react native dynamic view size

JavaScript
const messages = [
              'hello',
              'this is supposed to be a bit of a long line.',
              'bye'
              ];
return (
  <View style={{
            position: 'absolute',
            top: 0,
            left: 0,
            width: 150,
            alignItems: 'flex-end',
            justifyContent: 'flex-start',
            backgroundColor: '#fff',
            }}>

{messages.map( (message, index) => (
  <View key={index} style={{
                  flexDirection: 'row',
                  marginTop: 10
                }}>
    <View style={{
                  flex: -1,
                  marginLeft: 5,
                  marginRight: 5,
                  backgroundColor: '#CCC',
                  borderRadius: 10,
                  padding: 5,
                }}>
      <Text style={{
                    fontSize: 12,
                    }}>
        {message}
      </Text>
    </View>
    <Image source={require('some_path')} style={{width:30,height:30}} />
   </View> 
  ))} 
 </View>
)
Source

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