improve actions on selected rows

.vscode/settings.json

+{
+    "makefile.extensionOutputFolder": "./.vscode"
+}
\ No newline at end of file

Makefile

-UID := 1000
-GID := 1000
+UID := 9898
+GID := 4000
 
 list:
 	@echo ""

client/src/app/instance/search/components/result/datatable-actions.component.html

 <div *ngIf="dataset.datatable_selectable_rows" class="btn-group mb-2" dropdown [isDisabled]="selectedData.length < 1">
-    <button id="button-basic" dropdownToggle type="button" class="btn btn-primary dropdown-toggle" aria-controls="dropdown-basic">
-        Actions <span class="caret"></span>
+    <button id="button-basic" dropdownToggle type="button" class="btn btn-primary dropdown-toggle"
+        aria-controls="dropdown-basic">
+        <span *ngIf="!selectedData.length">Actions on selected rows (select rows first)</span>
+        <span *ngIf="selectedData.length">Actions on {{selectedData.length}} rows </span>
+        <span class="caret"></span>
     </button>
     <ul id="dropdown-basic" *dropdownMenu class="dropdown-menu" role="menu" aria-labelledby="button-basic">
         <li *ngIf="dataset.download_json" role="menuitem">
-            <a class="dropdown-item" [href]="getDatatableUrl('json')" (click)="download($event, getDatatableUrl('json'), 'json')">
+            <a class="dropdown-item" [href]="getDatatableUrl('json')"
+                (click)="download($event, getDatatableUrl('json'), 'json')">
                 <span class="fas fa-file"></span> Download JSON
             </a>
         </li>
         <li *ngIf="dataset.download_csv" role="menuitem">
-            <a class="dropdown-item" [href]="getDatatableUrl('csv')" (click)="download($event, getDatatableUrl('csv'), 'csv')">
+            <a class="dropdown-item" [href]="getDatatableUrl('csv')"
+                (click)="download($event, getDatatableUrl('csv'), 'csv')">
                 <span class="fas fa-file-csv"></span> Download CSV
             </a>
         </li>
         <li *ngIf="dataset.download_ascii" role="menuitem">
-            <a class="dropdown-item" [href]="getDatatableUrl('ascii')" (click)="download($event, getDatatableUrl('ascii'), 'ascii')">
+            <a class="dropdown-item" [href]="getDatatableUrl('ascii')"
+                (click)="download($event, getDatatableUrl('ascii'), 'ascii')">
                 <span class="fas fa-file"></span> Download ASCII
             </a>
         </li>
         <li *ngIf="dataset.download_vo" role="menuitem">
-            <a class="dropdown-item" [href]="getDatatableUrl('votable')" (click)="download($event, getDatatableUrl('votable'), 'votable')">
+            <a class="dropdown-item" [href]="getDatatableUrl('votable')"
+                (click)="download($event, getDatatableUrl('votable'), 'votable')">
                 <span class="fas fa-file"></span> VOtable
             </a>
         </li>
@@ -34,4 +41,4 @@
             </a>
         </li>
     </ul>
-</div>
+</div>
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