Fixed #3303

src/app/components/panelmenu/panelmenu.ts

@@ -123,22 +123,27 @@ export class PanelMenu extends BasePanelMenuItem {
 
     @Input() styleClass: string;
 
-    @Input() hasSingleItemExpanded: boolean = false;
+    @Input() multiple: boolean = true;
 
     public animating: boolean;
 
     collapseAll() {
-    	for( let item of this.model ) {
+    	for(let item of this.model) {
     		if(item.expanded) {
     			item.expanded = false;
     		}
     	}
     }
 
     handleClick(event, item) {
-    	if(this.hasSingleItemExpanded) {
-    		this.collapseAll();
+    	if(!this.multiple) {
+            for(let modelItem of this.model) {
+        		if(item !== modelItem && modelItem.expanded) {
+        			modelItem.expanded = false;
+        		}
+        	}
     	}
+
         this.animating = true;
         super.handleClick(event, item);
     }

src/app/showcase/components/panelmenu/panelmenudemo.html

@@ -6,7 +6,7 @@
 </div>
 
 <div class="content-section implementation">
-    <p-panelMenu [model]="items" [style]="&#123;'width':'300px'&#125;"></p-panelMenu>
+    <p-panelMenu [model]="items" [style]="{'width':'300px'}" [multiple]="false"></p-panelMenu>
 </div>
 
 <div class="content-section documentation">
@@ -147,10 +147,10 @@ <h3>Properties</h3>
                             <td>Style class of the component.</td>
                         </tr>
                         <tr>
-                            <td>hasSingleItemExpanded</td>
+                            <td>multiple</td>
                             <td>boolean</td>
-                            <td>false</td>
-                            <td>Flag to expand only single menu item.</td>
+                            <td>true</td>
+                            <td>Whether multiple tabs can be activated at the same time or not.</td>
                         </tr>
                     </tbody>
                 </table>