From 9e9bbefada450630f7a5c42fc4216fdd2f071bf4 Mon Sep 17 00:00:00 2001
From: Kacper Wiszczuk <kacperwiszczuk@gmail.com>
Date: Sat, 22 Sep 2018 12:49:14 +0200
Subject: [PATCH] Changed react-native event handler types

---
 types/react-native/index.d.ts     | 15 ++++++++-------
 types/react-native/test/index.tsx | 28 ++++++++++++++++++++++++++--
 2 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/types/react-native/index.d.ts b/types/react-native/index.d.ts
index f4471fe681..f6b5efe4a5 100644
--- a/types/react-native/index.d.ts
+++ b/types/react-native/index.d.ts
@@ -13,6 +13,7 @@
 //                 Tanguy Krotoff <https://github.com/tkrotoff>
 //                 Alexander T. <https://github.com/a-tarasyuk>
 //                 Martin van Dam <https://github.com/mvdam>
+//                 Kacper Wiszczuk <https://github.com/esemesek>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.8
 
@@ -4810,7 +4811,7 @@ export interface ModalPropsIOS {
      * The `onOrientationChange` callback is called when the orientation changes while the modal is being displayed.
      * The orientation provided is only 'portrait' or 'landscape'. This callback is also called on initial render, regardless of the current orientation.
      */
-    onOrientationChange?: (event?: NativeSyntheticEvent<any>) => void;
+    onOrientationChange?: (event: NativeSyntheticEvent<any>) => void;
 }
 
 export interface ModalPropsAndroid {
@@ -6301,27 +6302,27 @@ export interface ScrollViewProps
      * Fires at most once per frame during scrolling.
      * The frequency of the events can be contolled using the scrollEventThrottle prop.
      */
-    onScroll?: (event?: NativeSyntheticEvent<NativeScrollEvent>) => void;
+    onScroll?: (event: NativeSyntheticEvent<NativeScrollEvent>) => void;
 
     /**
      * Fires if a user initiates a scroll gesture.
      */
-    onScrollBeginDrag?: (event?: NativeSyntheticEvent<NativeScrollEvent>) => void;
+    onScrollBeginDrag?: (event: NativeSyntheticEvent<NativeScrollEvent>) => void;
 
     /**
      * Fires when a user has finished scrolling.
      */
-    onScrollEndDrag?: (event?: NativeSyntheticEvent<NativeScrollEvent>) => void;
+    onScrollEndDrag?: (event: NativeSyntheticEvent<NativeScrollEvent>) => void;
 
     /**
      * Fires when scroll view has finished moving
      */
-    onMomentumScrollEnd?: (event?: NativeSyntheticEvent<NativeScrollEvent>) => void;
+    onMomentumScrollEnd?: (event: NativeSyntheticEvent<NativeScrollEvent>) => void;
 
     /**
      * Fires when scroll view has begun moving
      */
-    onMomentumScrollBegin?: (event?: NativeSyntheticEvent<NativeScrollEvent>) => void;
+    onMomentumScrollBegin?: (event: NativeSyntheticEvent<NativeScrollEvent>) => void;
 
     /**
      * When true the scroll view stops on multiples of the scroll view's size
@@ -8484,7 +8485,7 @@ export namespace Animated {
 
     type Mapping = { [key: string]: Mapping } | AnimatedValue;
     interface EventConfig<T> {
-        listener?: (event?: NativeSyntheticEvent<T>) => void;
+        listener?: (event: NativeSyntheticEvent<T>) => void;
         useNativeDriver?: boolean;
     }
 
diff --git a/types/react-native/test/index.tsx b/types/react-native/test/index.tsx
index c9696e53d0..85d3285329 100644
--- a/types/react-native/test/index.tsx
+++ b/types/react-native/test/index.tsx
@@ -63,6 +63,7 @@ import {
     InputAccessoryView,
     StatusBar,
     NativeSyntheticEvent,
+    NativeScrollEvent,
     GestureResponderEvent,
     TextInputScrollEventData,
     TextInputSelectionChangeEventData,
@@ -388,7 +389,14 @@ export class CapsLockComponent extends React.Component<TextProps> {
     }
 }
 
-class ScrollerListComponentTest extends React.Component<{}, { dataSource: ListViewDataSource }> {
+class ScrollerListComponentTest extends React.Component<
+    {},
+    { dataSource: ListViewDataSource }
+> {
+    eventHandler = (event: NativeSyntheticEvent<NativeScrollEvent>) => {
+        console.log(event);
+    };
+
     render() {
         const scrollViewStyle1 = StyleSheet.create({
             scrollView: {
@@ -406,11 +414,27 @@ class ScrollerListComponentTest extends React.Component<{}, { dataSource: ListVi
                         throw new Error("Expected scroll to be enabled.");
                     }
 
-                    return <ScrollView horizontal={true} nestedScrollEnabled={true} contentOffset={{x: 0, y: 0}} {...props} style={[scrollViewStyle1.scrollView, scrollViewStyle2]} />;
+                    return (
+                        <ScrollView
+                            horizontal={true}
+                            nestedScrollEnabled={true}
+                            contentOffset={{ x: 0, y: 0 }}
+                            {...props}
+                            style={[
+                                scrollViewStyle1.scrollView,
+                                scrollViewStyle2
+                            ]}
+                        />
+                    );
                 }}
                 renderRow={({ type, data }, _, row) => {
                     return <Text>Filler</Text>;
                 }}
+                onScroll={this.eventHandler}
+                onScrollBeginDrag={this.eventHandler}
+                onScrollEndDrag={this.eventHandler}
+                onMomentumScrollBegin={this.eventHandler}
+                onMomentumScrollEnd={this.eventHandler}
             />
         );
     }