this.dataList.forEach((s) => { const point = s.latest_position.split(',').map(Number); const marker = new BMapGL.Marker(new BMapGL.Point(...point)); // 在地图上添加点标记 this.map.addOverlay(marker); const opts = { width: 220, height: 150, title: "集装箱信息", offset: new BMapGL.Size(0, -10) }解释这段代码

这段代码使用 forEach() 方法遍历 this.dataList 数组中的每个元素，并对其中的每个元素进行标记操作。具体来说，对于每个元素，我们首先将其 latest_position 属性解析为经纬度坐标，并创建一个 BMapGL.Point 对象表示该坐标点。然后，我们使用该坐标点创建一个 BMapGL.Marker 对象，并将其添加到 this.map 对象表示的地图上。接下来，我们创建一个 opts 对象，用于设置标记的信息窗口的参数，包括宽度、高度、标题和偏移量。最后，我们可以在标记上添加事件监听器，以便在用户点击标记时显示信息窗口等操作。

相关问题

import React, { useState, useCallback } from "react"; import { View } from "@tarojs/components"; import { LgSelepicker } from "lancoo-ui-mobile"; import "../index.scss"; export const Jsx = () => { const dataList = ["全部", "小学", "初中", "高中"]; const [choIndex, setChoIndex] = useState(0); const handleSelect = useCallback((value) => { const _choIndex = dataList.findIndex((item) => item === value); setChoIndex(_choIndex); }, []); return ( <View className="iframe__viewport"> <View className="viewport__title">B款下拉框</View> <View className="viewport__main"> <LgSelepicker type="B" dataList={dataList} choIndex={choIndex} changeSele={handleSelect} /> </View> </View> ); }; 改成类组件写法

import React, { Component } from "react";
import { View } from "@tarojs/components";
import { LgSelepicker } from "lancoo-ui-mobile";
import "../index.scss";

class Jsx extends Component {
constructor(props) {
super(props);
this.state = {
dataList: ["全部", "小学", "初中", "高中"],
choIndex: 0
};
}

handleSelect = (value) => {
const { dataList } = this.state;
const choIndex = dataList.findIndex((item) => item === value);
this.setState({ choIndex });
};

render() {
const { dataList, choIndex } = this.state;

return (
<View className="iframe__viewport">
<View className="viewport__title">B款下拉框</View>
<View className="viewport__main">
<LgSelepicker
type="B"
dataList={dataList}
choIndex={choIndex}
changeSele={this.handleSelect}
/>
</View>
</View>
);
}
}

export default Jsx;