Fly-out Menu - Interaction Design Pattern Library - Welie.com

• difficult to select if you leave the area. Make it wider that it appears so that it doesn't disappear if you are moving the mouse just a couple of pixels outside of the menu'
• Fly-out with submenus are not a good idea. Really hard to select (Fitts law)
• You must make it clear that it is a menu, for example by adding a down-pointing triangle next to the label
• Make sure they work without Javascript for accessibility reasons. Otherwise search engines cannot index your site and accessibility also suffers.
• Use a delay before hiding the fly-out menu again, e.g. 250ms
• Only use horizontal menus with vertical fly-out menus. The vertical area in which the mouse-pointer needs to be move is too small, i.e. typically 12-14px, and causes the menu to be hidden unwantedly

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