From 02ec7f104d327df53df687ddd1b8ac5b1cdc04ba Mon Sep 17 00:00:00 2001
From: DimitrisRK <55595100+DimitrisRK@users.noreply.github.com>
Date: Tue, 7 Jul 2020 05:05:40 +0300
Subject: [PATCH] fix(scroll-view): android 'isScrollEnabled' will apply if
 changed while gesture is underway (#8695)

---
 e2e/ui-tests-app/app/scroll-view/main-page.ts |  1 +
 .../app/scroll-view/scroll-enabled-page.ts    | 25 +++++++++++++++++++
 .../app/scroll-view/scroll-enabled-page.xml   |  7 ++++++
 .../widgets/HorizontalScrollView.java         |  2 +-
 .../widgets/VerticalScrollView.java           |  2 +-
 5 files changed, 35 insertions(+), 2 deletions(-)
 create mode 100644 e2e/ui-tests-app/app/scroll-view/scroll-enabled-page.ts
 create mode 100644 e2e/ui-tests-app/app/scroll-view/scroll-enabled-page.xml

diff --git a/e2e/ui-tests-app/app/scroll-view/main-page.ts b/e2e/ui-tests-app/app/scroll-view/main-page.ts
index 6f84bec33..8089762ea 100644
--- a/e2e/ui-tests-app/app/scroll-view/main-page.ts
+++ b/e2e/ui-tests-app/app/scroll-view/main-page.ts
@@ -17,6 +17,7 @@ export function loadExamples() {
     examples.set("safe-area-images", "scroll-view/safe-area-images-page");
     examples.set("safe-area-images-overflow", "scroll-view/safe-area-images-overflow-page");
     examples.set("layout-outside-scroll", "scroll-view/layout-outside-scroll-page");
+    examples.set("scroll-enabled", "scroll-view/scroll-enabled-page");
 
     return examples;
 }
diff --git a/e2e/ui-tests-app/app/scroll-view/scroll-enabled-page.ts b/e2e/ui-tests-app/app/scroll-view/scroll-enabled-page.ts
new file mode 100644
index 000000000..4be65ab52
--- /dev/null
+++ b/e2e/ui-tests-app/app/scroll-view/scroll-enabled-page.ts
@@ -0,0 +1,25 @@
+import { EventData as ObservableEventData } from "tns-core-modules/data/observable";
+import { GestureStateTypes, PanGestureEventData } from "tns-core-modules/ui/gestures";
+import { Page } from "tns-core-modules/ui/page";
+
+export function pageLoaded(args: ObservableEventData) {
+    var page = <Page>args.object;
+}
+
+export function panLayout(args: PanGestureEventData)
+{
+    const scrollView = args.object.parent;
+
+    if (args.state === GestureStateTypes.began) {
+        args.object.previousDeltaY = 0;
+        scrollView.isScrollEnabled = false;
+    }
+    else if (args.state === GestureStateTypes.changed) {
+        const diff = (args.deltaY - args.object.previousDeltaY);
+        args.object.translateY += diff;
+        args.object.previousDeltaY = args.deltaY;
+    }
+    else if (args.state === GestureStateTypes.ended) {
+        scrollView.isScrollEnabled = true;
+    }
+}
diff --git a/e2e/ui-tests-app/app/scroll-view/scroll-enabled-page.xml b/e2e/ui-tests-app/app/scroll-view/scroll-enabled-page.xml
new file mode 100644
index 000000000..ee85aac1d
--- /dev/null
+++ b/e2e/ui-tests-app/app/scroll-view/scroll-enabled-page.xml
@@ -0,0 +1,7 @@
+<Page xmlns="http://schemas.nativescript.org/tns.xsd" loaded="pageLoaded" class="page">
+    <ScrollView id="scroll-view" height="300">
+        <StackLayout height="500" backgroundColor="red" pan="panLayout">
+            <Label text="Move Me" color="#fff" fontSize="22"/>
+        </StackLayout>
+    </ScrollView>
+</Page>
diff --git a/tns-core-modules-widgets/android/widgets/src/main/java/org/nativescript/widgets/HorizontalScrollView.java b/tns-core-modules-widgets/android/widgets/src/main/java/org/nativescript/widgets/HorizontalScrollView.java
index c63489719..af8a05125 100644
--- a/tns-core-modules-widgets/android/widgets/src/main/java/org/nativescript/widgets/HorizontalScrollView.java
+++ b/tns-core-modules-widgets/android/widgets/src/main/java/org/nativescript/widgets/HorizontalScrollView.java
@@ -70,7 +70,7 @@ public class HorizontalScrollView extends android.widget.HorizontalScrollView {
 
     @Override
     public boolean onTouchEvent(MotionEvent ev) {
-        if (!this.scrollEnabled && ev.getAction() == MotionEvent.ACTION_DOWN) {
+        if (!this.scrollEnabled && (ev.getAction() == MotionEvent.ACTION_DOWN || ev.getAction() == MotionEvent.ACTION_MOVE)) {
             return false;
         }
 
diff --git a/tns-core-modules-widgets/android/widgets/src/main/java/org/nativescript/widgets/VerticalScrollView.java b/tns-core-modules-widgets/android/widgets/src/main/java/org/nativescript/widgets/VerticalScrollView.java
index db109467c..23144c2d9 100644
--- a/tns-core-modules-widgets/android/widgets/src/main/java/org/nativescript/widgets/VerticalScrollView.java
+++ b/tns-core-modules-widgets/android/widgets/src/main/java/org/nativescript/widgets/VerticalScrollView.java
@@ -70,7 +70,7 @@ public class VerticalScrollView extends ScrollView {
 
     @Override
     public boolean onTouchEvent(MotionEvent ev) {
-        if (!this.scrollEnabled && ev.getAction() == MotionEvent.ACTION_DOWN) {
+        if (!this.scrollEnabled && (ev.getAction() == MotionEvent.ACTION_DOWN || ev.getAction() == MotionEvent.ACTION_MOVE)) {
             return false;
         }