React Native - 麻烦将父母的状态传递给孩子

Question

一个React新手，有一些问题从父组件传递状态和函数（本例中为App），并从子组件（在这种情况下为Main）访问。我确定这是一两个非常简单的错误，我在哪里被绊倒？

这是项目结构：

App
 |__ Rootstack
       |
       |__Favorites
       |__Main

以下是精简代码：

class Main extends React.Component {
  render() {
      return (
      <View>
         <Text>{this.props.favoritesList.length}</Text>
         <Card>
              onSwiped={() => {this.props.updateArray}} //the idea being that on a swipe, updateArray would add 1 to the 'favoriteList' in the parents state, and the favoritesList.length would update by +1.
         </Card>
      </View>
        );
    }
}

class Favorites extends React.Component {
          ....
    }

const RootStack = StackNavigator(
  {
    Main: {
      screen: Main},
    Favorites: {
      screen: Favorites}
  },
  {
    initialRouteName: 'Main'
  }
);


export default class App extends Component<{}> {
  constructor(props) {
      super(props);
      this.state = {
        favoritesList: []
      };
    this.updateArr = this.updateArr.bind(this); //don't know if this is necessary?
    }

  updateArr=()=>{this.setState({ favoritesList: 
      [...this.state.favoritesList, 'new value']})};

  render() {
      return <RootStack {...this.state} updateArray={this.updateArr}/>;
    }
  }

错误我得到的是 - 任何想法？提前谢谢！