The getParent method returns a ViewParent, not a View. You need to cast the first call to getParent() also:
RelativeLayout r = (RelativeLayout) ((ViewGroup) this.getParent()).getParent();
As stated in the comments by the OP, this is causing a NPE. To debug, split this up into multiple parts:
ViewParent parent = this.getParent();
RelativeLayout r;
if (parent == null) {
Log.d("TEST", "this.getParent() is null");
}
else {
if (parent instanceof ViewGroup) {
ViewParent grandparent = ((ViewGroup) parent).getParent();
if (grandparent == null) {
Log.d("TEST", "((ViewGroup) this.getParent()).getParent() is null");
}
else {
if (parent instanceof RelativeLayout) {
r = (RelativeLayout) grandparent;
}
else {
Log.d("TEST", "((ViewGroup) this.getParent()).getParent() is not a RelativeLayout");
}
}
}
else {
Log.d("TEST", "this.getParent() is not a ViewGroup");
}
}
//now r is set to the desired RelativeLayout.