fix(grid-selection):Updating the use of rowSelectionChanging event in the sample

Author: IvanKitanov17

src/app/grid/grid-sample-selection/grid-selection.component.html

@@ -52,7 +52,10 @@
 <igx-snackbar #snackbar actionText="Got it. Thanks!" (clicked)="snackbar.close()">
     <div class="container">
         <igx-icon>notification_important</igx-icon>
-        <ng-container *ngIf="selectionMode === 'multiple'">
+        <ng-container *ngIf="selectionMode === 'multiple' && selectedRowsCount!==undefined">
+            <p>Number of rows selected: {{selectedRowsCount}}</p>
+        </ng-container>
+        <ng-container *ngIf="selectionMode === 'multiple' && selectedRowsCount===undefined">
             <ul>
                 <li><b>Now you can select multiple rows within a grid.</b></li>
                 <li>Click on row selector field or press SPACE key when some cell is active to toggle row

src/app/grid/grid-sample-selection/grid-selection.component.ts

@@ -1,6 +1,6 @@
 import { Component, OnInit, ViewChild } from '@angular/core';
 
-import { IgxGridComponent, IgxSnackbarComponent } from 'igniteui-angular';
+import { IgxGridComponent, IgxSnackbarComponent, IRowSelectionEventArgs } from 'igniteui-angular';
 import { Observable } from 'rxjs';
 import { FinancialDataService } from '../../services/financial.service';
 
@@ -21,6 +21,7 @@ export class GridSelectionSampleComponent implements OnInit {
     public selectionModes = [];
     public hideRowSelectors = false;
     public selectedRows = [1, 2, 3];
+    public selectedRowsCount;
 
     constructor(private localService: FinancialDataService) {
         this.localService.getData(100000);
@@ -33,22 +34,23 @@ export class GridSelectionSampleComponent implements OnInit {
 
     }
     public ngOnInit(): void {
-        this.snackbar.autoHide = false;
+        this.snackbar.autoHide = true;
         this.snackbar.open();
     }
-
     public formatNumber(value: number) {
         return value.toFixed(2);
     }
     public formatCurrency(value: number) {
         return '$' + value.toFixed(2);
     }
-    public handleRowSelection(event) {
-        const targetCell = event.cell;
+    public handleRowSelection(event:IRowSelectionEventArgs) {
+        this.selectedRowsCount = event.newSelection.length;
+        this.snackbar.open();
     }
 
     public selectCellSelectionMode(args) {
         this.selectionMode = this.selectionModes[args.index].label;
         this.snackbar.open();
+        this.selectedRowsCount = undefined;
     }
 }