问题描述
似乎如果我注释掉this.setState({logged_in: true});"行，第 63 行，我不会收到错误消息.我的猜测是，我试图根据用户是否登录来更改呈现函数中显示的内容的方式是导致此错误的原因.有什么想法吗?
it seems that if I comment out the line "this.setState({logged_in: true});", line 63, that I don't get the error. My guess is that something about the way I'm trying to change the content being displayed in the render function based on if the user is logged in or not is what is the cause of this error. Any ideas?
我觉得我在理解 React Native 的一些非常基础的知识方面取得了一些进展.尽管我的代码可能不漂亮，但直到最近添加了一些代码才有效.我在 IOS 模拟器中收到一条错误消息，内容为无效数据消息 - 所有长度必须为 8".不幸的是，它没有给我任何我理解的细节，例如行号.
I've been making some slight progress in understanding some very basics of React Native, I feel like. Although my code might not be pretty, up until some recent additions it worked. I'm recieving an error message in the IOS Simulator that reads "Invalid data message - all must be length: 8". It unfortunately isn't giving me any specifics that I understand, such as linenumbers.
如果这是转帖，我真诚地道歉，我一直在 google 和 stackoverflow 上疯狂寻找解决此错误的方法，但在我的搜索中没有成功.
I sincerely apologise if this is a repost, I've been looking like crazy on google and stackoverflow to find a solution to this error but have been unsuccessful in my searches.
我已经审查了我在 fetch 中使用的 url，因为它是公司内部早期测试的地址，但我 99.99% 确信这不是问题所在.
I've censored the url I've using in fetch since it is an adress for testing within the company in very early stages, but I am 99,99% sure that's not where the problem lies.
我的 index.ios.js:
My index.ios.js:
import React, { Component } from 'react';
import {
AppRegistry,
StyleSheet,
Text,
View,
Button,
Alert,
TextInput,
TouchableHighlight,
Image,
AlertIOS,
PickerIOS,
} from 'react-native';
var REASONS = {
sick: {
name: "sjuk"
},
vacation: {
name: "semester"
},
child_care: {
name: "vård av barn"
},
parenting: {
name: "föräldraledig"
},
general: {
name: "övrigt"
},
};
export default class mbab_franvaro extends Component {
constructor(props) {
super(props);
this.state = {username: '', password: '', logged_in: false, reason: 'sjuk'};
}
logout(){
this.setState({logged_in: false});
this.username = ""; this.password = "";
}
login(){
if(this.state.username == "" || this.state.password == ""){
AlertIOS.alert("Fel", "Vänligen fyll i alla fält.");
}
else{
fetch("MY_PRIVATAE_COMPANY_URL", {
method: "POST",
headers: {
'Accept': 'application/x-www-form-urlencoded',
'Content-Type': 'application/x-www-form-urlencoded',
},
body: "username=" + this.state.username + "&password=" + this.state.password,
})
.then((response) => response.json())
.then((response) => {
if(JSON.stringify(response.body).replace(new RegExp('"', 'g'), '').match("Inloggad")){
this.username = this.state.username; this.password = this.state.password;
this.setState({logged_in: true});
//AlertIOS.alert("Hej!", "Välkommen " + this.username + "!");
}
else{
AlertIOS.alert(
"Fel",
JSON.stringify(response.body).replace(new RegExp('"', 'g'), '')
);
}
})
.catch((error) => {
AlertIOS.alert("error", error);
})
.done();
}
}
render(){
if(this.state.logged_in){
//sidan för frånvarorapportering
return (
<View style={styles.container}>
/*<TouchableHighlight style={styles.logout_button} onPress={() => this.logout()}>
<Text style={styles.login_button_text}>Logga ut</Text>
</TouchableHighlight>*/
<View style={styles.report_wrapper}>
<Text style={styles.header}>Frånvarorapportering</Text>
<Text>Ange anledning och hur stor del av dagen du blir frånvarande.</Text>
<PickerIOS
selectedValue={this.state.reason}
onValueChange={(reason) => this.setState({reason})}>
{Object.keys(REASONS).map((reason) => (
<PickerItemIOS
key={reason}
value={reason}
label={REASONS[reason].name}
/>
))}
</PickerIOS>
</View>
</View>
);
}
else{
//inloggningssidan
return (
<View style={styles.container}>
<Image resizeMode="center" style={styles.logo} source={require('./app/res/logo_cmyk.png')} />
<TextInput
placeholder="Namn"
autocorrect={false}
style={styles.text_box}
onChangeText={(username) => this.setState({username})}
/>
<TextInput
placeholder="Lösenord"
autocorrect={false}
secureTextEntry={true}
style={styles.text_box}
onChangeText={(password) => {this.setState({password})}}
/>
<TouchableHighlight style={styles.login_button} onPress={() => this.login()}>
<Text style={styles.login_button_text}>Logga in</Text>
</TouchableHighlight>
</View>
);
}
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
justifyContent: 'center',
alignItems: 'center',
backgroundColor: '#F4F4F4',
},
report_wrapper: {
flex: 1,
},
logout_button: {
flex: 0,
flexDirection: "row",
justifyContent: "center",
alignItems: "center",
marginLeft: 10,
marginRight: 10,
marginTop: 30,
marginBottom: 2,
padding: 10,
backgroundColor: "#003878"
},
login_button: {
flex: 0,
flexDirection: "row",
justifyContent: "center",
alignItems: "center",
marginLeft: 10,
marginRight: 10,
marginTop: 2,
marginBottom: 2,
padding: 10,
backgroundColor: "#003878"
},
login_button_text: {
color: "white",
fontSize: 20,
flex: 1,
textAlign: "center",
},
logo: {
//flex: 1,
},
text_box: {
height: 40,
flex: 0,
backgroundColor: "white",
marginLeft: 10,
marginRight: 10,
marginTop: 2,
marginBottom: 2,
padding: 10
},
header: {
color: "#84754E",
fontSize: 25,
marginTop: 30,
},
});
AppRegistry.registerComponent('mbab_franvaro', () => mbab_franvaro);
推荐答案
我在使用 ScrollView 时也遇到了同样的错误.
我花了 2 天时间才找到解决方案.
我没有从 react-native 导入 ScrollView.
检查您是否已导入 Picker.:)
I was also getting the same error while using ScrollView.
Took me 2 days to figure out the solution.
I wasn't importing ScrollView from react-native.
Check if you've imported the Picker or not. :)
这篇关于错误:“无效的数据消息 - 所有长度必须为:8"- PickerIOS的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！