brachi-wernick

    @HostListener('window:beforeunload', ['$event'])
    unloadNotification($event: any) {
        if (this.hasUnsavedData()) {
            $event.returnValue =true;
        }
    }

brachi-wernick

@Injectable()
export class CanDeactivateGuard implements CanDeactivate<UserFormComponent> {
  canDeactivate(component: UserFormComponent): boolean {
   
    if(component.hasUnsavedData()){
        if (confirm("You have unsaved changes! If you leave, your changes will be lost.")) {
            return true;
        } else {
            return false;
        }

brachi-wernick

{path:'user/new',component:UserFormComponent,canDeactivate: [CanDeactivateGuard]}

brachi-wernick

import {HostListener} from "@angular/core";

export abstract class ComponentCanDeactivate {
 
  abstract  canDeactivate(): boolean;



    @HostListener('window:beforeunload', ['$event'])
    unloadNotification($event: any) {

brachi-wernick

import {ComponentCanDeactivate} from '../can-deactivate/component-can-deactivate';
import {NgForm} from "@angular/forms";

export abstract class FormCanDeactivate extends ComponentCanDeactivate{

 abstract get form():NgForm;
 
 canDeactivate():boolean{
      return this.form.submitted || !this.form.dirty
  }

brachi-wernick

@Injectable()
export class CanDeactivateGuard implements CanDeactivate<ComponentCanDeactivate> {
  canDeactivate(component: ComponentCanDeactivate): boolean {
   
    if(!component.canDeactivate()){
        if (confirm("You have unsaved changes! If you leave, your changes will be lost.")) {
            return true;
        } else {
            return false;
        }

brachi-wernick

<p-listbox *ngIf="!dropdownButton"
                   [disabled]="disabled"
                   [options]="options"
                   [ngModel]="selectedItems"
                   (onChange)="onValueChange($event.value)"
                   [multiple]="true"
                   [checkbox]="true"
                   [filter]="filter"
                   [showToggleAll]="showToggleAll"
                   [metaKeySelection]="false">

brachi-wernick

@Directive({
  selector: '[requiredIf]',
   providers: [
        {provide: NG_VALIDATORS,useExisting:RequiredIfDirective, multi: true}
    ]
})
export class RequiredIfDirective implements Validator {
    @Input("requiredIf")
    requiredIf: boolean;

brachi-wernick

export interface Validator {
    validate(c: AbstractControl): ValidationErrors | null;
    registerOnValidatorChange?(fn: () => void): void;
}

brachi-wernick

 registerOnValidatorChange(fn: () => void): void { this._onChange = fn; }
 
 private _onChange: () => void;

 ngOnChanges(changes: SimpleChanges): void {
 
    if ('requiredIf' in changes) {
      
      if (this._onChange) this._onChange();
    }