static T of<T extends BlocBase>(BuildContext context) {
    final type = _typeOf<BlocProvider<T>>();
    BlocProvider<T> provider = context.ancestorWidgetOfExactType(type);
    return provider.bloc;
}

static T of<T extends BlocBase>(BuildContext context) {
    BlocProvider<T> provider = context.findAncestorWidgetOfExactType<BlocProvider<T>>();
    return provider.bloc;
}

<item name="android:windowDisablePreview">true</item>

screenOrientation=“portrait”

setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT); // 禁用横屏