fix(scroll-view): android 'isScrollEnabled' will apply if changed while gesture is underway (#8695)

Author: CatchABus

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;
 }

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;
+    }
+}

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>

tns-core-modules-widgets/android/widgets/src/main/java/org/nativescript/widgets/HorizontalScrollView.java

@@ -70,7 +70,7 @@ public boolean onInterceptTouchEvent(MotionEvent ev) {
 
     @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;
         }
 

tns-core-modules-widgets/android/widgets/src/main/java/org/nativescript/widgets/VerticalScrollView.java

@@ -70,7 +70,7 @@ public boolean onInterceptTouchEvent(MotionEvent ev) {
 
     @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;
         }