Javascript 警告：Can'；t在未安装的组件上执行React状态更新。如何使用它 如何使用它？
我的代码在登录时出现问题，当我更改屏幕并完成身份验证时。我不知道解决方案是什么，但我认为错误的是，我不知道如何使用did挂载：D我寻找did挂载，但我不知道如何使用它，更重要的是，我必须找出它是如何工作的 问题 APP.jsJavascript 警告：Can'；t在未安装的组件上执行React状态更新。如何使用它 如何使用它？,javascript,react-native,react-router,Javascript,React Native,React Router,我的代码在登录时出现问题，当我更改屏幕并完成身份验证时。我不知道解决方案是什么，但我认为错误的是，我不知道如何使用did挂载：D我寻找did挂载，但我不知道如何使用它，更重要的是，我必须找出它是如何工作的 问题 APP.js import React，{useState，useffect}来自“React”； 从“@react-navigation/native”导入{NavigationContainer}”； 从“/Routes/MainStack.Routes”导入MainStack； 从
import React，{useState，useffect}来自“React”；
从“@react-navigation/native”导入{NavigationContainer}”；
从“/Routes/MainStack.Routes”导入MainStack；
从“/Routes/HomeStack.Routes”导入HomeStack；
从“@react native firebase/auth”导入身份验证；
从“/Components/Load”导入负载；
从“@react native async storage/async storage”导入异步存储；
导出默认函数App（）{
const[initializing，setInitializing]=useState（true）；
const[user，setUser]=useState（）；
异步函数onAuthStateChanged（userLoged）{
setUser（userLoged）；
如果（用户登录）{
等待AsyncStorage.setItem（“lolguide@user，JSON.stringify（userLoged））；
}
if（初始化）setInitializing（false）；
}
useffect（（）=>{
返回auth（）.onAuthStateChanged（onAuthStateChanged）；
}, []);
如果（初始化）{
返回；
}
如果（！用户）{
返回(
);
}否则{
返回(
);
}
}
从“React”导入React；
从“@react navigation/stack”导入{createStackNavigator}；
从“./组件/负载”导入负载；
从“./Routes/MainStack.Routes”导入MainStack屏幕；
从“./Pages/Home/index”导入主页；
从“./页面/配置文件”导入配置文件；
从“./Pages/Champ/index”导入Champ；
const-MainStack=createStackNavigator（）；
const HomeStackScreens=（）=>(
);
导出默认屏幕；
从“React”导入React；
从“@react navigation/stack”导入{createStackNavigator}；
从“./Pages/Login/index”导入登录名；
从“./页面/注册/索引”导入注册；
从“./组件/负载”导入负载；
从“./Routes/HomeStack.Routes”导入主页；
const-MainStack=createStackNavigator（）；
const HomeStack=（）=>(
);
出口违约本币；
import React，{useState，useffect}来自“React”；
从“/styles”导入{Container}；
从“../../Components/Header”导入标题；
从“../../Components/Load”导入负载；
从“../../Components/ChampCard”导入ChampCard；
从“react native”导入{FlatList、StatusBar、TouchableOpacity}；
从'@react-navigation/native'导入{useNavigation}；
常量Home=（）=>{
const[loading，setLoading]=useState（true）；
const[champs，setChamps]=useState（[]）；
const navigation=useNavigation（）；
功能导航器（电视台、道具）{
navigation.navigate（tela，{item:JSON.stringify（props）}）；
}
异步函数getData（）{
待命(
"https://ddragon.leagueoflegends.com/cdn/11.10.1/data/pt_BR/champion.json"
)
.然后（（res）=>res.json（））
.then（（json）=>setChamps（Object.values（json.data））；
设置加载（假）；
}
useffect（（）=>{
getData（）；
}, []);
如果（装载）{
返回；
}
返回(
{champs.length>0(
item.key}
renderItem={（项目）=>(
纳维加（“冠军”，项目）}>
)}
contentContainerStyle={{paddingBottom:65}
showsVerticalScrollIndicator={false}
/>
) : (
)}
);
};
导出默认主页；
import React，{useState}来自“React”；
从“react native”导入{Image，Dimensions，PixelRatio，StyleSheet}；
从“世博会状态栏”导入{StatusBar}；
从“expo linear gradient”导入{LinearGradient}；
从“@react-navigation/native”导入{useNavigation}”；
从“@react native async storage/async storage”导入异步存储；
进口{
集装箱，
标志
文本输入，
文本，
按钮
纽特纳里亚，
图像盒，
绝对视野，
}来自“/样式”；
从“../../Components/Load”导入负载；
从“@react native firebase/auth”导入身份验证；
常量宽度百分比TODP=（宽度百分比）=>{
const screenWidth=维度.get（“窗口”）.width；
返回PixelRatio.roundToNearestPixel(
（屏幕宽度*parseFloat（宽度百分比））/100
);
};
常量高度百分比TODP=（高度百分比）=>{
const screenHeight=尺寸。获取（“窗口”）。高度；
返回PixelRatio.roundToNearestPixel(
（屏幕高度*parseFloat（高度百分比））/100
);
};
const styles=StyleSheet.create({
线性梯度：{
高度：高度百分比TODP（“120%”），
弹性：1，
},
});
常量登录=（）=>{
const[email，setEmail]=useState（“”）；
const[password，setPassword]=useState（“”）；
const[isLoading，setIsLoading]=useState（false）；
const navigation=useNavigation（）；
常量handleSend=（）=>{
如果（电子邮件和密码）{
设置加载（真）；
auth（）
.使用电子邮件和密码登录（电子邮件、密码）
.然后（（）=>{
导航。导航（“主屏幕”）；
设置加载（假）；
})
.catch（（错误）=>{
if（错误代码）{
控制台错误（error）；
}
});
设置加载（假）；
}否则{
警报（“预检系统！”）；
}
};
const handleRegisterNavigate=（）=>{
导航。导航（“注册”）；
};
如果（孤岛加载）{
返回；
}
返回(
最佳课程安排
setEmail（t）}
/>
设置密码（t）}
/>
诱捕者
登记员
);
};
出口d
ERROR Warning: Can't perform a React state update on an unmounted component. This is a no-op, but it indicates a memory leak in your application. To fix, cancel all subscriptions and asynchronous tasks in a useEffect cleanup function.
in Home (at SceneView.tsx:122)
(...)
in StackNavigator (at MainStack.routes.js:11)
in HomeStack (at App.js:32)
import React, { useState, useEffect } from "react";
import { Container } from "./styles";
import Header from "../../Components/Header";
import Load from "../../Components/Load";
import ChampCard from "../../Components/ChampCard";
import { FlatList, StatusBar, TouchableOpacity } from "react-native";
import { useNavigation } from '@react-navigation/native';
const Home = () => {
const [loading, setLoading] = useState(true);
const [champs, setChamps] = useState([]);
const navigation = useNavigation();
function navegar(tela, props) {
navigation.navigate(tela, {item: JSON.stringify(props)});
}
async function getData() {
await fetch(
"https://ddragon.leagueoflegends.com/cdn/11.10.1/data/pt_BR/champion.json"
)
.then((res) => res.json())
.then((json) => setChamps(Object.values(json.data)));
setLoading(false);
}
useEffect(() => {
getData();
}, []);
if (loading) {
return <Load />;
}
return (
<>
<Container>
<Header type="NormalHeader"/>
{champs.length > 0 ? (
<FlatList
data={champs}
keyExtractor={(item) => item.key}
renderItem={(item) => (
<TouchableOpacity onPress={() => navegar("Champ", item)}>
<ChampCard item={item}/>
</TouchableOpacity>
)}
contentContainerStyle={{ paddingBottom: 65 }}
showsVerticalScrollIndicator={false}
/>
) : (
<Load />
)}
</Container>
<StatusBar backgroundColor="#000"/>
</>
);
};
export default Home;
import React, { useState } from "react";
import { Image, Dimensions, PixelRatio, StyleSheet } from "react-native";
import { StatusBar } from "expo-status-bar";
import { LinearGradient } from "expo-linear-gradient";
import { useNavigation } from "@react-navigation/native";
import AsyncStorage from '@react-native-async-storage/async-storage';
import {
Container,
Logo,
TextInput,
Text,
Button,
ButtonArea,
ImageBox,
ViewAbsolute,
} from "./styles";
import Load from "../../Components/Load";
import auth from "@react-native-firebase/auth";
const widthPercentageToDP = (widthPercent) => {
const screenWidth = Dimensions.get("window").width;
return PixelRatio.roundToNearestPixel(
(screenWidth * parseFloat(widthPercent)) / 100
);
};
const heightPercentageToDP = (heightPercent) => {
const screenHeight = Dimensions.get("window").height;
return PixelRatio.roundToNearestPixel(
(screenHeight * parseFloat(heightPercent)) / 100
);
};
const styles = StyleSheet.create({
linearGradient: {
height: heightPercentageToDP("120%"),
flex: 1,
},
});
const Login = () => {
const [email, setEmail] = useState("");
const [password, setPassword] = useState("");
const [isLoading, setIsLoading] = useState(false);
const navigation = useNavigation();
const handleSend = () => {
if (email && password) {
setIsLoading(true);
auth()
.signInWithEmailAndPassword(email, password)
.then( () => {
navigation.navigate("HomeScreen");
setIsLoading(false);
})
.catch((error) => {
if (error.code) {
console.error(error);
}
});
setIsLoading(false);
} else {
alert("Preencha os campos!");
}
};
const handleRegisterNavigate = () => {
navigation.navigate("SignUp");
};
if (isLoading) {
return <Load />;
}
return (
<ViewAbsolute>
<Container>
<LinearGradient
colors={["#C28F2C", "#000", "#004840"]}
style={styles.linearGradient}
start={{ x: 0, y: -0.2 }}
end={{ x: 0, y: 1.2 }}
>
<Logo>
<Image
source={require("../../Assets/lolGuideIcon.png")}
style={{ height: 75, width: 80 }}
resizeMode="stretch"
/>
</Logo>
<Text>O primeiro passo para se tornar um campeão é a iniciativa</Text>
<TextInput
placeholder="Email"
keyboardType="email-address"
margin_top="50px"
value={email}
onChangeText={(t) => setEmail(t)}
/>
<TextInput
placeholder="Senha"
margin_top="5px"
secureTextEntry
value={password}
onChangeText={(t) => setPassword(t)}
/>
<ButtonArea>
<Button width="80px" margin_top="20px" onPress={handleSend}>
<Text>Entrar</Text>
</Button>
<Button
width="110px"
margin_top="10px"
onPress={handleRegisterNavigate}
>
<Text>Registrar</Text>
</Button>
</ButtonArea>
<ImageBox>
<Image
source={require("../../Assets/Pyke-transparente.png")}
style={{
height: 230,
width: 260,
}}
/>
</ImageBox>
<StatusBar style="auto" backgroundColor="transparent" />
</LinearGradient>
</Container>
</ViewAbsolute>
);
};
export default Login;
import React, { useState, useEffect } from "react";
import { NavigationContainer } from "@react-navigation/native";
import MainStack from "./Routes/MainStack.routes";
import HomeStack from "./Routes/HomeStack.routes";
import auth from "@react-native-firebase/auth";
import Load from "./Components/Load";
import AsyncStorage from "@react-native-async-storage/async-storage";
export default function App() {
const [initializing, setInitializing] = useState(true);
const [user, setUser] = useState();
useEffect(() => {
auth().onAuthStateChanged((userLogged) => {
setUser(userLogged);
if (userLogged) {
AsyncStorage.setItem("lolguide@user", JSON.stringify(userLogged));
}
if (initializing) setInitializing(false);
});
}, [initializing]);
if (initializing) {
return <Load />;
}
if (!user) {
return (
<NavigationContainer>
<MainStack />
</NavigationContainer>
);
} else {
return (
<NavigationContainer>
<HomeStack />
</NavigationContainer>
);
}
}
import React, { useState } from "react";
import { Image, Dimensions, PixelRatio, StyleSheet } from "react-native";
import { StatusBar } from "expo-status-bar";
import { LinearGradient } from "expo-linear-gradient";
import { useNavigation } from "@react-navigation/native";
import AsyncStorage from '@react-native-async-storage/async-storage';
import {
Container,
Logo,
TextInput,
Text,
Button,
ButtonArea,
ImageBox,
ViewAbsolute,
} from "./styles";
import Load from "../../Components/Load";
import auth from "@react-native-firebase/auth";
const widthPercentageToDP = (widthPercent) => {
const screenWidth = Dimensions.get("window").width;
return PixelRatio.roundToNearestPixel(
(screenWidth * parseFloat(widthPercent)) / 100
);
};
const heightPercentageToDP = (heightPercent) => {
const screenHeight = Dimensions.get("window").height;
return PixelRatio.roundToNearestPixel(
(screenHeight * parseFloat(heightPercent)) / 100
);
};
const styles = StyleSheet.create({
linearGradient: {
height: heightPercentageToDP("120%"),
flex: 1,
},
});
const Login = () => {
const [email, setEmail] = useState("");
const [password, setPassword] = useState("");
const [isLoading, setIsLoading] = useState(false);
const navigation = useNavigation();
const handleSend = () => {
if (email && password) {
setIsLoading(true);
auth()
.signInWithEmailAndPassword(email, password)
//.then( () => {
// navigation.navigate("HomeScreen"); REMOVE THIS BLOCK
// setIsLoading(false);
//})
.catch((error) => {
if (error.code) {
console.error(error);
}
});
setIsLoading(false);
} else {
alert("Preencha os campos!");
}
};
const handleRegisterNavigate = () => {
navigation.navigate("SignUp");
};
if (isLoading) {
return <Load />;
}
return (
<ViewAbsolute>
<Container>
<LinearGradient
colors={["#C28F2C", "#000", "#004840"]}
style={styles.linearGradient}
start={{ x: 0, y: -0.2 }}
end={{ x: 0, y: 1.2 }}
>
<Logo>
<Image
source={require("../../Assets/lolGuideIcon.png")}
style={{ height: 75, width: 80 }}
resizeMode="stretch"
/>
</Logo>
<Text>O primeiro passo para se tornar um campeão é a iniciativa</Text>
<TextInput
placeholder="Email"
keyboardType="email-address"
margin_top="50px"
value={email}
onChangeText={(t) => setEmail(t)}
/>
<TextInput
placeholder="Senha"
margin_top="5px"
secureTextEntry
value={password}
onChangeText={(t) => setPassword(t)}
/>
<ButtonArea>
<Button width="80px" margin_top="20px" onPress={handleSend}>
<Text>Entrar</Text>
</Button>
<Button
width="110px"
margin_top="10px"
onPress={handleRegisterNavigate}
>
<Text>Registrar</Text>
</Button>
</ButtonArea>
<ImageBox>
<Image
source={require("../../Assets/Pyke-transparente.png")}
style={{
height: 230,
width: 260,
}}
/>
</ImageBox>
<StatusBar style="auto" backgroundColor="transparent" />
</LinearGradient>
</Container>
</ViewAbsolute>
);
};
export default Login;