set the image size in react native code example

Example 1: resize image react native

image : {
		width      : null,
		resizeMode : 'contain',
		height     : 220
	}

Example 2: react native asign width to image

import { Dimensions } from "react-native";
const win = Dimensions.get('window');

<Image
  style={{
    width: win.width/2,
    height: win.width/2,
    resizeMode: "contain",
    alignSelf: "center",
    borderWidth: 1,
    borderRadius: 20,
  }}
  source={{uri:'https://facebook.github.io/react/img/logo_og.png'}}
  resizeMode="stretch"
/>