<fragment
   android:id="@+id/mapFragment"
   android:name="com.google.android.gms.maps.SupportMapFragment"
   android:layout_height="@dimen/_200sdp" />

SupportMapFragment supportMapFragment = ((SupportMapFragment) getSupportFragmentManager()
            .findFragmentById(R.id.mapFragment));
supportMapFragment.getMapAsync(this);