // should show explanation?             if (activitycompat.shouldshowrequestpermissionrationale(this,                     manifest.permission.camera)) {                  // show explanation user *asynchronously* -- don't block                 // thread waiting user's response! after user                 // sees explanation, try again request permission.              } else {                  // no explanation needed, can request permission.                  activitycompat.requestpermissions(this,                         new string[]{manifest.permission.camera},                         my_permissions_request_camera);                  try {                     mcamera = camera.open(1);//you can use open(int) use different cameras                 } catch (exception e) {                     log.d("error", "failed camera: " + e.getmessage());                 }                 swapcamera();  //                if (mcamera != null) { ////                        mcameraview = new cameraview(this, mcamera);//create surfaceview show camera data ////                        framelayout camera_view = (framelayout)findviewbyid(r.id.camera_view); ////                        camera_view.addview(mcameraview);//add surfaceview layout //                    swapcamera(); //                }                  //btn close application                 imagebutton imgclose = (imagebutton) findviewbyid(r.id.imgclose);                 imgclose.setonclicklistener(new view.onclicklistener() {                     @override                     public void onclick(view view) {                         mcamera.setpreviewcallback(null);                         mcamera.seterrorcallback(null);                         mcamera.stoppreview();                         mcamera.release();                         mcamera = null;                         system.exit(0);                     }                 });  //                     btn switch camera                 imagebutton imgswitch = (imagebutton) findviewbyid(r.id.cameraswitch);                 imgswitch.setonclicklistener(new view.onclicklistener() {                     @override                     public void onclick(view view) { //                            switchcamera++;                     }                 });               }         }     }        public void swapcamera() {         mcameraview = new cameraview(this, mcamera);//create surfaceview show camera data         framelayout camera_view = (framelayout)findviewbyid(r.id.camera_view);         camera_view.addview(mcameraview);//add surfaceview layout     }      @override     public void onrequestpermissionsresult(int requestcode,                                            string permissions[], int[] grantresults) {          switch (requestcode) {             case my_permissions_request_camera: {                 // if request cancelled, result arrays empty.                 if (grantresults.length > 0                         && grantresults[0] == packagemanager.permission_granted) {                        // permission granted, yay!                     // camera-related task need do.                      try{                         mcamera = camera.open(1);//you can use open(int) use different cameras                     } catch (exception e){                         log.d("error", "failed camera: " + e.getmessage());                     }                      if(mcamera != null) { //                        mcameraview = new cameraview(this, mcamera);//create surfaceview show camera data //                        framelayout camera_view = (framelayout)findviewbyid(r.id.camera_view); //                        camera_view.addview(mcameraview);//add surfaceview layout                         swapcamera();                     }                      //btn close application                     imagebutton imgclose = (imagebutton)findviewbyid(r.id.imgclose);                     imgclose.setonclicklistener(new view.onclicklistener() {                         @override                         public void onclick(view view) {                             mcamera.setpreviewcallback(null);                             mcamera.seterrorcallback(null);                             mcamera.stoppreview();                             mcamera.release();                             mcamera = null;                             system.exit(0);                         }                     });  //                     btn switch camera                     imagebutton imgswitch = (imagebutton)findviewbyid(r.id.cameraswitch);                     imgswitch.setonclicklistener(new view.onclicklistener() {                         @override                         public void onclick(view view) { //                            switchcamera++;                        }                     });                    } else {                      // permission denied, boo! disable                     // functionality depends on permission.                 }                 return;             }              // other 'case' lines check other             // permissions app might request         }     }      public void onactivityresult() {      }   } 

i believe missing "else"

if (contextcompat.checkselfpermission(this,                 manifest.permission.camera)                 != packagemanager.permission_granted) { // code  } else {    // stuff camera    try{       mcamera = camera.open(1);    } catch (exception e){    ... }