Updated: 19/03/2017 this.form.controls[‘dept’].setValue(selected.id); OLD: For now we are forced to do a type cast: (<Control>this.form.controls[‘dept’]).updateValue(selected.id) Not very elegant I agree. Hope this gets improved in future versions.
For each sort graph you need some kind of model, which should hold the current state of each sort. This would probably mean adding your list of ints to a separate list per sort. You would also need some kind of mechanism that would allow you to loop through each sort algorithm and tell it … Read more
Register the EventEmitter in your child component as the @Output: @Output() onDatePicked = new EventEmitter<any>(); Emit value on click: public pickDate(date: any): void { this.onDatePicked.emit(date); } Listen for the events in your parent component’s template: <div> <calendar (onDatePicked)=”doSomething($event)”></calendar> </div> and in the parent component: public doSomething(date: any):void { console.log(‘Picked date: ‘, date); } It’s also … Read more
Run change detection explicitly after the change: import { ChangeDetectorRef } from ‘@angular/core’; constructor(private cdRef:ChangeDetectorRef) {} ngAfterViewChecked() { console.log( “! changement de la date du composant !” ); this.dateNow = new Date(); this.cdRef.detectChanges(); }
If you are providing your DataService inside the providers array of your @Component annotation, @Component({ … providers: [DataService], })… this service will be a singleton (it will create a new instance) for this component (and it’s children if they have not provided this service under their annotation also). If you want to use this service … Read more
You could leverage a ReplaySubject for that: EDIT: Different since RxJS 6.x: Note the use of the pipe() method. class myComponent { private destroyed$: ReplaySubject<boolean> = new ReplaySubject(1); constructor( private serviceA: ServiceA, private serviceB: ServiceB, private serviceC: ServiceC) {} ngOnInit() { this.serviceA .pipe(takeUntil(this.destroyed$)) .subscribe(…); this.serviceB .pipe(takeUntil(this.destroyed$)) .subscribe(…); this.serviceC .pipe(takeUntil(this.destroyed$)) .subscribe(…); } ngOnDestroy() { this.destroyed$.next(true); this.destroyed$.complete(); … Read more
2022 Update You only need a class component when you: need to create an error boundary using componentDidCatch Original 2016 Answer You only need a class component when you: need the component state or need the lifecycle methods. such as componentDidMount etc.
update forwardRef() isn’t required anymore because directives was moved to NgModule.declarations and therefore recursive components don’t need to be registered on themselves as directives anymore. Angular 4.x.x Plunker example original That supported. You just need to add the component to directives: [] in its @Component() decorator. Because the decorator comes before the class and classes … Read more
Update for 10.4 Delphi 10.4 Sydney unified memory management across all platforms and removed ARC compiler. In other words, all platforms now follow the same memory management rules as the Windows platform. DisposeOf vs Free in classic (non ARC) compiler DisposeOf on classic compiler calls Free and functionally behaves the same DisposeOf is left for … Read more
Generally speaking, extending the component tends to be done strictly to use the component. This severely limits your options in unnecessary ways in terms of design, so that your classes can’t extend different classes, you can’t hide the JFrame’s methods causing it to be more difficult to maintain and easier to trigger unexpected bugs when … Read more