hiding menu on click

I am using NullField() in one of my screen so that the default focus should not b开发者_Python百科e on any of the button . but when i am clicking on the screen where no field is there , menu screen is being displayed. i dont want that menu screen to be poped up tough it should open when i click menu button.

Thanks alot

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override method.

protected boolean navigationClick(int status, int time) {
            Field focus = UiApplication.getUiApplication().getActiveScreen()
                    .getLeafFieldWithFocus();
            if (focus instanceof NullField) {
                return true;
            }
            return super.navigationClick(status, time);
        }

Note:This code is only for giving you hint.