在 React Native 中获取后的条件渲染

Question

react native fetch后怎么条件渲染？不想渲染组件 1.Successful 使用 responseData 获取 2.Network请求失败 3.If 从服务器

返回了空的 responseData

目前我只显示成功的result.I想显示失败的情况also.How我在不成功后渲染Text组件fetch.Following是我的代码

  onPressSubmit() {

    fetch("xxxx", {
      method: "POST",
      headers: {
        Accept: "application/json",
        "Content-Type": "application/json"
      },
      body: JSON.stringify({
        url: this.state.url
      })
    })
     .then((response) => response.json())
    .then((responseData) =>
    {
            this.setState({
            res:responseData.message,
            showLoading: false
                    }, () => console.log(this.state.res));
        }).catch((error) => {
      console.error(error);
    });
  }
  renderArticle(){
      const {title} = this.state.res;
      const {image} = this.state.res;
      const {text} = this.state.res;
      const {id} = this.state.res;
      const {author} =this.state.res;
      const {html} = this.state.res;


              return (
           <TouchableOpacity 
            onPress={() => Actions.addNewarticle({heading:title, authorname:author, description:text, htmlcon:html})}
          >
            <CardSection>
              <View style={{ flexDirection: "row" }}>
                <Image
                  source={{ uri:image }}
                  style={styles.thumbnail_style}
                />
                <Text style={styles.textStyle}>{title}</Text>
              </View>
            </CardSection>
          </TouchableOpacity>
          ); 
  }
render(){
return(
 <View>
{this.renderArticle()}
 </View>
);
}

Answer 1

创建 renderNetworkFailure 方法，您可以在其中显示任何您想要的内容。进入render方法。检查您的响应数据是否可用？我检查了空白字符串。

render(){
const isResponseData = (this.state.res == '') ? this.renderNetworkFailure() : this.renderArticle()
return(
 <View>
{isResponseData}
 </View>
);

Answer 2

我认为更准确地说，这就是你的答案的样子，如果你也想显示网络故障，那么你也必须为它保留一个状态变量。（我也是 react-native 的初学者如有不妥请指正）

render(){
return(
<View>
{(this.state.err)?this.networkFailure():({this.state.res.length? this.renderArticle():this.renderNothing()})}
</View>
)
}

在 React Native 中获取后的条件渲染

Conditional rendering after fetch in react native

javascript

reactjs

conditional-rendering

react-native