ErEduGilMor/screens/main/Calendar.js

import React, { Component } from 'react';
import {
  StyleSheet,
  Text,
  View
} from 'react-native';
import CalendarPicker from 'react-native-calendar-picker';
import {Calendar, CalendarList} from 'react-native-calendars';


export default class Calendario extends Component {
  constructor(props) {
    super(props);
    this.state = {
      selectedStartDate: null,
    };
    this.onDayPress = this.onDayPress.bind(this);
    
  }

  onDayPress(date) {
    this.setState({
      selectedStartDate: date,
    });

    this.props.navigation.navigate('StateTime', {Appointment_Date: date});
  }
  
  render() {
    const { selectedStartDate } = this.state;
    const today = new Date();
    const appointment = selectedStartDate ? selectedStartDate.toString() : '';
    return (
      <View style={styles.container}>
        <Calendar
        onVisibleMonthsChange={(months) => {console.log('now these months are visible', months);}}
          minDate={today}
          onDayPress={this.onDayPress}
        />
      </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: '#FFFFFF',
    marginTop: 100,
  },
});