我想创建一个像这样工作的谷歌地图组件:https://jsfiddle.net/gvvy5vxz/2/
它是基于这个:https://developers.google.com/maps/documentation/javascript/examples/overlay-simple
我是typescript的新手，我被原型实现困住了，特别是这个JS片段:
USGSOverlay.prototype = new google.maps.OverlayView();
USGSOverlay(bounds, image, map) {
// Initialize all properties.
this.bounds_ = bounds;
this.image_ = image;
this.map_ = map;
// Define a property to hold the image's div. We'll
// actually create this div upon receipt of the onAdd()
// method so we'll leave it null for now.
this.div_ = null;
// Explicitly call setMap on this overlay.
this.setMap(map);
}
我不知道如何以typescript的方式翻译，以及如何正确声明事物。
我想我应该创建一个类usgoverlay扩展google.maps.OverlayView，但它不工作。
class USGSOverlay extends google.maps.OverlayView{
bounds_;
image_;
map_;
div_;
constructor(bounds, image, map){
// Initialize all properties.
this.bounds_ = bounds;
this.image_ = image;
this.map_ = map;
// Define a property to hold the image's div. We'll
// actually create this div upon receipt of the onAdd()
// method so we'll leave it null for now.
this.div_ = null;
// Explicitly call setMap on this overlay.
this.setMap(map);
}
}
这是我的工作基组件。它在#map:
内部创建了一个简单的映射import { Component } from '@angular/core';
declare const google: any;
/*
/* Component Map
*/
@Component({
selector: 'map',
template: `
<div id="map"></div>
`,
styles: [
`#map{ width:100%; height:100%; position: absolute; width:100%; height:100%; top:0; left:0;}`
],
})
export class MapComponent {
ngOnInit(){
google.maps.event.addDomListener(window, 'load', this.initMap);
}
initMap() {
const map = new google.maps.Map(document.getElementById('map'), {
zoom: 11,
center: {lat: 62.323907, lng: -150.109291},
mapTypeId: google.maps.MapTypeId.SATELLITE
});
const bounds = new google.maps.LatLngBounds(
new google.maps.LatLng(62.281819, -150.287132),
new google.maps.LatLng(62.400471, -150.005608));
}
}
这是我的工作(使用离子2):
-
使用以下命令:
npm install typings --global typings install dt~google.maps --global --save typings install google.maps --global -
添加"输入/* .d。在你的tsconfig.json:
"include": [ "src/**/*.ts", "typings/*.d.ts" ] -
下面是TypeScript代码:
import { Component, ViewChild, ElementRef } from '@angular/core'; import { NavController } from 'ionic-angular'; // import typings import { } from '@types/googlemaps'; /* /* Component Map */ @Component({ selector: 'page-overlay', templateUrl: 'overlay.html' }) export class OverlayPage { @ViewChild('map') mapElement: ElementRef; map: any; // weird syntax, I know, but it works constructor(public navCtrl: NavController) { } USGSOverlay = class extends google.maps.OverlayView { bounds_: any; image_: any; map_: any; div_: any; constructor(bounds, image, private map) { super(); // Initialize all properties. this.bounds_ = bounds; this.image_ = image; this.map_ = map; // Define a property to hold the image's div. We'll // actually create this div upon receipt of the onAdd() // method so we'll leave it null for now. this.div_ = null; // Explicitly call setMap on this overlay. this.setMap(map); this.set } /** * onAdd is called when the map's panes are ready and the overlay has been * added to the map. */ onAdd() { const div = document.createElement('div'); div.style.borderStyle = 'none'; div.style.borderWidth = '0px'; div.style.position = 'absolute'; // Create the img element and attach it to the div. const img = document.createElement('img'); img.src = this.image_; img.style.width = '100%'; img.style.height = '100%'; img.style.position = 'absolute'; div.appendChild(img); this.div_ = div; // Add the element to the "overlayLayer" pane. const panes = this.getPanes(); panes.overlayLayer.appendChild(div); }; draw() { // We use the south-west and north-east // coordinates of the overlay to peg it to the correct position and size. // To do this, we need to retrieve the projection from the overlay. const overlayProjection = this.getProjection(); // Retrieve the south-west and north-east coordinates of this overlay // in LatLngs and convert them to pixel coordinates. // We'll use these coordinates to resize the div. const sw = overlayProjection.fromLatLngToDivPixel(this.bounds_.getSouthWest()); const ne = overlayProjection.fromLatLngToDivPixel(this.bounds_.getNorthEast()); // Resize the image's div to fit the indicated dimensions. const div = this.div_; div.style.left = sw.x + 'px'; div.style.top = ne.y + 'px'; div.style.width = (ne.x - sw.x) + 'px'; div.style.height = (sw.y - ne.y) + 'px'; }; // The onRemove() method will be called automatically from the API if // we ever set the overlay's map property to 'null'. onRemove() { this.div_.parentNode.removeChild(this.div_); this.div_ = null; }; }; ngOnInit() { this.loadMap(); var bounds = new google.maps.LatLngBounds( new google.maps.LatLng(62.281819, -150.287132), new google.maps.LatLng(62.400471, -150.005608)); // The photograph is courtesy of the U.S. Geological Survey. var srcImage = 'https://developers.google.com/maps/documentation/' + 'javascript/examples/full/images/talkeetna.png'; const overlay = new this.USGSOverlay(bounds, srcImage, this.map); //overlay.setMap(this.map); } ionViewDidLoad() { this.loadMap(); var bounds = new google.maps.LatLngBounds( new google.maps.LatLng(62.281819, -150.287132), new google.maps.LatLng(62.400471, -150.005608)); // The photograph is courtesy of the U.S. Geological Survey. var srcImage = 'https://developers.google.com/maps/documentation/' + 'javascript/examples/full/images/talkeetna.png'; const overlay = new this.USGSOverlay(bounds, srcImage, this.map); //overlay.setMap(this.map); } loadMap() { let latLng = new google.maps.LatLng(62.323907, -150.109291); var mapOptions = { zoom :15, center : latLng, enableHighAccuracy: true, timeout: 5000, maximumAge: 0 }; this.map = new google.maps.Map(this.mapElement.nativeElement, mapOptions); } }
我的工作方式很好…
import { Component } from '@angular/core';
declare const google: any;
class USGSOverlay extends google.maps.OverlayView{
bounds_;
image_;
map_;
div_;
constructor(bounds, image, map){
// Initialize all properties.
this.bounds_ = bounds;
this.image_ = image;
this.map_ = map;
// Define a property to hold the image's div. We'll
// actually create this div upon receipt of the onAdd()
// method so we'll leave it null for now.
this.div_ = null;
// Explicitly call setMap on this overlay.
this.setMap(map);
}
/**
* onAdd is called when the map's panes are ready and the overlay has been
* added to the map.
*/
onAdd(){
const div = document.createElement('div');
div.style.borderStyle = 'none';
div.style.borderWidth = '0px';
div.style.position = 'absolute';
// Create the img element and attach it to the div.
const img = document.createElement('img');
img.src = this.image_;
img.style.width = '100%';
img.style.height = '100%';
img.style.position = 'absolute';
div.appendChild(img);
this.div_ = div;
// Add the element to the "overlayLayer" pane.
const panes = this.getPanes();
panes.overlayLayer.appendChild(div);
};
draw(){
// We use the south-west and north-east
// coordinates of the overlay to peg it to the correct position and size.
// To do this, we need to retrieve the projection from the overlay.
const overlayProjection = this.getProjection();
// Retrieve the south-west and north-east coordinates of this overlay
// in LatLngs and convert them to pixel coordinates.
// We'll use these coordinates to resize the div.
const sw = overlayProjection.fromLatLngToDivPixel(this.bounds_.getSouthWest());
const ne = overlayProjection.fromLatLngToDivPixel(this.bounds_.getNorthEast());
// Resize the image's div to fit the indicated dimensions.
const div = this.div_;
div.style.left = sw.x + 'px';
div.style.top = ne.y + 'px';
div.style.width = (ne.x - sw.x) + 'px';
div.style.height = (sw.y - ne.y) + 'px';
};
// The onRemove() method will be called automatically from the API if
// we ever set the overlay's map property to 'null'.
onRemove(){
this.div_.parentNode.removeChild(this.div_);
this.div_ = null;
};
};
/*
/* Component Map
*/
@Component({
selector: 'map',
template: `
<div id="map"></div>
`,
styles: [
`#map{ width:100%; height:100%; position: absolute; width:100%; height:100%; top:0; left:0;}`
],
})
export class MapComponent {
overlay;
ngOnInit(){
google.maps.event.addDomListener(window, 'load', this.initMap);
}
initMap() {
const map = new google.maps.Map(document.getElementById('map'), {
zoom: 11,
center: {lat: 62.323907, lng: -150.109291},
mapTypeId: google.maps.MapTypeId.SATELLITE
});
const bounds = new google.maps.LatLngBounds(
new google.maps.LatLng(62.281819, -150.287132),
new google.maps.LatLng(62.400471, -150.005608));
// The photograph is courtesy of the U.S. Geological Survey.
const srcImage = 'https://developers.google.com/maps/documentation/' +
'javascript/examples/full/images/talkeetna.png';
// The custom USGSOverlay object contains the USGS image,
// the bounds of the image, and a reference to the map.
this.overlay = new USGSOverlay(bounds, srcImage, map);
}
}
我也遇到了很多麻烦，但最终还是解决了。至关重要的是，谷歌地图脚本是预加载的(我在我的路由解析器中加载了我的)，否则你会得到一个"谷歌"没有定义的错误。在这里查看我是如何安装类型和导入库的。
至于语法，我最终使用了一个内部类。这是因为，如果它是一个顶级类，WebPack尝试(不成功)在编译时找到google maps库:// import typings
import {} from '@types/googlemaps';
@Component({...})
export class MapComponent implements OnInit {
// weird syntax, I know, but it works
USGSOverlay = class extends google.maps.OverlayView {
constructor(bounds, image, private map){
super();
...
this.setMap(this.map);
}
onAdd(){...}
draw(){...}
}
ngOnInit() {
const overlay = new this.Overlay(bounds, image, map);
}
}
由于我的代码异步加载谷歌地图API，上述答案对我不起作用。我的问题是typescript使用谷歌变量之前加载谷歌API。
这是我找到的一个解决方案。
要查看异步地图加载器代码，请参见在组件[Angular]中加载Google Maps JS API
//map.service.ts
import { Injectable } from '@angular/core';
...
declare var google;
export let MyOverlay; // declare and use this from other ts file
@Injectable({ providedIn: 'root' })
export class MapService {
private static promise;
map: any;
public static load() {
if (!MapService.promise) {
MapService.promise = new Promise((resolve) => {
//load google api asynchronously
});
}
return MapService.promise;
}
async initMap(gmapElement, lat = -33.92, lng = 151.25) {
return MapService.load()
.then((gapi) => {
//map init
this.map = new google.maps.Map(gmapElement.nativeElement, {
//map options
})
/*** before init MyOverlay,
1. Google API should be loaded
2. AFTER MAP init(rendering), Overlay Object has Projection to calculate Overlay location
***/
this.initMyOverlay()
})
.catch(console.log)
}
initMyOverlay(){
class MyOverlayCls extends google.maps.OverlayView {
//omitted for code readability
}
MyOverlay = MyOverlayCls ; //assign class to variable
}
}
//map.component.ts
import { MapService, MyOverlay} from 'map.service';
...
@ViewChild('gmap') gmapElement: any
...
ngOnInit() {
console.log("maps init")
this.mapSvc.initMap(this.gmapElement).then(_ => {
//At this time, google API has been loaded and assigned MyOverlay as MyOverlayCls
let overlay= new MyOverlay(...)
})
在我的情况下，我不能在同一个类中有一个内部类负责加载map。我花了一些时间才弄明白怎么做。我是这样做的
export class mapTextOverlayService {
//Overlay is creatd in an inner-class because if it is at top-level class google maps library may not be available at the class load time
mapTextOverlay = class extends google.maps.OverlayView {
pos_;
text_;
map_;
div_;
constructor(pos, text, map) {
super();
// Initialize all properties.
this.pos_ = pos;
this.text_ = text;
this.map_ = map;
// Define a property to hold the text's div. We'll
// actually create this div upon receipt of the onAdd()
// method so we'll leave it null for now.
this.div_ = null;
// Explicitly call setMap on this overlay.
this.setMap(map);
}
/**
* onAdd is called when the map's panes are ready and the overlay has been
* added to the map.
*/
onAdd() {
const div = document.createElement('div');
div.style.borderStyle = 'none';
div.style.borderWidth = '0px';
div.style.position = 'absolute';
div.innerHTML = this.text_;
this.div_ = div;
// Add the element to the "overlayLayer" pane.
const panes = this.getPanes();
panes.overlayLayer.appendChild(div);
};
draw() {
// We are using bounds centre to peg it to the correct position.
// To do this, we need to retrieve the projection from the overlay.
const overlayProjection = this.getProjection();
// Convert the centre coordinates of this overlay from LatLngs to pixel coordinates.
// We'll use these coordinates to provide the dimensions of div.
const pixelPos = overlayProjection.fromLatLngToDivPixel(this.pos_);
const div = this.div_;
div.style.left = pixelPos.x + 'px';
div.style.top = pixelPos.y + 'px';
};
// The onRemove() method will be called automatically from the API if
// we ever set the overlay's map property to 'null'.
onRemove() {
this.div_.parentNode.removeChild(this.div_);
this.div_ = null;
};
onHide() {
if (this.div_) {
this.div_.style.visibility = 'hidden';
}
};
}
createMapTextOverlay(pos, text, map) {
return new this.mapTextOverlay(pos, text, map);
}
};
然后在我想要创建文本叠加的组件中:
let mtos = new mapTextOverlayService();
let label = mtos.createMapTextOverlay(boundsCenter, description, this.map.mapobject);
使用这个简单的代码创建一个自定义的覆盖。
// this.userPositionDiv is defined as variable
let overlayView = new google.maps.OverlayView();
overlayView.draw = () => {
if (!this.userPositionDiv) {
this.userPositionDiv = document.createElement('div');
this.userPositionDiv.className = 'marker';
this.userPositionDiv.style.cssText = `width: 35px; height: 35px; text-align: center; line-height: 35px; position: absolute; cursor: pointer; border-radius: 50%; color: #fff; background: #000`;
this.userPositionDiv.innerHTML = `<span class="number-id">Hello</span>`;
const panes = overlayView.getPanes();
panes.overlayImage.appendChild(this.userPositionDiv);
}
const point = this.overlayView.getProjection().fromLatLngToDivPixel(this.latLng);
if (point) {
this.userPositionDiv.style.left = (point.x - 10) + 'px';
this.userPositionDiv.style.top = (point.y - 10) + 'px';
}
}
overlayView.setMap(this.gmap);