hello

src/FlatListItem.js

@@ -1,46 +1,51 @@
-import React from 'react'
-import { 
-  View,
-} from 'react-native'
-
+import React from "react";
+import { View } from "react-native";
+import PropTypes from "prop-types";
 
 export default class FlatListItem extends React.PureComponent {
   static propTypes = {
-    viewComponent: React.PropTypes.element.isRequired
+    viewComponent: PropTypes.element.isRequired
   };
 
   constructor(props) {
     super(props);
     this.state = {
-      visibility: true,
-    }
+      visibility: true
+    };
   }
 
   onLayout(evt) {
     this.viewProperties = {
       width: 0,
-      height: 0,
-    }
+      height: 0
+    };
     this.viewProperties.width = evt.nativeEvent.layout.width;
     this.viewProperties.height = evt.nativeEvent.layout.height;
   }
 
   setVisibility(visibility) {
     if (this.state.visibility != visibility) {
-      if (visibility == true) this.setState({ visibility: true })
-      else this.setState({ visibility: false })
+      if (visibility == true) this.setState({ visibility: true });
+      else this.setState({ visibility: false });
     }
   }
 
   render() {
     if (this.state.visibility === false) {
-      return ( <View style={{ width: this.viewProperties.width, height: this.viewProperties.height }} /> )
+      return (
+        <View
+          style={{
+            width: this.viewProperties.width,
+            height: this.viewProperties.height
+          }}
+        />
+      );
     }
 
     return (
       <View onLayout={this.onLayout.bind(this)}>
         {this.props.viewComponent}
       </View>
-    )
+    );
   }
 }

src/OptimizedFlatList.js

@@ -1,67 +1,69 @@
-import React from 'react'
-import { 
-  FlatList,
-} from 'react-native'
+import React from "react";
+import { FlatList } from "react-native";
 
-import FlatListItem from './FlatListItem'
+import FlatListItem from "./FlatListItem";
 
 export default class OptimizedFlatList extends React.PureComponent {
-
   constructor(props) {
     super(props);
-    this.state = {}
-    this.rowRefs =[]
+    this.state = {};
+    this.rowRefs = [];
+  }
+
+  /**
+   * Scroll to a specific content pixel offset in the list.
+   */
+  scrollToOffset(params: { animated?: ?boolean, offset: number }) {
+    this._listRef.scrollToOffset(params);
   }
 
-  _addRowRefs(ref, data){
+  _addRowRefs(ref, data) {
     this.rowRefs[data.index] = {
       ref: ref,
       item: data.item,
-      index: data.index,
-    }
+      index: data.index
+    };
   }
-  
-  _updateItem(index, visibility){
-        if (!this.rowRefs[index].ref) {
+
+  _updateItem(index, visibility) {
+    if (!this.rowRefs[index].ref) {
       return false;
     }
-    this.rowRefs[index].ref.setVisibility(visibility)
-    return visibility
+    this.rowRefs[index].ref.setVisibility(visibility);
+    return visibility;
   }
 
-  _renderItem(data){
-    const view = this.props.renderItem(data)
+  _renderItem(data) {
+    const view = this.props.renderItem(data);
     return (
       <FlatListItem
-        ref={ myItem => this._addRowRefs(myItem, data)}
+        ref={myItem => this._addRowRefs(myItem, data)}
         viewComponent={view}
         data={data}
       />
-    )
+    );
   }
 
-  _onViewableItemsChanged (info: {
-      changed: Array<{
-        key: string,
-        isViewable: boolean,
-        item: any,
-        index: ?number,
-        section?: any,
-      }>
-    }
-  ) {
-    info.changed.map(item => 
-      this._updateItem(item.index, item.isViewable)
-    )
+  _onViewableItemsChanged(info: {
+    changed: Array<{
+      key: string,
+      isViewable: boolean,
+      item: any,
+      index: ?number,
+      section?: any
+    }>
+  }) {
+    info.changed.map(item => this._updateItem(item.index, item.isViewable));
   }
 
   render() {
     return (
       <FlatList
         {...this.props}
-        renderItem={ data => this._renderItem(data) }
+        renderItem={data => this._renderItem(data)}
         onViewableItemsChanged={this._onViewableItemsChanged.bind(this)}
+        ref={ref => (this._listRef = ref)}
       />
-    )
+    );
   }
 }