vertical - react-native flexbox cheat sheet




100% width in React Native Flexbox (6)

Noted: Try to fully understanding about flex concept.

       <View style={{
          flex: 2,
          justifyContent: 'center',
          alignItems: 'center'
        }}>
          <View style ={{
              flex: 1,
              alignItems: 'center, 
              height: 50, 
              borderWidth: 1, 
              borderColor: '#000' 
          }}>
               <Text>Welcome to React Nativ</Text>
           </View>
           <View style={{
              flex: 1,
              alignItems: 'center,
              borderWidth: 1, 
              borderColor: 'red ', 
              height: 50
            }}
            >
              <Text> line 1 </Text>
            </View>
          <View style={{
            flex: 1,
            alignItems: 'center, 
            height: 50, 
            borderWidth: 1,                     
            borderColor: '#000'
          }}>
             <Text>
              Press Cmd+R to reload,{'\n'}
              Cmd+D or shake for dev menu
             </Text>
           </View>
       </View>

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?

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:

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,
  },

First add Dimension component:

import { AppRegistry, Text, View,Dimensions } from 'react-native';

Second define Variables:

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

Third put it in your stylesheet:

textOutputView: {
    flexDirection:'row',
    paddingTop:20,
    borderWidth:1,
    borderColor:'red',
    height:height*0.25,
    backgroundColor:'darkgrey',
    justifyContent:'flex-end'
}

Actually in this example I wanted to make responsive view and wanted to view only 0.25 of the screen view so I multiplied it with 0.25, if you wanted 100% of the screen don't multiply it with any thing like this:

textOutputView: {
    flexDirection:'row',
    paddingTop:20,
    borderWidth:1,
    borderColor:'red',
    height:height,
    backgroundColor:'darkgrey',
    justifyContent:'flex-end'
}


Use javascript to get the width and height and add them in View's style. To get full width and height, use Dimensions.get('window').width https://facebook.github.io/react-native/docs/dimensions.html

getSize() {
    return {
        width: Dimensions.get('window').width, 
        height: Dimensions.get('window').height
    }
}

and then,

<View style={[styles.overlay, this.getSize()]}>

just remove the alignItems: 'center' in the container styles and add textAlign: "center" to the line1 style like given below.

It will work well

container: {
  flex: 1,
  justifyContent: 'center',
  backgroundColor: '#F5FCFF',
  borderWidth: 1,
}

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

Editted:

In order to flex only the center text, a different approach can be taken - Unflex the other views.

  • Let flexDirection remain at 'column'
  • remove the alignItems : 'center' from container
  • add alignSelf:'center' to the textviews that you don't want to flex

You can wrap the Text component in a View component and give the View a flex of 1.

The flex will give :

100% width if the flexDirection:'row' in styles.container

100% height if the flexDirection:'column' in styles.container