Remove incorrect usage of AlertDialog.Builder.create

AlertDialog.Builder.show() will create an AlertDialog before it show. This is the source code snippet:

        /**
         * Creates a {@link AlertDialog} with the arguments supplied to this builder and
         * {@link Dialog#show()}'s the dialog.
         */
        public AlertDialog show() {
            AlertDialog dialog = create();
            dialog.show();
            return dialog;
        }

github: close #96