foreach数组json如何反应原生?当显示元素不相同时

时间:2018-01-15 09:32:37

标签: json loops react-native display

我有一个包含5个元素的数组:

[
  {
    "id": 1,
    "title": "Title 1",
    "description": "descriptions"
  },
  {
    "id": 2,
    "title": "Title 1",
    "description": "descriptions"
  },
  {
    "id": 3,
    "title": "Title 1",
    "description": "descriptions"
  },
  {
    "id": 4,
    "title": "Title 1",
    "description": "descriptions"
  },
  {
    "id": 5,
    "title": "Title 1",
    "description": "descriptions"
  }
]

我希望它们显示如下:

<Item>
  <Text style={styles.cardText}>Title 1</Text>
  <Text style={styles.cardText} numberOfLines={2}>Description 1</Text>
</Item>
<Grid>
  <Col>
    <Item>
      <Text style={styles.cardText}>Title 2</Text>
      <Text style={styles.cardText} numberOfLines={2}>Description 2</Text>
    </Item>
  </Col>
  <Col>
    <Item>
      <Text style={styles.cardText}>Title 3</Text>
      <Text style={styles.cardText} numberOfLines={2}>Description 3</Text>
    </Item>
  </Col>
</Grid>
<Grid>
  <Col>
    <Item>
      <Text style={styles.cardText}>Title 4</Text>
      <Text style={styles.cardText} numberOfLines={2}>Description 4</Text>
    </Item>
  </Col>
  <Col>
    <Item>
      <Text style={styles.cardText}>Title 5</Text>
      <Text style={styles.cardText} numberOfLines={2}>Description 5</Text>
    </Item>
  </Col>
</Grid>

如何在React Native中显示上述内容?

我尝试使用datas.map函数但不能。 我试图添加字符串,但我认为这不是解决方案。

有解决方案吗?

谢谢大家。

2 个答案:

答案 0 :(得分:1)

对于0以外的索引,您可以chunkarray分为2部分。

constructor() {
    super();
    this.state = {
        data: [
            {
                "id": 1,
                "title": "Title 1",
                "description": "descriptions"
            },
            {
                "id": 2,
                "title": "Title 1",
                "description": "descriptions"
            },
            {
                "id": 3,
                "title": "Title 1",
                "description": "descriptions"
            },
            {
                "id": 4,
                "title": "Title 1",
                "description": "descriptions"
            },
            {
                "id": 5,
                "title": "Title 1",
                "description": "descriptions"
            }
        ],
        chunk: this.chunk
    }
} 

分块方法array

chunk(array, chunkSize) {
    return [].concat.apply([],
        array.map(function (elem, i) {
            return i % chunkSize ? [] : [array.slice(i, i + chunkSize)];
        })
    );
};

渲染项目:

render() {
    let { data, chunk } = this.state;
    let dataForChunk = [...data];
    dataForChunk.splice(0, 1); //removes 1st index of array
    let chunkedArr = chunk(dataForChunk, 2);

    return (<View style={{flex: 1}}>
        <Item>
            <Text style={styles.cardText}> {data[0].title} </Text>
            <Text style={styles.cardText} numberOfLines={2} > {data[0].description} </Text>
        </Item>
        {chunkedArr.map((arr, index) => {
            return(
                <Grid>
                    {arr.map(item => {
                        return(
                            <Col>
                                <Item>
                                    <Text style={styles.cardText} >{item.id}</Text>
                                    <Text style={styles.cardText} numberOfLines={2}>{item.description}</Text>
                                </Item>
                            </Col>
                        );
                    })}
                </Grid>
            )
        })}
    </View>)
}

答案 1 :(得分:0)

您可以使用FlatList。

考虑示例

request.args.getlist(<paramname>)

FlatList用法:

const row = [{key: 'a'}, {key: 'b'}]

在函数内部渲染视图:

<FlatList
        data={row}
        renderItem={(item) => this._renderItem(item)}
        keyExtractor={extractKey}
        extraData={row}
        />