Fragment is a view in android development. If you have gui elements which are repeating on different pages then you can use fragment. Android activity can be a collection of more than one fragments. Now in activity if you want to access any GUI element of fragment like Textview then you first need to get fragment and from fragment get that GUI element.
In first step give a tag to fragment in xml layout file
then in activity write following code
Fragment FragmentTopBar=getSupportFragmentManager().findFragmentByTag("tagtopfrg"); TextView txtCityname=FragmentTopBar.getView().findViewById(R.id.LblCityName); txtCityname.setText(citytext);
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