Use the ContentResolver to return the Uri to a new blank external content URI location, and provide a blank ContentValues metadata object

Uri imageFileUri = getContentResolver().insert( 
  new ContentValues()

Start the Camera Activity using an Intent

Intent i = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);

tell the intent where to store the Image using the MediaStore provided URI

i.putExtra(android.provider.MediaStore.EXTRA_OUTPUT, imageFileUri);

Start the Activity and tell the Intent that we are interested in the result of its actions:

startActivityForResult(i, CAMERA_RESULT);