List.js

import React, { Component } from 'react'
import { View, Text } from 'react-native'
import axios from 'axios'

class List extends Component {

  state = {
    username: this.props.navigation.getParam('name'),
    reposList: []
  }
  constructor(props){
    super(props)
  }
  componentDidMount() {
    axios.get(`https://api.github.com/users/${this.state.username}/repos`)
      .then(response => {
        alert(response)
        this.setState({reposList: response})
      })
      .catch(error => alert(error))
  }

  mountList() {
    return this.state.reposList.map(item, index => {
      return (
        <View>
          <Text>{item.name}</Text>
          <Text>{item.full_name}</Text>
        </View>
      )
    })
  }

  render() {
    return (
      <View>
        <Text>{this.state.reposList}</Text>
      </View>
    )
  }
}

List.navigationOptions = {
  title: 'List'
}

export default List