哪里可以使用onSaveInstanceState,其中参数传递的是不同的Activity？

Question

对于Acitivity,已经存在一个名为onSaveInstacestate(Bundle)的方法,该方法用于存储被覆盖方法的活动数据.

正如我所看到的,有两个不同的onSaveInstanceState,其中参数的传递方式如下所示.

@Override
    public void onSaveInstanceState(Bundle outState, PersistableBundle outPersistentState)
    {
        super.onSaveInstanceState(outState, outPersistentState);
        Log.i("test", "onSaveInstanceState called **********");
    }

和

@Override
    protected void onSaveInstanceState(Bundle outState)
    {
         super.onSaveInstanceState(outState);
          Log.i("test", "onSaveInstanceState with bundle only called");
    }

那么,在什么情况下这两种方法都可以使用？请详细说明.提前致谢.

Answer 1

这值得一个扩展的答案。如公认的答案所述，由于API级别21的存在一个额外的重载onSaveInstanteState。

自API级别1（Docs）起可用：

void onSaveInstanceState (Bundle outState)

API级别21（Docs）引入的附加功能：

void onSaveInstanceState (Bundle outState, PersistableBundle outPersistentState)

带有的后者PersistableBundle不能替代前者。仅在Activity属性R.attr.persistableMode设置为as时使用persistAcrossReboots。当这样的Activity持久化onSaveInstanceState (Bundle outState, PersistableBundle outPersistentState)将被调用时，您会收到一个PersistableBundle存储实例状态的信息。

要恢复的状态Activity与R.attr.persistableMode设定为persistAcrossReboots，有

void onRestoreInstanceState (Bundle savedInstanceState, PersistableBundle persistentState)

请注意，onRestoreInstanceState (Bundle savedInstanceState)如果调用了，则不会PersistableBundle调用。我假设的情况也是如此onSaveInstanceState，但我尚未检查它，并且在API级别28时文档未提及它。

还有一个适当的重载onCreate()。

Answer 2

从API Level 21开始,onSaveInstanceState()有一个名为take的对象的新参数PersistableBundle.您可以在Docs上阅读有关PersistableBundle的更多信息

简而言之,

适用于API 21及更高版本

@Override
    public void onSaveInstanceState(Bundle outState, PersistableBundle outPersistentState)
    {
        super.onSaveInstanceState(outState, outPersistentState);
        Log.i("test", "onSaveInstanceState called **********");
    }

对于API小于20

@Override
    protected void onSaveInstanceState(Bundle outState)
    {
         super.onSaveInstanceState(outState);
          Log.i("test", "onSaveInstanceState with bundle only called");
    }