i need to have the menu button shown for some activities on galaxy nexus . i can't find how to do that, since it hides it by default . i don't wish to create an action bar since it takes more space that i want to use to other things . when setting the "android:targetSdkVersion" value to lower than 14 , it seems to show the menu button , but otherwise, it hides it . btw, the activity needs to be full screen , with no title/action bars .
it is very weird that this button is not shown by default for so many places (even the launcher) , and on some places it does exist . such a button is a very basic one for so many android devices . google decided that not only that , but instead , the switching button is more important to be shown and it's shown by default (no idea if it's possible to hide it, but i guess not , since home button no longer does anything when long pressed) .
anyway, please help me . i'm quite new on android 4 .
The Menu button has been deprecated in ICS. Your options are 1) run in legacy mode (targetSdkVersion < 14), 2) use an action bar with or without an overflow menu button, 3) add a menu button somewhere in your app area. 4) not using a menu and just adding its actions directly to your app area.
The menu button is more of a legacy thing on newer Android phones with bigger screens since it's normally best to use the Action Bar (1) to provide the user with the actions that would normally be on the menu. These are called "Action Items" and are a better user experience because they appear directly on the Action Bar rather than requiring the user to tap the menu button.
(1) http://developer.android.com/guide/topics/ui/actionbar.html
来源：https://stackoverflow.com/questions/8897763/android-show-menu-button-on-galaxy-nexus