text: 
  //dependecies
  import React, { Component } from 'react';
  import { Text, View, Image,  Keyboard, TouchableWithoutFeedback, TouchableOpacity, Dimensions, PixelRatio, KeyboardAvoidingView } from 'react-native';
  import Constants from 'expo-constants';
  
  //components
  import Screen from './../components/Screen';
  import Button from './../components/Button';
  import Line from './../components/Line';
  
  //styles
  import { _bgGrisClaroApp, _bgVerdeApp, _bgFacebook  } from "../styles/globalStyles";
  
  //forms
  import SingInForm from './../forms/SingInForm';
  import { StyleSheet } from 'react-native';
  import { Platform } from 'react-native';
  
  
  class SignInScreen extends Component {
      render() {
  
          const {navigation} = this.props
     
          return (
              <KeyboardAvoidingView style={styles.inputZone} behavior='padding' enabled keyboardVerticalOffset={-150}>
              <Screen scrollable={false} >                
                      
                      <View style={styles.container}>
  
                          <TouchableWithoutFeedback onPress={Keyboard.dismiss} accessible={false}>
                              <View style={styles.header}>
                                  <Image style={styles.logo} source={require('../assets/logo.png')}></Image>
                                  {/* <Text style={styles.logotipo}>Pay</Text> */}
                              </View>
                          </TouchableWithoutFeedback>
  
                          <View style={styles.authOptions}>
  
                              <TouchableWithoutFeedback onPress={Keyboard.dismiss} accessible={false}>
                                  <Text style={styles.titleH1}>Iniciar sesión</Text>
                              </TouchableWithoutFeedback>
                              
                              <SingInForm/>
                              
                              <Button 
                                  textButton= 'Ingresar con facebook' 
                                  _bgButton={_bgFacebook}
                                  onPressFn={()=>navigation.navigate('HOME')}                                
                              />
                              <Line color={'#219653'} margin={2}></Line>
                              <Text style={styles.message}>¿Todavía no tenes cuenta?</Text>
                              <TouchableOpacity 
                                  style={styles.option}
                                  onPress={()=>navigation.navigate('REGISTER')}
                              >
                                  <Text style={styles.buttonText}>Crear cuenta</Text>
                              </TouchableOpacity>
  
                          </View>
  
                      </View>
                          
                          
                          
                  
              </Screen>
              </KeyboardAvoidingView>
              
              
          );
      }
  }
  
  const deviceWidth = Dimensions.get('window').width
  console.log(`Ancho en dp: ${deviceWidth}`);
  const deviceHeight = Dimensions.get('window').height
  const fnValue = x => PixelRatio.roundToNearestPixel((deviceWidth*x)/100);
  // console.log('Dimensions.screen');
  // console.log(Dimensions.get('window'));
  // console.log('Dimensions.screen');
  // console.log(Dimensions.get('window'));
  console.log(` deviceName: ${Constants.deviceName}`);
  deviceWidthSelect = 414;
  const alfa = deviceWidth / deviceWidthSelect;
  
  export const isIphoneX = () => {
      const dimen = Dimensions.get('window')
      return (
        Platform.OS === 'ios' && !Platform.isPad && !Platform.isTVOS && 
        (dimen.height === 812 || dimen.width === 812 || (dimen.height === 896 || dimen.width === 896))
      )
  }
  
  const footerSafe = isIphoneX() ? 40:10
  
  const styles = StyleSheet.create({
      container:{flex:1,justifyContent:'space-between',paddingHorizontal:30},
      logo:{marginBottom:15, height:'40%',aspectRatio:1},
      logotipo:{fontSize: 0.035*deviceHeight, fontWeight:'600', marginBottom:5,color:'#219653'},
      titleH1:{fontSize: 27, fontWeight:'500', marginBottom:30,color:'#333333'},
      message:{fontSize: 20, fontWeight:'400', marginBottom:10,marginTop:10,color:'#333333'},
      option:{height:50, justifyContent:'center', alignItems:'center'},
      buttonText:{fontSize: 20, fontWeight:'400',color:'#333333',textDecorationLine: 'underline'},
      authOptions:{alignItems:'center',width:'100%',paddingBottom:footerSafe, justifyContent:'flex-end'},
      header:{flex:1, paddingTop:Constants.statusBarHeight, justifyContent:'center', alignItems:'center'},
      inputZone:{width:'100%',flex:1}
  })
  
  export default SignInScreen;