问题:

My application is written in delphi. For some reason the main menu does not behave anymore like it did until yesterday (I probably touched some property without knowing). Now when I click on a menu item with sub-items, though the arrow is located to the right, the submenu keeps opening to the left.

What is the reason and how do I restore it back?

回答1:

As revealed in the comments to the question, this is not programming related. There's a setting that does this in tablet pc settings in control panel. The reason for the setting is, when one is using a pen or the like with the right hand, sub menus, if opened to the right of their parent menu, are obscured by the pen.

回答2:

I had the same problem and it had nothing to do with my "touch screen" or other pc tablet related settings I found out by changing some features of the MainMenu of type TMainMenu: Just set the "OwnerDraw" feature to False and "ParentBiDiMode" to true So if your parent view is already fine this MainMenu (submenu) will conform to its parent. I did it 100s of times and it worked for me