NGX-Leaflet-Loading

This is a wrapper for the leaflet.loading control to make it easy to use in Angular 8+.

This wrapper is tested against the @asymmetrik/ngx-leaflet library but it has no dependency on that library so should work without it. It does, obviously, have a dependency that leaflet is loaded.

For more detailed descriptions of how this wrapper was created : Documentation.

For detailed descriptions of how to use and worked examples : Article, Article

For an example of this working in a real site - see trackbash.

Install

Install using npm:

npm install @runette/ngx-leaflet-loading

Note that from version 1.0.4, this library is built using a partial Ivy compilation and should work with any version of Angular.io after version 12.0.0

Usage

This library needs to be imported into the application module:

import {NgxLoadingControlModule} from '@runette/ngx-leaflet-loading'

imports: [
    ...
    NgxLoadingControlModule,
  ],

Then, the control is inserted using the following directive:

<leaflet-loading-control
    [map]='...'
    [options]="..."
></leaflet-loading-control>

Where map is an instance of a leaflet map and options is an object with valid options for the control.

Usage with NGX-Leaflet

This library integrates very easily with ngx-leaflet using the onMapReady event:

<div id='map' class="map-container" leaflet
     [leafletOptions]="options"
     (leafletMapReady)="onMapReady($event)"
     ></div>
<leaflet-loading-control
    [map]='map'
    [options]="loadingOptions"
></leaflet-loading-control>

by adding the following to your map component:

...
import { Map, LoadingOptions } from 'leaflet';


export class OsmMapComponent implements OnInit, OnDestroy {
  public map?: Map;
  public loadingOptions: LoadingOptions={
    position: 'topleft',
  }
  
  ...
  
  onMapReady(map: Map) {
    this.map = map;
  }

Usage - CSS

Unfortunately - I think because the leaflet map is run outside of Angular by ngx-leaflet - the normal css encapsulation does not work and you have to load the css globally.

Add the following to the styles.css

@import "leaflet-loading/src/Control.Loading.css";

Build Config

For some reason yet to be found - this library does not like being built with "buildOptimizer": true, in the build environment - which is usually the default for the production environment in angular.json.

Always build with "buildOptimizer": false,.

API Access to the Control

If you want access the control's methods directly from your typescript code - this can be done with @ViewChild

Use ViewChild to access the component, for instance

@ViewChild(NgxLoadingControlComponent,{static: false}) loadingComponent: NgxLoadingControlComponent;

The actual instance of the control can then be accessed directly as this.loadingComponent.loading

For more details and worked examples, see : Article

Contributions

Contributions to this repository are very welcome.

Please fork the repository and create a new branch for your changes. The branch can be built locally using

ng build ngx-leaflet-loading

in the root folder of the repo. This creates an npm package in a folder called dist. This can loaded in a test app using npm install and the FQ path to the dist folder.

When your changes are complete create a Pull Requet against the master. It is IMPORTANT that you change the version number in package.json AND the tag number in .github/workflowds/build.yaml to the next version before the PR.

When I have accepted and merged the PR, Github actions will automatically build the new package release and loaded it both as a GH release using the version as the tag name and publish the new version on npm.