fix(igx-grid): Change checks for moving left/right, #4412 (#4417)

Author: sstoyanovIG

projects/igniteui-angular/src/lib/grids/filtering/excel-style/excel-style-column-moving.component.ts

@@ -26,16 +26,14 @@ export class IgxExcelStyleColumnMovingComponent {
     }
 
     get canNotMoveLeft() {
-        const prevIndex = this.grid.columns.indexOf(this.column) - 1;
         return this.column.visibleIndex === 0 ||
             (this.grid.unpinnedColumns.indexOf(this.column) === 0 && this.column.disablePinning) ||
-            (this.column.level !== 0 && this.grid.columns[prevIndex] && this.grid.columns[prevIndex].level !== this.column.level);
+            (this.column.level !== 0 && !this.findColumn(0, this.visibleColumns));
     }
 
     get canNotMoveRight() {
-        const nextIndex = this.grid.columns.indexOf(this.column) + 1;
         return this.column.visibleIndex === this.visibleColumns.length - 1 ||
-            (this.column.level !== 0 && this.grid.columns[nextIndex] && this.grid.columns[nextIndex].level !== this.column.level);
+            (this.column.level !== 0 && !this.findColumn(1, this.visibleColumns));
     }
 
     public onMoveButtonClicked(moveDirection) {
@@ -66,7 +64,12 @@ export class IgxExcelStyleColumnMovingComponent {
                 }
             }
         } else {
-            return columns[index + 1];
+            while (index < columns.length - 1) {
+                index++;
+                if (columns[index].level === this.column.level && columns[index].parent === this.column.parent) {
+                    return columns[index];
+                }
+            }
         }
     }
 }