How to change camera from front to back and back to front on button click in android -

i working on android tablet application. want change camera front , front on button. how can achieve ? have tried several example not getting proper response.

i adding code also.

public class photopreview extends activity implements surfaceholder.callback {  private camera camera; private imagebutton cameraclick; private imagebutton cameraswap; surfaceview surfaceview; private surfaceholder mholder; boolean previewing = false; string path = ""; layoutinflater controlinflater = null; bitmap bmp; button cameracancel; private sharedpreferences myprefs; private int camid;  /** called when activity first created. */ @suppresswarnings("deprecation") @override public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);      system.out.println("photo preview called $$$$$$$$$$$$$$$$$$ ");      requestwindowfeature(window.feature_no_title);     getwindow().setflags(windowmanager.layoutparams.flag_fullscreen,             windowmanager.layoutparams.flag_fullscreen);     setcontentview(r.layout.photo_preview);      myprefs = this.getsharedpreferences("myprefs", mode_private);     camid = myprefs.getint("camid",1);      system.out.println("cam id $$$$$$$$$$$$$$$$$$ "+camid);      getwindow().setformat(pixelformat.unknown);     surfaceview = (surfaceview) findviewbyid(r.id.camerapreview);      mholder = surfaceview.getholder();     mholder.settype(surfaceholder.surface_type_push_buffers);     mholder.addcallback(this);       controlinflater = layoutinflater.from(getbasecontext());     view viewcontrol = controlinflater.inflate(r.layout.control, null);     layoutparams layoutparamscontrol = new layoutparams(             layoutparams.match_parent, layoutparams.match_parent);     this.addcontentview(viewcontrol, layoutparamscontrol);     cameraclick = (imagebutton) findviewbyid(r.id.cameraclick);     cameraclick.setonclicklistener(cameraclicklistener);     cameracancel = (button) findviewbyid(r.id.cameracancel);     cameracancel.setonclicklistener(cameracancelclicklistener);     cameraswap = (imagebutton) findviewbyid(r.id.cameraswap);     cameraswap.setonclicklistener(swapcameraclicklistener);  }  /*  * click event of photo capture button  */ private onclicklistener cameraclicklistener = new onclicklistener() {     @override     public void onclick(final view v) {         if (camera != null) {             camera.takepicture(shuttercallback, rawcallback, jpegcallback);         }      } };  /*  * click event of camera cancel button  */ private onclicklistener cameracancelclicklistener = new onclicklistener() {     @override     public void onclick(final view v) {          intent intent = new intent(photopreview.this,                 mainscreenactivity.class);         startactivity(intent);      } };  /*  * click event of camera cancel button  */ private onclicklistener swapcameraclicklistener = new onclicklistener() {     @override     public void onclick(final view v) {          if (camid == 0) {             sharedpreferences.editor prefseditor = myprefs.edit();             prefseditor.putint("camid", 1);             prefseditor.commit();          } else {             sharedpreferences.editor prefseditor = myprefs.edit();             prefseditor.putint("camid", 0);             prefseditor.commit();         }         system.out.println("cam id ^^^^^^^^^^^^^^^^^^^^ "+camid);         intent intent = new intent(photopreview.this, photopreview.class);         startactivity(intent);      } };  // handles when shutter open shuttercallback shuttercallback = new shuttercallback() {     public void onshutter() {      } };  /** handles data raw picture */ picturecallback rawcallback = new picturecallback() {     public void onpicturetaken(byte[] data, camera camera) {      } };  /** handles data jpeg picture */ picturecallback jpegcallback = new picturecallback() {     public void onpicturetaken(byte[] data, camera camera) {         bmp = bitmapfactory.decodebytearray(data, 0, data.length);          string root = environment.getexternalstoragedirectory().tostring();         file mydir = new file(root + "/easy_measurement_images");         mydir.mkdirs();         random generator = new random();         int n = 10000;         n = generator.nextint(n);         string fname = "image-" + n + ".jpg";         file file = new file(mydir, fname);         if (file.exists())             file.delete();         try {             fileoutputstream out = new fileoutputstream(file);             bmp.compress(bitmap.compressformat.png, 90, out);             out.flush();             out.close();          } catch (exception e) {             e.printstacktrace();         }          intent intent = new intent(photopreview.this,                 verticaladjustmentactivity.class);         startactivity(intent);     } };  @override public void surfacechanged(surfaceholder holder, int format, int width,         int height) {      // set camera preview size,orientation,rotation using parameters     if (camera != null) {         camera.parameters parameters = camera.getparameters();         parameters.set("orientation", "portrait");         camera.setparameters(parameters);         camera.startpreview();     }  }  @override public void surfacecreated(surfaceholder holder) {      system.out.println("cam id %%%%%%%%%%%%%%$$$$$$$$$$$$$$$$$$ "+camid);     camera = camera.open(camid);      if (camera != null) {         try {             camera.setpreviewdisplay(holder);         } catch (ioexception e) {             e.printstacktrace();         }     }  }  @override public void surfacedestroyed(surfaceholder holder) {      system.out.println("surface destroyed ***************");     if (camera != null) {         camera.stoppreview();         camera.release();         camera = null;     }  } 

}

you can open camera using camera.open(int i). can use 1 camera @ time. release 1 , open another. example

public void onclick(view v) {  camera.stoppreview();  camera.release();   if(currentcameraid == camera.camerainfo.camera_facing_back){     currentcameraid = camera.camerainfo.camera_facing_front; } else {     currentcameraid = camera.camerainfo.camera_facing_back; }  camera = camera.open(currentcameraid);  setcameradisplayorientation(cameraactivity.this, currentcameraid, camera); try {     camera.setpreviewdisplay(previewholder); } catch (ioexception e) {     e.printstacktrace(); } camera.startpreview(); 

}