如何在数组中的 Object 项目上设置状态

Question

我想更新数组对象中关键心脏的 state 当心脏图标被按下时它变为红色所以为此我使用反应本机图标并且我使用 heart 和 hearto 在单击它时进行切换

这是代码：

state = {      
          localAdversiment: [
            {
              title: "Ecloninear 871",
              image: require("../../assets/images/truck_image.png"),
              year: "2015",
              type: "Truck",
              status: "new",
              price: "$ 2000",
              heart: "hearto"
            }

这里是 function 按下心脏图标时调用

 handleFavourite = index => {
    const { heart } = this.state.localAdversiment[index];
    this.setState(
      {
        heart: "heart"
      }
    );
  };

这是心脏图标代码

<TouchableOpacity onPress={() => this.handleFavourite(index)}>
                <Icon
                  name={item.heart}
                  type={"AntDesign"}
                  style={{ fontSize: 18 }}
                />
              </TouchableOpacity>

请帮助我如何在单击时将心脏更新为心脏而不是心脏

Answer 1

您可以通过以下方法轻松完成

state = {      
          localAdversiment: [
            {
              id: 0,
              title: "Ecloninear 871",
              image: require("../../assets/images/truck_image.png"),
              year: "2015",
              type: "Truck",
              status: "new",
              price: "$ 2000",
              heart: "hearto",
              selected: false
            }
}

现在在 onPress 做这个

handleFavourite = (item) => {
   const { id } = item;
   this.setState({
       localAdvertisement: this.state.localAdvertisement.map((item) => {
         if(item.id === id){
           return {
              ...item,
              selected: !item.selected  
           }
         }

         return item

    })
  })
};

现在像这样渲染

             <TouchableOpacity onPress={() => this.handleFavourite(item)}>
                <Icon
                  name={item.selected ? "heart" : 'hearto'}
                  type={"AntDesign"}
                  style={{ fontSize: 18 }}
                />
              </TouchableOpacity>

希望对你有帮助

Answer 2

编辑这个 function 如下：

handleFavourite = index => {
    let updatedlocalAdversimentStates = this.state.localAdversiment;
    updatedlocalAdversimentStates[index].heart = "heart";
    this.setState(
      {
        localAdversiment: updatedlocalAdversimentStates
      }
    );
  };