Merge pull request #6408 from IgniteUI/pbozhinov/fix-6359

Fixes Hierarchical Grid's Dev Sample ExpressionChangedAfterItHasBeenCheckedError error

Author: ChronosSF

projects/igniteui-angular/src/lib/grids/hierarchical-grid/hierarchical-grid.component.ts

@@ -407,11 +407,12 @@ export class IgxHierarchicalGridComponent extends IgxHierarchicalGridBaseDirecti
     ngAfterContentInit() {
         this.updateColumnList(false);
         this.childLayoutKeys = this.parent ?
-        this.parentIsland.children.map((item) => item.key) :
-        this.childLayoutKeys = this.childLayoutList.map((item) => item.key);
+            this.parentIsland.children.map((item) => item.key) :
+            this.childLayoutKeys = this.childLayoutList.map((item) => item.key);
         this.childLayoutList.notifyOnChanges();
-        this.childLayoutList.changes.pipe(takeUntil(this.destroy$))
-        .subscribe(() => this.onRowIslandChange());
+        this.childLayoutList.changes.pipe(takeUntil(this.destroy$)).subscribe(() =>
+            this.onRowIslandChange()
+        );
         super.ngAfterContentInit();
     }
 

src/app/hierarchical-grid/hierarchical-grid.sample.ts

@@ -1,4 +1,4 @@
-import { Component, ViewChild } from '@angular/core';
+import { Component, ViewChild, ChangeDetectorRef } from '@angular/core';
 import {
     IgxRowIslandComponent,
     IgxHierarchicalGridComponent,
@@ -30,7 +30,7 @@ export class HierarchicalGridSampleComponent {
     @ViewChild('hGrid', { static: true })
     hGrid: IgxHierarchicalGridComponent;
 
-    constructor() {
+    constructor(private cdr: ChangeDetectorRef) {
         // this.localData.push({ ID: -1, Name: ''});
         // for (let i = 0; i < 10000; i++) {
         //     const prods = [];
@@ -54,6 +54,10 @@ export class HierarchicalGridSampleComponent {
         this.localData[2].childData[1].hasChild = false;
     }
 
+    ngAfterViewInit() {
+        this.cdr.detectChanges();
+    }
+
     generateData(count: number, level: number) {
         const prods = [];
         const currLevel = level;