add shouldupdate detect

index.js

@@ -58,6 +58,10 @@ export default class PickerAny extends React.Component {
 		this.setState(newState);
 	}
 
+	shouldComponentUpdate(props, state, context){
+		return JSON.stringify([props, state, context]) !== JSON.stringify([this.props, this.state, this.context]);
+	}
+
 	_getStateFromProps(props){
 		//the pickedValue must looks like [wheelone's, wheeltwo's, ...]
 		//this.state.selectedValue may be the result of the first pickerWheel

package.json

 {
   "name": "react-native-picker",
-  "version": "0.2.8",
+  "version": "0.2.9",
   "description": "react-native-picker",
   "main": "index.js",
   "scripts": {
@@ -19,7 +19,7 @@
     "email": "wenliang.web@gmail.com"
   },
   "dependencies": {
-    "react-native-picker-android": "~0.3.4"
+    "react-native-picker-android": "~0.3.5"
   },
   "engines": {
     "node": ">=4"