feat(pivot): Add fieldName as non required param in PivotDimension

Author: dkamburov

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

@@ -15,6 +15,8 @@ export interface IPivotDimension {
     member: string | ((data: any) => any);
     // Enables/Disables a particular dimension from pivot structure.
     enabled: boolean;
+    // additional field name when using member as a function
+    fieldName?: string;
 }
 
 export interface IPivotValue {

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

@@ -1,5 +1,5 @@
 import { Pipe, PipeTransform } from '@angular/core';
-import { cloneArray, cloneValue } from '../../core/utils';
+import { cloneArray } from '../../core/utils';
 import { DataUtil } from '../../data-operations/data-util';
 import { FilteringExpressionsTree, IFilteringExpressionsTree } from '../../data-operations/filtering-expressions-tree';
 import { IFilteringStrategy } from '../../data-operations/filtering-strategy';
@@ -28,7 +28,7 @@ export class IgxPivotRowPipe implements PipeTransform {
         // apply aggregations based on the created groups
         PivotUtil.applyAggregations(hierarchies, values, pivotKeys);
         // generate flat data from the hierarchies
-        const data = PivotUtil.flattenHierarchy(hierarchies, collection[0] ?? [], pivotKeys);
+        const data = PivotUtil.flattenHierarchy(hierarchies, collection[0] ?? [], rows, pivotKeys);
         return data;
     }
 }

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

@@ -21,7 +21,7 @@ export class PivotUtil {
     }
 
     public static extractValueFromDimension(dim: IPivotDimension, recData: any) {
-        return typeof dim.member === 'string' ? recData[dim.member] : dim.member.call(recData);
+        return typeof dim.member === 'string' ? recData[dim.member] : dim.member.call(null, recData);
     }
 
     public static extractValuesFromDimension(dims: IPivotDimension[], recData: any){
@@ -61,21 +61,23 @@ export class PivotUtil {
         return result;
     }
 
-    public static flattenHierarchy(hierarchies, rec, pivotKeys, level = 0) {
+    public static flattenHierarchy(hierarchies, rec, dims, pivotKeys, level = 0) {
         let flatData = [];
-        const field = this.generateFieldValue(rec);
-        hierarchies.forEach((h, key) => {
-            let obj = {};
-            obj[field] = key;
-            obj[pivotKeys.records] = h[pivotKeys.records];
-            obj = {...obj, ...h[pivotKeys.aggregations]};
-            obj[pivotKeys.level] = level;
-            flatData.push(obj);
-            if (h[pivotKeys.children]) {
-                obj[pivotKeys.records] = this.flattenHierarchy(h[pivotKeys.children], rec, pivotKeys, level + 1);
-                flatData = [...flatData, ...obj[pivotKeys.records]];
-            }
-        });
+        for (const dim of dims) {
+            hierarchies.forEach((h, key) => {
+                const field = (dim && dim.fieldName) ?? this.generateFieldValue(rec);
+                let obj = {};
+                obj[field] = key;
+                obj[pivotKeys.records] = h[pivotKeys.records];
+                obj = {...obj, ...h[pivotKeys.aggregations]};
+                obj[pivotKeys.level] = level;
+                flatData.push(obj);
+                if (h[pivotKeys.children]) {
+                    obj[pivotKeys.records] = this.flattenHierarchy(h[pivotKeys.children], rec, dim.childLevels, pivotKeys, level + 1);
+                    flatData = [...flatData, ...obj[pivotKeys.records]];
+                }
+            });
+        }
 
         return flatData;
     }

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

@@ -58,6 +58,7 @@ export class PivotGridSampleComponent {
             enabled: true,
             childLevels:[
                 {
+                    fieldName: 'ProductCategory',
                     member: (data) => data.ProductCategory,
                     enabled: true,
                     childLevels:[]