100% width in React Native Flexbox

I have already read several flexbox tutorial, but I still cannot make this simple task to work.

How can I make the red box to 100% width?

enter image description here

Code:

  <View style={styles.container}>
    <Text style={styles.welcome}>
      Welcome to React Natives
    </Text>
    <Text style={styles.line1}>
      line1
    </Text>
    <Text style={styles.instructions}>
      Press Cmd+R to reload,{'\n'}
      Cmd+D or shake for dev menu
    </Text>
  </View>

style:

container: {
  flex: 1,
  justifyContent: 'center',
  alignItems: 'center',
  backgroundColor: '#F5FCFF',
  borderWidth: 1,
  flexDirection: 'column',
},
welcome: {
  fontSize: 20,
  textAlign: 'center',
  margin: 10,
  borderWidth: 1,
},
line1: {
    backgroundColor: '#FDD7E4',
},
instructions: {
  textAlign: 'center',
  color: '#333333',
  marginBottom: 5,
  borderWidth: 1,
},

Thank you!

Update 1: Suggestion by Nishanth Shankar, adding flex:1 for the wrapper, flexDirection: 'row'

Output:

enter image description here

Code:

  <View style={styles.container}>
    <View style={{flex:1}}>
      <Text style={styles.welcome}>
        Welcome to React Natives
      </Text>
    </View>
    <View style={{flex:1}}>
      <Text style={styles.line1}>
        line1
      </Text>
    </View>
    <View style={{flex:1}}>
      <Text style={styles.instructions}>
        Press Cmd+R to reload,{'\n'}
        Cmd+D or shake for dev menu
      </Text>
    </View>
  </View>

  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    backgroundColor: '#F5FCFF',
    borderWidth: 1,
    flexDirection: 'row',
    flexWrap: 'wrap',
  },
  welcome: {
    fontSize: 20,
    textAlign: 'center',
    margin: 10,
    borderWidth: 1,
  },
  line1: {
      backgroundColor: '#FDD7E4',
  },
  instructions: {
    textAlign: 'center',
    color: '#333333',
    marginBottom: 5,
    borderWidth: 1,
  },

Simply add alignSelf: "stretch" to your item's stylesheet.

line1: {
    backgroundColor: '#FDD7E4',
    alignSelf: 'stretch',
    textAlign: 'center',
},

You should use Dimensions

First, define Dimensions.

import { Dimensions } from "react-native";

var width = Dimensions.get('window').width; //full width
var height = Dimensions.get('window').height; //full height

then, change line1 style like below:

line1: {
    backgroundColor: '#FDD7E4',
    width: width,
},