Fixed #2108 - Extend TreeNode API with expandedIcon & collapsedIcon

src/components/tree/TreeNode.vue

@@ -273,10 +273,7 @@ export default {
             return ['p-treenode-icon', this.node.icon];
         },
         toggleIcon() {
-            return ['p-tree-toggler-icon pi pi-fw', {
-                'pi-chevron-down': this.expanded,
-                'pi-chevron-right': !this.expanded
-            }];
+            return ['p-tree-toggler-icon pi pi-fw', this.expanded ? this.node.expandedIcon || 'pi-chevron-down' : this.node.collapsedIcon || 'pi-chevron-right'];
         },
         checkboxClass() {
             return ['p-checkbox-box', {'p-highlight': this.checked, 'p-indeterminate': this.partialChecked}];

src/views/tree/TreeDoc.vue

@@ -57,6 +57,18 @@ import Tree from 'primevue/tree';
                         <td>null</td>
                         <td>Icon of the node to display next to content.</td>
                     </tr>
+                    <tr>
+                        <td>expandedIcon</td>
+                        <td>string</td>
+                        <td>null</td>
+                        <td>Icon to use in expanded state.</td>
+                    </tr>
+                    <tr>
+                        <td>collapsedIcon</td>
+                        <td>string</td>
+                        <td>null</td>
+                        <td>Icon to use in collapsed state.</td>
+                    </tr>
                     <tr>
                         <td>children</td>
                         <td>TreeNode[]</td>