undefined不是一個物件（評估'navigation.navigate'）（設備）-有解無憂

const Home = ({navigation}) => {
  
  const renderDiscoverItem = ({item}) => {
    return (
      <TouchableOpacity
        onPress={() =>
         navigation.navigate('Details', {
            item: item,
          })
        }>
        <ImageBackground
          source={item.images}
          style={[
            styles.discoverItem,
            {marginLeft: item.id === 'discover-1' ? 20 : 0},
          ]}
          imageStyle={styles.discoverItemImage}>
          <Text style={styles.discoverItemTitle}>{item.title}</Text>
          <View style={styles.discoverItemLocationWrapper}>
            <Entypo name="location-pin" size={18} color={colors.white} />
            <Text style={styles.discoverItemLocationText}>{item.location}</Text>
          </View>
        </ImageBackground>
      </TouchableOpacity>
    );
  };

uj5u.com熱心網友回復：

有2個問題，

您在 App.js 中直接匯出 Home，這意味著 Home 沒有包含在任何導航器中，請在下面找到 App.js 的更正代碼

import React from 'react';
import { View, Text, StyleSheet } from 'react-native';
import Home from './components/Home';
import Details from './components/Details';
import Liked from './components/Liked';
import Profile from './components/Profile';
import colors from './assets/colors/colors';
import Entypo from 'react-native-vector-icons/Entypo';
import MaterialCommunityIcons from 'react-native-vector-icons/MaterialCommunityIcons';

import {NavigationContainer} from '@react-navigation/native';
import {createStackNavigator} from '@react-navigation/stack';
import {createBottomTabNavigator} from '@react-navigation/bottom-tabs';

Entypo.loadFont();
MaterialCommunityIcons.loadFont();

const Stack = createStackNavigator();
const Tab = createBottomTabNavigator();

const TabNavigator = () => {
  return (
    <Tab.Navigator
      tabBarOptions={{
        style: styles.tabBar,
        activeTintColor: colors.orange,
        inactiveTintColor: colors.gray,
        showLable: false,
      }}>
      <Tab.Screen
        name="Home"
        component={Home}
        options={{
          tabBarIcon: ({color}) => (
            <Entypo name="home" size={32} color={color} />
          ),
        }}
      />
      <Tab.Screen
        name="Liked"
        component={Liked}
        options={{
          tabBarIcon: ({color}) => (
            <Entypo name="heart" size={32} color={color} />
          ),
        }}
      />
      <Tab.Screen 
      name="Profile" 
      component={Profile} 
      options={{
        tabBarIcon: ({color}) => (
          <MaterialCommunityIcons name="account" size={32} color={color} />
        ),
      }}
      />
    </Tab.Navigator>
  );
};


const App = () => {
  console.log('inside app')
  return (
    <NavigationContainer>
      <Stack.Navigator>
        <Stack.Screen  
        name="TabNavigator" 
        component={TabNavigator} 
        options={{headerShown: false}} 
        />
       <Stack.Screen 
        name="Details" 
        component={Details} 
        options={{headerShown: false}} 
        />
      </Stack.Navigator>
    </NavigationContainer>
  );
};

const styles = StyleSheet.create({
  tabBar: {
    backgroundColor: colors.white,
    borderTapLeftRedius: 20,
    borderTopRightRadius: 20,
  },
});

export default App;

第二個錯誤是useNavigation鉤子的用法，它必須在更正的代碼中如下使用，

import React from 'react';
import {
  View,
  Text,
  StyleSheet,
  Image,
  ScrollView,
  ImageBackground,
  AppRegistry,
} from 'react-native';
import colors from '../assets/colors/colors';
import Feather from 'react-native-vector-icons/Feather';
import Entypo from 'react-native-vector-icons/Entypo';
import activitiesData from '../assets/data/activitiesData';
import discoverCategoriesData from '../assets/data/discoverCategoriesData';
import learnMoreData from '../assets/data/learnMoreData';
import discoverData from '../assets/data/discoverData';
import {SafeAreaView} from 'react-native-safe-area-context';
import profile from '../assets/images/profile.png';
import {FlatList, TouchableOpacity} from 'react-native-gesture-handler';
import { useNavigation } from '@react-navigation/native';



Feather.loadFont();
Entypo.loadFont();

 

const Home = () => {
  const navigation = useNavigation();
  
  const renderDiscoverItem = ({item}) => {
    return (
      <TouchableOpacity
        onPress={() =>
         navigation.navigate('Details', {
            item: item,
          })
        }>
        <ImageBackground
          source={item.images}
          style={[
            styles.discoverItem,
            {marginLeft: item.id === 'discover-1' ? 20 : 0},
          ]}
          imageStyle={styles.discoverItemImage}>
          <Text style={styles.discoverItemTitle}>{item.title}</Text>
          <View style={styles.discoverItemLocationWrapper}>
            <Entypo name="location-pin" size={18} color={colors.white} />
            <Text style={styles.discoverItemLocationText}>{item.location}</Text>
          </View>
        </ImageBackground>
      </TouchableOpacity>
    );
  };

  const renderActivityItem = ({item}) => {
    return (
      <View
        style={[
          styles.activityItemWrapper,
          {
            marginLeft: item.id === 'activities-1' ? 20 : 0,
          },
        ]}>
        <Image source={item.image} style={styles.activityItemImage} />
        <Text style={styles.activityItemText}>{item.title}</Text>
      </View>
    );
  };

  const renderLearnMoreItem = ({item}) => {
    return (
      <ImageBackground
        source={item.images}
        style={[
          styles.learnMoreItem,
          {
            marginLeft: item.id === 'learnMore-1' ? 20 : 0,
          },
        ]}
        imageStyle={styles.learnMoreItemImage}>
        <Text style={styles.learnMoreItemText}>{item.title}</Text>
      </ImageBackground>
    );
  };

  return (
    <View style={styles.container}>
      <ScrollView>
        {/* Header */}
        <SafeAreaView>
          <View style={styles.menuWrapper}>
            <Feather
              name="menu"
              size={32}
              color={colors.black}
              style={styles.menuIcon}
            />
            <Image source={profile} style={styles.profileImage} />
          </View>
        </SafeAreaView>

        {/* Discover */}
        <View style={styles.discoverWrapper}>
          <Text style={styles.discoverTitle}>Discover</Text>
          <View style={styles.discoverCategoriesWrapper}>
            <Text style={[styles.discoverCategoryText, {color: colors.orange}]}>
              All
            </Text>
            <Text style={styles.discoverCategoryText}>Destinations</Text>
            <Text style={styles.discoverCategoryText}>Cities</Text>
            <Text style={styles.discoverCategoryText}>Experiences</Text>
          </View>
          <View style={styles.discoverItemsWrapper}>
            <FlatList
              data={discoverData}
              renderItem={renderDiscoverItem}
              keyExtractor={(item) => item.id}
              horizontal
              showsHorizontalScrollIndicator={false}
            />
          </View>
        </View>

        {/* Activities */}
        <View style={styles.activitiesWrapper}>
          <Text style={styles.activitiesTitle}>Activities</Text>
          <View style={styles.activitiesItemsWrapper}>
            <FlatList
              data={activitiesData}
              renderItem={renderActivityItem}
              keyExtractor={(item) => item.id}
              horizontal
              showsHorizontalScrollIndicator={false}
            />
          </View>
        </View>

        {/* Learn More */}
        <View style={styles.learnMoreWrapper}>
          <Text style={styles.learnMoreTitle}>Learn More</Text>
          <View style={styles.learnMoreItemsWrapper}>
            <FlatList
              data={learnMoreData}
              renderItem={renderLearnMoreItem}
              keyExtractor={(item) => item.id}
              horizontal
              showsHorizontalScrollIndicator={false}
            />
          </View>
        </View>
      </ScrollView>
    </View>
  );
};

const styles = StyleSheet.create({
  container: {
    flex: 1,
    color: colors.white,
  },
  menuWrapper: {
    marginHorizontal: 20,
    marginTop: 20,
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignItems: 'center',
  },
  profileImage: {
    width: 52,
    height: 52,
    borderRadius: 10,
  },
  discoverWrapper: {
    // marginHorizontal: 20,
    marginTop: 20,
  },
  discoverTitle: {
    marginHorizontal: 20,
    fontFamily: 'Lato-Bold',
    fontSize: 32,
  },
  discoverCategoriesWrapper: {
    marginHorizontal: 20,
    flexDirection: 'row',
    marginTop: 20,
  },
  discoverCategoryText: {
    marginRight: 30,
    fontFamily: 'Lato-Regular',
    fontSize: 16,
    color: colors.gray,
  },
  discoverItemsWrapper: {
    paddingVertical: 20,
  },
  discoverItem: {
    width: 170,
    height: 250,
    justifyContent: 'flex-end',
    paddingHorizontal: 10,
    paddingVertical: 15,
    marginRight: 20,
  },
  discoverItemImage: {
    borderRadius: 20,
  },
  discoverItemTitle: {
    fontFamily: 'Lato-Bold',
    fontSize: 18,
    color: colors.white,
  },
  discoverItemLocationWrapper: {
    flexDirection: 'row',
    alignItems: 'center',
    marginTop: 5,
  },
  discoverItemLocationText: {
    marginLeft: 5,
    fontFamily: 'Lato-Bold',
    fontSize: 14,
    color: colors.white,
  },
  activitiesWrapper: {
    marginTop: 10,
  },
  activitiesTitle: {
    marginHorizontal: 20,
    fontFamily: 'Lato-Bold',
    fontSize: 24,
    color: colors.black,
  },
  activitiesItemsWrapper: {
    paddingVertical: 20,
  },
  activityItemWrapper: {
    justifyContent: 'flex-end',
    alignItems: 'center',
    marginRight: 20,
  },
  activityItemImage: {
    width: 36,
  },
  activityItemText: {
    marginTop: 5,
    fontFamily: 'Lato-Bold',
    fontSize: 14,
    color: colors.gray,
  },
  learnMoreWrapper: {
    marginTop: 10,
  },
  learnMoreTitle: {
    marginHorizontal: 20,
    fontFamily: 'Lato-Bold',
    fontSize: 24,
    color: colors.black,
  },
  learnMoreItemsWrapper: {
    paddingVertical: 20,
  },
  learnMoreItem: {
    width: 170,
    height: 180,
    justifyContent: 'flex-end',
    marginRight: 20,
  },
  learnMoreItemImage: {
    borderRadius: 20,
  },
  learnMoreItemText: {
    fontFamily: 'Lato-Bold',
    fontSize: 18,
    color: colors.white,
    marginHorizontal: 10,
    marginVertical: 20,
  },
});

export default Home;

完整的作業代碼可以在這里找到

轉載請註明出處，本文鏈接：https://www.uj5u.com/ruanti/397929.html

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