How to show only a specific region/area in google map for android api v2 [Android]

This trick worked for me

  @Override
public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;

    //get latlong for corners for specified place
    LatLng one = new LatLng(27.700769, 85.300140);
    LatLng two = new LatLng(27.800769, 85.400140);

    LatLngBounds.Builder builder = new LatLngBounds.Builder();

    //add them to builder
    builder.include(one);
    builder.include(two);

    LatLngBounds bounds = builder.build();

    //get width and height to current display screen
    int width = getResources().getDisplayMetrics().widthPixels;
    int height = getResources().getDisplayMetrics().heightPixels;

    // 20% padding
    int padding = (int) (width * 0.20);

    //set latlong bounds
    mMap.setLatLngBoundsForCameraTarget(bounds);

    //move camera to fill the bound to screen
    mMap.moveCamera(CameraUpdateFactory.newLatLngBounds(bounds, width, height, padding));

    //set zoom to level to current so that you won't be able to zoom out viz. move outside bounds
    mMap.setMinZoomPreference(mMap.getCameraPosition().zoom);
}