diff --git a/index.js b/index.js
index cbef288..863242a 100644
--- a/index.js
+++ b/index.js
@@ -1,6 +1,6 @@
 'use strict';
 
-import React, {Component, PropTypes} from 'react';
+import React, { Component } from 'react';
 import {
 	StyleSheet,
 	View, 
@@ -8,8 +8,10 @@ import {
 	Image,
 	Dimensions,
 	PixelRatio,
-	PanResponder
+	PanResponder,
+	ViewPropTypes,
 } from 'react-native';
+import PropTypes from "prop-types";
 
 class PickerAndroidItem extends Component{
 
@@ -34,7 +36,7 @@ export default class PickerAndroid extends Component{
 
 	static propTypes = {
 		//picker's style
-		pickerStyle: View.propTypes.style,
+		pickerStyle: ViewPropTypes.style,
 		//picker item's style
 		itemStyle: Text.propTypes.style,
 		//picked value changed then call this function
@@ -205,7 +207,9 @@ export default class PickerAndroid extends Component{
 		//but PickerIOS only passed value, so we set label to be the second argument
 		//add by zooble @2015-12-10
 		var curItem = this.state.items[this.index];
-		this.state.onValueChange && this.state.onValueChange(curItem.value, curItem.label);
+		if (curItem && this.state.onValueChange) {
+			this.state.onValueChange(curItem.value, curItem.label);
+		}
 	}
 
 	render(){
@@ -267,7 +271,8 @@ let styles = StyleSheet.create({
 	},
 	up: {
 		height: 90,
-		overflow: 'hidden'
+		overflow: 'hidden',
+		backgroundColor: 'transparent',
 	},
 	upView: {
 		justifyContent: 'flex-start',
@@ -289,7 +294,8 @@ let styles = StyleSheet.create({
 		overflow: 'hidden',
 		borderColor: '#aaa',
 		borderTopWidth: 1/ratio,
-		borderBottomWidth: 1/ratio
+		borderBottomWidth: 1/ratio,
+		backgroundColor: 'transparent',
 	},
 	middleView: {
 		height: 40,
@@ -307,12 +313,14 @@ let styles = StyleSheet.create({
 	},
 	down: {
 		height: 90,
-		overflow: 'hidden'
+		overflow: 'hidden',
+		backgroundColor: 'transparent',
 	},
 	downView: {
 		overflow: 'hidden',
 		justifyContent: 'flex-start',
-		alignItems: 'center'
+		alignItems: 'center',
+		backgroundColor: 'transparent',
 	},
 	downText: {
 		paddingTop: 0,
diff --git a/package.json b/package.json
index b11f4fd..a9bd017 100644
--- a/package.json
+++ b/package.json
@@ -26,5 +26,8 @@
   "bugs": {
     "url": "https://github.com/beefe/react-native-picker-android/issues"
   },
-  "homepage": "https://github.com/beefe/react-native-picker-android#readme"
+  "homepage": "https://github.com/beefe/react-native-picker-android#readme",
+  "dependencies": {
+    "prop-types": "^15.6.0"
+  }
 }