[ADF-2765] Fix for the gallery view in datatable component (#3470)

* [ADF-2765] Fix for the gallery view in datatable component

* [ADF-2765] Fixed lint errors

* [ADF-2765] Changed maximum columns per row number

* [ADF-2765] Removed trailing whitespace

lib/core/datatable/components/datatable/datatable.component.ts

@@ -161,6 +161,9 @@ export class DataTableComponent implements AfterContentInit, OnChanges, DoCheck,
     isSelectAllChecked: boolean = false;
     selection = new Array<DataRow>();
 
+    /** This array of fake rows fix the flex layout for the gallery view */
+    fakeRows = [];
+
     private clickObserver: Observer<DataRowEvent>;
     private click$: Observable<DataRowEvent>;
 
@@ -188,6 +191,7 @@ export class DataTableComponent implements AfterContentInit, OnChanges, DoCheck,
                 })
             );
         }
+        this.datatableLayoutFix();
         this.setTableSchema();
     }
 
@@ -220,6 +224,10 @@ export class DataTableComponent implements AfterContentInit, OnChanges, DoCheck,
         if (this.isPropertyChanged(changes['sorting'])) {
             this.setTableSorting(changes['sorting'].currentValue);
         }
+
+        if (this.isPropertyChanged(changes['display'])) {
+            this.datatableLayoutFix();
+        }
     }
 
     ngDoCheck() {
@@ -654,4 +662,16 @@ export class DataTableComponent implements AfterContentInit, OnChanges, DoCheck,
             this.dataRowsChanged = null;
         }
     }
+
+    datatableLayoutFix() {
+        const maxGalleryRows = 25;
+
+        if (this.display === 'gallery') {
+            for (let i = 0; i < maxGalleryRows; i++) {
+               this.fakeRows.push('');
+            }
+        } else {
+            this.fakeRows = [];
+        }
+    }
 }