Flutter plugin 如何在插件中获取FragmentA

插件类继承 ActivityAware，重写onAttachedToActivity、onDetachedFromActivityForConfigChanges、onReattachedToActivityForConfigChanges、onDetachedFromActivity四个方法，其中在onAttachedToActivity、onReattachedToActivityForConfigChanges可以获取到getActivity

public class MyFfPlugin implements FlutterPlugin, MethodCallHandler, ActivityAware {}

@Override
  public void onAttachedToActivity(@NonNull ActivityPluginBinding binding) {
     activity =  binding.getActivity();
  }

那么如何获取FragmentActivity呢？现在很多插件库都是需要用到FragmentActivity，如果传入activity 是不行的
答案：找到 MainActivity

image.png

public class MainActivity extends FlutterActivity {

}

这里的FlutterActivity 显然是继承了Activity，所以你在插件onAttachedToActivity中拿到的就是Activity

image.png

如果你想拿到FragmentActivity，MainActivity就不能继承FlutterActivity ，而是继承FlutterFragmentActivity
修改后

import io.flutter.embedding.android.FlutterFragmentActivity;
public class MainActivity extends FlutterFragmentActivity {

}

然后回到插件类中,把fragmentActivity 保存到顶部，方便其他方法使用

  @Override
  public void onAttachedToActivity(@NonNull ActivityPluginBinding binding) {
    if (binding.getActivity() instanceof FragmentActivity) {
      fragmentActivity = (FragmentActivity) binding.getActivity();
    }
  }