Highlight for selected item in expandable list

Question

I have a layout where I have an expandable list in a fragment on the left and a details fragment on the right. This all works fine.

Now I would like to indicate what

Answer 1

expListView.setOnChildClickListener(new OnChildClickListener() {

        @Override
        public boolean onChildClick( ExpandableListView parent, View v,
                                     int groupPosition, int childPosition,
                                     long id) {



            for (int i = 1; i < expListView.getChildCount(); i++) {
                View child = (View) expListView.getChildAt(i);
                child.setBackgroundColor(Color.BLACK);
            }


            if(childPosition==0){
                initWebView("URL");

            }
            if(childPosition==1) {
                initWebView("URL");

            }
            if(childPosition==2) {

                initWebView("URL");

            }
            if(childPosition==3) {
                initWebView("URL");

            }
            if(childPosition==4) {
                initWebView("URL");

            }
            if(childPosition==5) {
                initWebView("URL");
            }

            v.setBackgroundColor(Color.GRAY);


            expListView.setVisibility(View.GONE);
            webView.setVisibility(View.VISIBLE);
            return false;
        }
    });
}