使用 Expo 不在 MapView 上呈现的标记

Question

我正在使用 Expo 和 React Native 渲染 MapView 并尝试显示一些基本的 Markers，但是我什至无法显示默认的。

下面是传递给 sites 的全局状态的数据：

const sampleSiteMarkers = [
    {
        id: 1,
        title: 'Twin Lakes Hidden Spot',
        description: 'Beautiful view of Twin Lakes off this hidden forest road.',
        coordinate: {
            latitude: -106.391015,
            longitude: 39.085855
        }
    },
    {
        id: 2,
        title: 'Lily Lake',
        description: 'Nice view of the lilypads in this secluded spot, but a pretty tough road to reach it.',
        coordinate: {
            latitude: -106.368051,
            longitude: 39.351661
        }
    },
    {
        id: 3,
        title: 'Slide Lake',
        description: 'Pretty riverside camping, but a REALLY nasty road to get there.',
        coordinate: {
            latitude: -106.389204,
            longitude: 39.372171
        }
    }
];

下面是我渲染实际 MapView 的代码。请注意 MapView 渲染良好，但 Markers 本身不会出现。

// 3rd party libraries - core
import React from 'react';
import {View, Text, StyleSheet} from 'react-native';
import {MapView} from 'expo';

const {Marker} = MapView;
// 3rd party libraries - additional
import _ from 'lodash';


const SearchMap = ({mapLoaded, lastKnownRegion, updateRegion, sites}) => {
    const {fillScreen} = styles;

    const renderSites = () => {
      // sites I showed at the top of this issue come in fine from  props
        const renderedSites = _.map(sites, site => {
            const {title, description, coordinate, id} = site;

            return (
                <Marker
                    key={id}
                    title={title}
                    description={description}
                    coordinate={coordinate}
                />
            );
        });

        // if I inspect renderedSites, I see the Marker element, but it doesn't render
        return renderedSites;
    };

    const renderMap = () => {
        return (
            <MapView
                style={fillScreen}
                initialRegion={lastKnownRegion}
                onRegionChangeComplete={updateRegion}
                rotateEnabled={false}
            >

                {renderSites()}

            </MapView>
        )
    };

    return (
        <View style={fillScreen}>
            {renderMap()}
        </View>
    );

};

const styles = StyleSheet.create({
    fillScreen: {
        flex: 1
    }
});

我查看了文档和其他 Whosebug 帖子，但我不明白为什么它无法呈现。

我是不是遗漏了什么明显的东西？提前致谢。

Answer 1

拜托。这很尴尬。

原来我确实错过了一些明显的东西。

我翻转了经度和纬度值。哇。

它应该是这样的，现在渲染得很好。

const sampleSiteMarkers = [
    {
        id: 1,
        title: 'Twin Lakes Hidden Spot',
        description: 'Beautiful view of Twin Lakes off this hidden forest road.',
        coordinate: {
            longitude: -106.391015,
            latitude: 39.085855
        }
    },
    {
        id: 2,
        title: 'Lily Lake',
        description: 'Nice view of the lilypads in this secluded spot, but a pretty tough road to reach it.',
        coordinate: {
            longitude: -106.368051,
            latitude: 39.351661
        }
    },
    {
        id: 3,
        title: 'Slide Lake',
        description: 'Pretty riverside camping, but a REALLY nasty road to get there.',
        coordinate: {
            longitude: -106.389204,
            latitude: 39.372171
        }
    }
];

浪费 5 个多小时真是令人沮丧，我确定我已经检查过了。但是，嘿，如果还有其他人遇到这个问题……双重、三次检查您是否插入了正确的 lat/lng。

使用 Expo 不在 MapView 上呈现的标记

Markers not rendering on MapView with Expo

react-native

expo

react-native-maps