text: import React, {Component} from 'react';
  import {ActivityIndicator, View} from "react-native";
  
  export default class App extends Component {
      static navigationOptions = {
          title: 'Activity Indicator',
      };
  
      render() {
          return (
              <View style={{flex: 1, justifyContent: 'center'}}>
                  <ActivityIndicator size="large" color="#0000ff"/>
                  <ActivityIndicator size="small" color="#00ff00"/>
                  <ActivityIndicator size="large" color="#00ff00"/>
                  <ActivityIndicator size="small" color="#0000ff"/>
              </View>
          )
      }
  }