Question

当我使用Stack导航时，组件会“刷新”，它会正确执行useEffect动作；如果使用Drawer导航，它只会更新一次，则离开一个屏幕，然后进入另一个屏幕，然后返回第一个屏幕， useEffect不会再次执行，如果Stack导航可以完美执行。有人可以指导我吗？

我不会说英语，对不起我的写作

Answer 1

这是因为您需要在带有“ focus”事件的效果挂钩中使用navigation.addListener订阅才能收听。

https://reactnavigation.org/docs/navigation-events/#navigationaddlistener

这是一个App.js独立演示（从一个空白的expo init项目开始）：

import React from "react";
import { StyleSheet, Text, View } from "react-native";
import { createDrawerNavigator } from "@react-navigation/drawer";
import { NavigationContainer } from "@react-navigation/native";

const Drawer = createDrawerNavigator();

function MyDrawer() {
  return (
    <Drawer.Navigator>
      <Drawer.Screen name="Feed" component={Feed} />
      <Drawer.Screen name="Article" component={Article} />
    </Drawer.Navigator>
  );
}

function Feed({ navigation }) {
  React.useEffect(() => {
    const unsubscribe = navigation.addListener("focus", () => {
      // do something
      console.log("feed is focused");
    });

    return unsubscribe;
  }, [navigation]);

  return (
    <View style={styles.container}>
      <Text>Feed</Text>
    </View>
  );
}

function Article({ navigation }) {
  React.useEffect(() => {
    const unsubscribe = navigation.addListener("focus", () => {
      // do something
      console.log("article is focused");
    });

    return unsubscribe;
  }, [navigation]);

  return (
    <View style={styles.container}>
      <Text>Article</Text>
    </View>
  );
}

export default function App() {
  return (
    <NavigationContainer>
      <MyDrawer />
    </NavigationContainer>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: "#fff",
    alignItems: "center",
    justifyContent: "center",
  },
});

抽屉导航不会像堆栈导航那样更新组件

1 个答案: