Question

how to give option to user to select camera in android.if user click button if front face is in preview .I have to show back camera.if back face is in preview .I have to show front face camera in android

Answer 1

This could help you :

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 the mirror
     } else {  // back-facing
         result = (info.orientation - degrees + 360) % 360;
     }
     camera.setDisplayOrientation(result);
 }

Also please refer to these links:

How do I open the "front camera" on the Android platform?

http://developer.android.com/reference/android/hardware/Camera.html