java - 导航栏中的底部按钮是什么，您有时会看到它用于更改设置

Question

那个黄色圆圈按钮如何调用以及如何让它显示？

Answer 1

这是传统的溢出按钮。这是必需的，以便旧应用程序可以在没有硬件菜单按钮的新设备上运行。

• If you set either minSdkVersion or targetSdkVersion to 11 or higher, the system will not add the legacy overflow button.

• Otherwise, the system will add the legacy overflow button when running on Android 3.0 or higher.

• The only exception is that if you set minSdkVersion to 10 or lower, set targetSdkVersion to 11, 12, or 13, and you do not use ActionBar, the system will add the legacy overflow button when running your app on a handset with Android 4.0 or higher.

http://android-developers.blogspot.com/2012/01/say-goodbye-to-menu-button.html

考虑设计您的应用，这样您就不需要遗留溢出。