update readme file

README.md

@@ -2,9 +2,49 @@
 
 A simple React Native date range picker component
 
+---
+
 ### Installing:
 
 ```
 npm install rnv-date-range-picker
 yarn add rnv-date-range-picker
 ```
+
+![screen shot](https://raw.githubusercontent.com/dilipchandima/rnv-date-range-picker/master/screen.png)
+
+---
+
+## Sample React Native Code
+
+```js
+import React, { useState } from "react";
+import { SafeAreaView, StyleSheet, View, Text } from "react-native";
+import { DateRangePicker } from "rn-date-range-picker";
+
+const App = () => {
+  const [selectedRange, setRange] = useState({});
+  return (
+    <SafeAreaView>
+      <View style={styles.container}>
+        <DateRangePicker
+          onSelectDateRange={(range) => {
+            setRange(range);
+          }}
+          responseFormat="YYYY-MM-DD"
+        />
+        <Text>first date: {selectedRange.firstDate}</Text>
+        <Text>second date: {selectedRange.secondDate}</Text>
+      </View>
+    </SafeAreaView>
+  );
+};
+
+const styles = StyleSheet.create({
+  container: {
+    margin: 50,
+  },
+});
+
+export default App;
+```