chore(*): when rowEditTabs are null move to first/last editable cell

Author: nrobakova

projects/igniteui-angular/src/lib/grids/grid-navigation.service.ts

@@ -167,23 +167,34 @@ export class IgxGridNavigationService {
     }
 
     public movePreviousEditable(rowIndex: number, currentColumnVisibleIndex: number) {
-        const prevEditableColumnIndex = this.findNextEditable(MoveDirection.LEFT, currentColumnVisibleIndex - 1);
+        let prevEditableColumnIndex = this.findNextEditable(MoveDirection.LEFT, currentColumnVisibleIndex - 1);
         if (prevEditableColumnIndex === -1) {
-            //  TODO: make gridAPI visible for internal use and remove cast to any
-            (this.grid as any).gridAPI.submit_value();
-            if (this.grid.rowEditTabs.length) { this.grid.rowEditTabs.last.element.nativeElement.focus(); }
-            return;
+            if (this.grid.rowEditTabs.length) {
+                //  TODO: make gridAPI visible for internal use and remove cast to any
+                (this.grid as any).gridAPI.submit_value();
+                this.grid.rowEditTabs.last.element.nativeElement.focus();
+                return;
+            } else {
+                // In case when row edit template is empty select last editable cell
+                prevEditableColumnIndex = this.grid.lastEditableColumnIndex;
+            }
+
         }
         this.focusEditableTarget(rowIndex, prevEditableColumnIndex);
     }
 
     public moveNextEditable(rowIndex: number, currentColumnVisibleIndex: number) {
-        const nextEditableColumnIndex = this.findNextEditable(MoveDirection.RIGHT, currentColumnVisibleIndex + 1);
+        let nextEditableColumnIndex = this.findNextEditable(MoveDirection.RIGHT, currentColumnVisibleIndex + 1);
         if (nextEditableColumnIndex === -1) {
-            //  TODO: make gridAPI visible for internal use and remove cast to any
-            (this.grid as any).gridAPI.submit_value();
-            if ( this.grid.rowEditTabs.length) { this.grid.rowEditTabs.first.element.nativeElement.focus(); }
-            return;
+            if ( this.grid.rowEditTabs.length) {
+                 //  TODO: make gridAPI visible for internal use and remove cast to any
+                (this.grid as any).gridAPI.submit_value();
+                this.grid.rowEditTabs.first.element.nativeElement.focus();
+                return;
+            } else {
+                // In case when row edit template is empty select first editable cell
+                nextEditableColumnIndex = this.grid.firstEditableColumnIndex;
+            }
         }
         this.focusEditableTarget(rowIndex, nextEditableColumnIndex);
     }