Introduction - If you have any usage issues, please Google them yourself
Write an application, with " computing" menu that contains the menu item " Show Dialog" and " Exit." Click the " Show Dialog" option, pop-up " modal dialog" This dialog box contains two horizontal scroll bar four buttons, namely " plus" , " minus" , " ride" , " except" three edit boxes, click on any one of the four buttons in the calculation operation, move the scroll bar, two edit boxes appear scroll position, another edit box appears calculations.