AlertDialog does not show dividers on a list

Question

I have this class:

public class PageDetailInfoView extends FrameLayout {

//few constructors and methods

//method to show an AlertDialog with a list
private void openDialog(){

    List<String> mTags = new ArrayList<String>();
    mTags.add("Item1");
    mTags.add("Item2");
    mTags.add("Item3");
    mTags.add("Item4");
    mTags.add("Item5");
    mTags.add("Item6");

    final CharSequence[] tags = mTags.toArray(new String[mTags.size()]);
    AlertDialog.Builder builder = new AlertDialog.Builder(getContext());
    builder.setTitle("Title");
    builder.setItems(tags, new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int item) {
        //do something
        }
    });

    Dialog alertDialogObject = builder.create();
    alertDialogObject.show();


}

The Alert dialog is opened after invoke openDialog() but the thing is that it does not exhibit the dividers between items. I would like to get this:
http://2.bp.blogspot.com/-i00d8VG6WsQ/UrGIeyb-8II/AAAAAAAAHwA/8MPWP5qrQ78/s500/alertdialog-with-simple-listview.png

and ,in fact, I get it but without the Gray dividers.
Any idea about why?

Answer 1

Change AlertDialog List items divider color as:

AlertDialog alertDialogObject = dialogBuilder.create();
ListView listView=alertDialogObject.getListView();  
listView.setDivider(new ColorDrawable(Color.BLUE)); // set color
listView.setDividerHeight(2); // set height 
alertDialogObject.show();