我是 ionic 2 的新手。我遇到了一个问题。一旦我使用 map 定义 var map; 它就在 loadMap() 功能良好。但是，如果我像 map:any; 这样定义 map ，它就不起作用。抛出这样的错误。
Error: Uncaught (in promise): TypeError: undefined is not an object (evaluating 'this.map')
import { Component } from '@angular/core';
import { NavController,Platform } from 'ionic-angular';
import { Geolocation } from 'ionic-native';
import {DataService} from '../../providers/data-service';
declare var L:any;
@Component({
selector: 'page-my-map',
templateUrl: 'my-map.html',
providers:[DataService]
})
export class MyMap {
public data: any;
map:any=null;
markersLayer;
myPositionLayer;
myCircleLayer;
showingon;
LeafIconMe;
LeafIcon;
constructor(platform: Platform, public dataService: DataService) {
platform.ready().then(() => {
Geolocation.getCurrentPosition().then((resp) => {
});
this.loadMap();
this.loadData();
});
}
loadMap(){
this.map = L.map('map', {}).setView([40.980963, 29.0966243], 10);
L.tileLayer(tileURL, {
maxZoom: 18,
attribution: ''
}).addTo(this.map);
this.map.locate({ setView: true, maxZoom: 16 });
this.dataService.getData()
.then(data => {
this.data = data;
this.data.forEach(function(veri){
console.log(veri.lat);
L.marker([veri.lat, veri.lon]).addTo(this.map);
})
});
console.log("map"+this.map);
}
loadData(){
console.log("data"+this.map);
}
}
我的 npm 列表如下所示。
npm list --depth=0
msson@ /Users/baris/ionic2/denden/msson
├── @angular/common@2.0.0
├── @angular/compiler@2.0.0
├── @angular/compiler-cli@0.6.2
├── @angular/core@2.0.0
├── @angular/forms@2.0.0
├── @angular/http@2.0.0
├── @angular/platform-browser@2.0.0
├── @angular/platform-browser-dynamic@2.0.0
├── @angular/platform-server@2.0.0
├── @ionic/app-scripts@0.0.36
├── @ionic/storage@1.0.3
├── ionic-angular@2.0.0-rc.1
├── ionic-native@2.2.3
├── ionicons@3.0.0
├── rxjs@5.0.0-beta.12
├── typescript@2.0.3
└── zone.js@0.6.21
你能给我任何解决这个问题的建议吗？提前致谢..
最佳答案
this.data.forEach(function(veri){
console.log(veri.lat);
L.marker([veri.lat, veri.lon]).addTo(this.map);
})
您需要使用 arrow function (而不是 function)来保留 this context
this.data.forEach((veri) => {
console.log(veri.lat);
L.marker([veri.lat, veri.lon]).addTo(this.map);
})
关于node.js - ionic 2 undefined is not an object 错误，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/40239847/