fix(igxGrid): Fix when grid and cols have % width in hidden container.

projects/igniteui-angular/src/lib/grids/columns/column.component.ts

@@ -2527,7 +2527,9 @@ export class IgxColumnComponent implements AfterContentInit, OnDestroy, ColumnTy
         const colWidth = this.width;
         const isPercentageWidth = colWidth && typeof colWidth === 'string' && colWidth.indexOf('%') !== -1;
         const isAutoWidth = colWidth && typeof colWidth === 'string' && colWidth === 'fit-content';
-        if (isPercentageWidth) {
+        if (isPercentageWidth && this.grid.isColumnWidthSum) {
+            this._calcWidth = this.grid.minColumnWidth;
+        } else if (isPercentageWidth ) {
             this._calcWidth = Math.floor(parseFloat(colWidth) / 100 * this.grid.calcWidth);
         } else if (!colWidth || isAutoWidth && !this.autoSize) {
             // no width

projects/igniteui-angular/src/lib/grids/common/grid.interface.ts

@@ -718,7 +718,10 @@ export interface GridType extends IGridDataBindable {
     isLoading: boolean;
     /** @hidden @internal */
     gridSize: Size;
-
+    /** @hidden @internal */
+    isColumnWidthSum: boolean;
+    /** @hidden @internal */
+    minColumnWidth: number;
     /** Strategy, used for cloning the provided data. The type has one method, that takes any type of data */
     dataCloneStrategy: IDataCloneStrategy;
 

projects/igniteui-angular/src/lib/grids/grid-base.directive.ts

@@ -3001,6 +3001,12 @@ export abstract class IgxGridBaseDirective implements GridType,
      * @hidden @internal
      */
     public filteringPipeTrigger = 0;
+
+    /**
+     * @hidden @internal
+     */
+    public isColumnWidthSum = false;
+
     /**
      * @hidden @internal
      */
@@ -3201,7 +3207,7 @@ export abstract class IgxGridBaseDirective implements GridType,
     private _columnSelectionMode: GridSelectionMode = GridSelectionMode.none;
 
     private lastAddedRowIndex;
-    protected isColumnWidthSum = false;
+
     private _currencyPositionLeft: boolean;
 
     private rowEditPositioningStrategy = new RowEditPositionStrategy({
@@ -3234,7 +3240,7 @@ export abstract class IgxGridBaseDirective implements GridType,
     /**
      * @hidden @internal
      */
-    protected get minColumnWidth() {
+    public get minColumnWidth() {
         return MINIMUM_COLUMN_WIDTH;
     }
 
@@ -6488,8 +6494,10 @@ export abstract class IgxGridBaseDirective implements GridType,
 
 
         if (this.width === null || !width) {
-            width = this.getColumnWidthSum();
             this.isColumnWidthSum = true;
+            width = this.getColumnWidthSum();
+        } else {
+            this.isColumnWidthSum = false;
         }
 
         if (this.hasVerticalScroll() && this.width !== null) {

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

@@ -1870,6 +1870,21 @@ describe('IgxGrid Component Tests #grid', () => {
             expect(parseInt(grid.hostWidth, 10)).toBe(30 * 136);
         });
 
+        it('should render grid and columns with correct width when all are in % and inside a hidden container.', () => {
+            // in this case since the grid width is 0, the grid will use the sum of the columns
+            // those should resolve to 136px, as per the docs
+            const fix = TestBed.createComponent(IgxGridColumnHiddenPercentageWidthComponent);
+            const grid = fix.componentInstance.grid;
+            grid.width = '100%';
+            // 4 cols - 10% width
+            fix.componentInstance.initColumnsRows(5, 4);
+            fix.detectChanges();
+
+            expect(grid.calcWidth).toBe(136*4);
+            expect(grid.columns[0].calcWidth).toBe(136);
+            expect(grid.columns[1].calcWidth).toBe(136);
+        });
+
         it('should retain column with in % after hiding/showing grid with 100% width', () => {
             const fix = TestBed.createComponent(IgxGridColumnPercentageWidthComponent);
             fix.componentInstance.initColumnsRows(5, 3);
@@ -3100,6 +3115,18 @@ export class IgxGridColumnPercentageWidthComponent extends IgxGridDefaultRenderi
     }
 }
 
+@Component({
+    template: `<igx-grid #grid [hidden]="hidden" [data]="data" [autoGenerate]="false">
+        <igx-column *ngFor="let col of columns" [width]="'10%'" [field]="col.key" [header]="col.key" [dataType]="col.dataType">
+        </igx-column>
+    </igx-grid>`,
+    standalone: true,
+    imports: [IgxGridComponent, IgxColumnComponent, NgFor]
+})
+export class IgxGridColumnHiddenPercentageWidthComponent extends IgxGridDefaultRenderingComponent {
+    public hidden = true;
+}
+
 @Component({
     template: `<div>
         <igx-grid #grid [data]="data" height='300px' [style.--ig-size]="1" [autoGenerate]="true"

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

@@ -479,7 +479,7 @@ export class IgxPivotGridComponent extends IgxGridBaseDirective implements OnIni
     /**
      * @hidden @internal
      */
-    protected override get minColumnWidth() {
+    public override get minColumnWidth() {
         if (this.superCompactMode) {
             return MINIMUM_COLUMN_WIDTH_SUPER_COMPACT;
         } else {