From f1abec42b5404ee5afc100957689de7430fb4e60 Mon Sep 17 00:00:00 2001
From: Vladimir Enchev <vladimir.enchev@telerik.com>
Date: Tue, 10 Nov 2015 15:20:21 +0200
Subject: [PATCH] more code + tests updates

---
 .../tests/ui/scroll-view/scroll-view-tests.ts | 52 ++++++++++++++++++-
 ui/scroll-view/scroll-view-common.ts          | 14 +++--
 2 files changed, 56 insertions(+), 10 deletions(-)

diff --git a/apps/tests/ui/scroll-view/scroll-view-tests.ts b/apps/tests/ui/scroll-view/scroll-view-tests.ts
index 3446ac9fb..ccd0e7407 100644
--- a/apps/tests/ui/scroll-view/scroll-view-tests.ts
+++ b/apps/tests/ui/scroll-view/scroll-view-tests.ts
@@ -285,7 +285,7 @@ class ScrollLayoutTest extends testModule.UITest<scrollViewModule.ScrollView> {
 
         this.testView.scrollToVerticalOffset(100, false);
         TKUnit.waitUntilReady(function () { return scrollY > 0; });
-        TKUnit.assertEqual(this.testView.verticalOffset, scrollY);
+        TKUnit.assertEqual(scrollY, this.testView.verticalOffset);
     }
 
     public test_scrollView_horizontal_raised_scroll_event() {
@@ -307,7 +307,55 @@ class ScrollLayoutTest extends testModule.UITest<scrollViewModule.ScrollView> {
 
         this.testView.scrollToHorizontalOffset(100, false);
         TKUnit.waitUntilReady(function () { return scrollX > 0; });
-        TKUnit.assertEqual(this.testView.horizontalOffset, scrollX);
+        TKUnit.assertEqual(scrollX, this.testView.horizontalOffset);
+    }
+
+    public test_scrollView_vertical_raised_scroll_event_after_loaded() {
+        this.testView.orientation = enums.Orientation.vertical;
+
+        this.waitUntilTestElementIsLoaded();
+
+        var scrollY: number;
+        this.testView.on(scrollViewModule.ScrollView.scrollEvent, (args: scrollViewModule.ScrollEventData) => {
+            scrollY = args.scrollY;
+        });
+
+        this.testView.width = 200;
+        this.testView.height = 300;
+
+        var btn = new button.Button();
+        btn.text = "test";
+        btn.height = 500;
+        this.testView.content = btn;
+        this.waitUntilTestElementLayoutIsValid();
+
+        this.testView.scrollToVerticalOffset(100, false);
+        TKUnit.waitUntilReady(function () { return scrollY > 0; });
+        TKUnit.assertEqual(scrollY, this.testView.verticalOffset);
+    }
+
+    public test_scrollView_horizontal_raised_scroll_event_after_loaded() {
+        this.testView.orientation = enums.Orientation.horizontal;
+
+        this.waitUntilTestElementIsLoaded();
+
+        var scrollX: number;
+        this.testView.on(scrollViewModule.ScrollView.scrollEvent, (args: scrollViewModule.ScrollEventData) => {
+            scrollX = args.scrollX;
+        });
+
+        this.testView.width = 200;
+        this.testView.height = 300;
+
+        var btn = new button.Button();
+        btn.text = "test";
+        btn.width = 500;
+        this.testView.content = btn;
+        this.waitUntilTestElementLayoutIsValid();
+
+        this.testView.scrollToHorizontalOffset(100, false);
+        TKUnit.waitUntilReady(function () { return scrollX > 0; });
+        TKUnit.assertEqual(scrollX, this.testView.horizontalOffset);
     }
 }
 
diff --git a/ui/scroll-view/scroll-view-common.ts b/ui/scroll-view/scroll-view-common.ts
index 9d0836cca..f9074e34a 100644
--- a/ui/scroll-view/scroll-view-common.ts
+++ b/ui/scroll-view/scroll-view-common.ts
@@ -18,7 +18,7 @@ export var orientationProperty = new dependencyObservable.Property(
 );
 
 export class ScrollView extends contentView.ContentView implements definition.ScrollView {
-    private _scrollEventAttached: boolean;
+    private _scrollChangeCount: number = 0;
     public static scrollEvent = "scroll";
 
     get orientation(): string {
@@ -32,6 +32,7 @@ export class ScrollView extends contentView.ContentView implements definition.Sc
         super.addEventListener(arg, callback, thisArg);
 
         if (arg === definition.ScrollView.scrollEvent) {
+            this._scrollChangeCount++;
             this.attach();
         }
     }
@@ -40,6 +41,7 @@ export class ScrollView extends contentView.ContentView implements definition.Sc
         super.addEventListener(arg, callback, thisArg);
 
         if (arg === definition.ScrollView.scrollEvent) {
+            this._scrollChangeCount--;
             this.dettach();
         }
     }
@@ -57,23 +59,19 @@ export class ScrollView extends contentView.ContentView implements definition.Sc
     }
 
     private attach() {
-        if (!this._scrollEventAttached && this.isLoaded) {
-            this._scrollEventAttached = true;
-
+        if (this._scrollChangeCount > 0 && this.isLoaded) {
             this.attachNative();
         }
     }
 
     private dettach() {
-        if (this._scrollEventAttached && this.isLoaded) {
-            this._scrollEventAttached = false;
-
+        if (this._scrollChangeCount === 0 && this.isLoaded) {
             this.dettachNative();
         }
     }
 
     protected attachNative() {
-       //
+        //
     }
 
     protected dettachNative() {