Added documentation for selectedIndexChanged event.

Nedyalko Nikolov · Nedyalko Nikolov · commit c991cd7ed059 · 2016-07-22T16:13:43.000+03:00
diff --git a/tests/app/ui/tab-view/tab-view-tests.ts b/tests/app/ui/tab-view/tab-view-tests.ts
@@ -231,10 +231,12 @@ export class TabViewTest extends testModule.UITest<tabViewModule.TabView> {
             return tabView.selectedIndex === expectedOldIndex;
         }, helper.ASYNC);
 
+        // >> article-tabview-selectedIndexChanged
         tabView.on(tabViewModule.TabView.selectedIndexChangedEvent, (args: tabViewModule.SelectedIndexChangedEventData) => {
             actualOldIndex = args.oldIndex;
             actualNewIndex = args.newIndex;
         });
+        // << article-tabview-selectedIndexChanged
 
         tabViewTestsNative.selectNativeTab(tabView, expectedNewIndex);
         TKUnit.waitUntilReady(function () {
diff --git a/tests/app/ui/tab-view/tab-view.md b/tests/app/ui/tab-view/tab-view.md
@@ -33,3 +33,17 @@ Using a TabView requires the "ui/tab-view" module.
 {%snippet article-select-tab%}
 ## Creating a TabView
 {%snippet article-create-tabview%}
+### Using selectedIndexChanged changed event
+{%snippet article-tabview-selectedIndexChanged%}
+### Using selectedIndexChanged event from xml
+```XML
+<Page>
+ <TabView selectedIndexChanged="onSelectedIndexChanged">
+   ...
+ </TabView>
+</Page>
+```
+```TypeScript
+export function onSelectedIndexChanged(args) {...}
+```
+> Note: Initially selectedIndexChanged event will be raised just after adding a new items to TabView without any user interaction, which will happen on TabView loaded. SelectedIndexChanged event will be raised because value of the selectedIndex property is changed from undefined (default) (with no items) to 0 (first tab item). Depends on how TabView.items are set or added it may happen to raise one or two times selectedIndexChanged event even before page events (loaded, navigatingTo, navigatedTo, ...).
