I created the AlertDialog using the builder. It shows when we call the show() method. I have the cancel button in that dialog. I can cance
This is happening because you are trying to re-use the dialog which was already created (Probably at onCreate)and used once. There is no issue in reusing a dialog but as in the question the the specified child (the view) already has a parent (the dialog).You could either continue by removing the parent or you can create a new parent like :-
alertDialog=new AlertDialog(Context);
alertDialog.setView(yourView);
alertDialog.show();