完成AS创建活动后,我发现默认情况下MainActivity正在扩展AppCompatActivity.
我读到了AppCompatActivity here
它表示它是使用support library操作栏功能的活动的Base类.
现在我的问题是：
>由于我的应用程序的minSdkVersion为21,为什么我需要我的活动来扩展AppCompatActivity？
>为什么AS使我的活动默认扩展AppCompatActivity？
>考虑到我的minSdkVerion,我的活动是否有必要扩展AppCompatActivity或只是扩展Activity就足够了？
>如果我的行为不扩展AppCompatActivity,我会想念什么？
任何解释都会非常有用.谢谢
解决方法
Beginning with Android 3.0 (API level 11),all activities that use the default theme have an ActionBar as an app bar. However,app bar features have gradually been added to the native ActionBar over varIoUs Android releases. As a result,the native ActionBar behaves differently depending on what version of the Android system a device may be using. By contrast,the most recent features are added to the support library’s version of Toolbar,and they are available on any device that can use the support library.
For this reason,you should use the support library’s Toolbar class to implement your activities’ app bars. Using the support library’s toolbar helps ensure that your app will have consistent behavior across the widest range of devices. For example,the Toolbar widget provides a material design experience on devices running Android 2.1 (API level 7) or later,but the native action bar doesn’t support material design unless the device is running Android 5.0 (API level 21) or later.