mapInstance is undefined while trying to remove

[mloffer]

While quickly switching between two mgl-map instances, a hook to destroy the instance is scheduled, but the reference is undefined when called.

app.component.html:

<div [ngSwitch]="whichMap">
	<mgl-map *ngSwitchCase="'first'"></mgl-map>
	<mgl-map *ngSwitchCase="'second'"></mgl-map>
</div>

app.component.ts:

export class AppComponent implements OnInit {
	whichMap = 'first';

	ngOnInit() {
		// Change which map we're displaying after the current synchronous code runs
		Promise.resolve(null).then(() => this.whichMap = 'second');
	}
}

ERROR TypeError: Cannot read property 'remove' of undefined
    at MapService.push../node_modules/ngx-mapbox-gl/fesm5/ngx-mapbox-gl.js.MapService.destroyMap (ngx-mapbox-gl.js:83)
    at MapComponent.push../node_modules/ngx-mapbox-gl/fesm5/ngx-mapbox-gl.js.MapComponent.ngOnDestroy (ngx-mapbox-gl.js:3324)

Only one MapComponent constructor gets run in this scenario, so I'm unclear on why MapComponent.ngOnDestroy gets called at all.

This seems to be resolved by performing a safety check before attempting to call mapInstance.remove(). See pull request #141.

[Wykks]

Yep indeed. ngOnDestroy can be called, even if ngOnInit hasn't been called 👍