Fetch -React Native.Error:on 函数

Question

undefined 不是函数（正在评估 'this_submitForm()'）。...*我在调用函数时遇到此错误。我是新来的原生反应，我已经搜索了每个地方但我没有得到任何解决方案。如果有解决方案，请添加示例代码以便更好地理解。

• 我在这里发布我的代码：*

  var React = require('react-native');
  
  var {
    AppRegistry,
    StyleSheet,
    Text,
    View,
    Navigator,
    TouchableOpacity,
  } = React;
  
   var SCREEN_WIDTH = require('Dimensions').get('window').width;
   var PageOne = React.createClass({
   onEmailChange(email) {
      let s = this.state;
      s.email = email;
      this.setState(s);
  },
  
    render() {
      return (
        <View style={[styles.container, {backgroundColor: 'green'}]}>
          <Text style={styles.welcome}>Greetings!</Text>
          <TouchableOpacity onPress={this._handlePress}>
            <View style={{paddingVertical: 10, paddingHorizontal: 20, backgroundColor: 'black'}}>
             <TextInput
                   onChangeText={this.onEmailChange}
                   placeholderTextColor="#a0a0a0"
                   placeholder="email"
                   underlineColorAndroid='transparent'/>
            </View>
          </TouchableOpacity  onPress={this._submitForm()}>
         </View>
      )
    },
  });
  
   var PageTwo = React.createClass({
  
    render() {
      return (
        <View style={[styles.container, {backgroundColor: 'green'}]}>
          <Text style={styles.welcome}>Greetings!</Text>
          <TouchableOpacity onPress={this._handlePress}>
            <View style={{paddingVertical: 10, paddingHorizontal: 20, backgroundColor: 'black'}}>
              <Text style={styles.welcome}>Go to page two</Text>
            </View>
          </TouchableOpacity>
         </View>
      )
    },
  });
  
  class VerifyMe extends Component {
  
  constructor(props) {
      super(props);
  
      this.state = {
          email: '',
          password: '',
      }
  }
  
  _renderScene(route, navigator) {
      if (route.id === 1) {
          return <PageOne navigator={navigator}/>
      } else if (route.id === 2) {
          return <PageTwo navigator={navigator}/>
      } 
  }
  

  _submitForm() { fetch(baseURL+'users/loginUser', { 方法：'发布'， 正文： JSON.stringify({ config_name: '默认', 电子邮件：this.state.email，

      })
          .then((response) => response.json())
          .then((responseJson) => {
              if (response.data.responsecode === 1) {
                  this.props.navigator.push({id: 2,});
              }
          })
          .catch((error) => {
              console.error(error);
          })
  });
  

  } 使成为（） { 返回 （ ); } }

Answer 1

您尝试在 PageOne 中使用 this._submitFrom 但您在 PageTwo 中定义了它，请尝试使用以下代码

var React = require('react-native');

var {
  AppRegistry,
  StyleSheet,
  Text,
  View,
  Navigator,
  TouchableOpacity,
} = React;

 var SCREEN_WIDTH = require('Dimensions').get('window').width;
 var PageOne = React.createClass({
 getInitialState () {
    return {
       email:'', //add your initial state for this class here
  };
},
 onEmailChange(email) {
    //let s = this.state;
    //s.email = email;          // no need of these lines
    this.setState({
      email:email
    });
},
_submitForm() { 
fetch(baseURL+'users/loginUser', { 
method: 'post', body: JSON.stringify({ config_name: 'default', email: this.state.email
})
        .then((response) => response.json())
        .then((responseJson) => {
            if (response.data.responsecode === 1) {
                this.props.navigator.push({id: 2,});
            }
        })
        .catch((error) => {
            console.error(error);
        })
});
}

  render() {
    return (
      <View style={[styles.container, {backgroundColor: 'green'}]}>
        <Text style={styles.welcome}>Greetings!</Text>
        <TouchableOpacity onPress={this._handlePress}>
          <View style={{paddingVertical: 10, paddingHorizontal: 20, backgroundColor: 'black'}}>
           <TextInput
                 onChangeText={this.onEmailChange}
                 placeholderTextColor="#a0a0a0"
                 placeholder="email"
                 underlineColorAndroid='transparent'/>
          </View>
        </TouchableOpacity  onPress={this._submitForm.bind(this)}> //need to use bind
       </View>
    )
  },
});

 var PageTwo = React.createClass({

  render() {
    return (
      <View style={[styles.container, {backgroundColor: 'green'}]}>
        <Text style={styles.welcome}>Greetings!</Text>
        <TouchableOpacity onPress={this._handlePress}>
          <View style={{paddingVertical: 10, paddingHorizontal: 20, backgroundColor: 'black'}}>
            <Text style={styles.welcome}>Go to page two</Text>
          </View>
        </TouchableOpacity>
       </View>
    )
  },
});

class VerifyMe extends Component {

constructor(props) {
    super(props);

    this.state = {
        email: '',
        password: '',
    }
}

_renderScene(route, navigator) {
    if (route.id === 1) {
        return <PageOne navigator={navigator}/>
    } else if (route.id === 2) {
        return <PageTwo navigator={navigator}/>
    } 
}

} render() { return ( ); } }