undefined 不是对象(评估 'this.onSubmitPressed.bind')

Question

我有一个listView通过JSON显示数据。我介绍了一个功能，并在单击每一行时，显示一个警报，包括{shop_name}。但是在第一步，它没有识别该功能。功能在同一类当我将警报放在OnPress中时，它起作用

 class SearchPage extends Component {
        constructor(props) {
          super(props);
          var dataSource = new ListView.DataSource({rowHasChanged:(r1,r2) => r1.ruid != r2.guid});
          this.state = {
            id: 'SearchPage',
            shopid: this.props.shopid,
            homesearchinpt: this.props.homesearchinpt,
            dataSource: dataSource.cloneWithRows(shopsArray),
            isLoading: true
          };
        }
        componentDidMount(){
          this.fetchData();
        }
        onSubmitPressed(){
          Alert.alert(
            'Alert Title',
            'alertMessage',
          )
        }
        fetchData() {
            fetch(REQUEST_URL)
                .then((response) => response.json())
                .then((responseData) => {
                    this.setState({
                    dataSource: this.state.dataSource.cloneWithRows(responseData),
                    loaded: true,
                });
            })
            .done();
        }
        render() {
            if (!this.state.loaded) {
                return this.renderLoadingView();
            }
            return (
                <ListView
                    dataSource={this.state.dataSource}
                    renderRow={this.renderShops}
                    style={styles.listView}
                />
            );
        }
        renderLoadingView() {
            return (
                <View style={styles.container}>
                    <Text>Loading</Text>
                </View>
            );
        }
        renderShops(shop) {
            return (

                <View style={styles.container} >
             <TouchableOpacity onPress={this.onSubmitPressed.bind(this)}>
                    <Image
              source={{uri: shop.shop_logo}}
              style={{width: 50, height: 50}}>
            </Image>
              <View>
                <Text style={styles.shop_name}>{shop.shop_name}</Text>
                <Text style={styles.shop_description}>{shop.shop_description}</Text>
              </View>
            </TouchableOpacity>
          </View>
            );
        }
};

错误：

未定义不是一个对象（评估'this.onsubmitpressed.bind'）

Answer 1

onSubmitPressed(shopName) {
  Alert.alert(
    'Alert Title',
    shopName,
  )
}

---

<TouchableOpacity onPress={() => this.onSubmitPressed(shop.shop_name)}>

Answer 2

我重写了代码，解决了问题。谢谢