React_Native_Tutorial/App_plane.js
marcusferl@web.de 4d24511bf8 init
2021-12-29 12:29:29 +01:00

45 lines
1.4 KiB
JavaScript

import React, { Component } from 'react'; // Bei React bzw. Nativ immer importieren!
import { StatusBar } from 'expo-status-bar';
import { Button, StyleSheet, Text, View } from 'react-native';
const data = [
{ text: "Zitat1", author: "Author 1" },
{ text: "Zitat2", author: "Author 2" },
{ text: "Zitat3", author: "Author 3" },
{ text: "Zitat4", author: "Author 4" },
{ text: "Zitat5", author: "Author 5" },
];
export default class App extends Component {
state = { index: 0 }; //initialer Zustand
// Darstellung der Komponente im UI
// Render wird automatisch ausgeführt
// a) Komponente erscheint im Ui (initialer Zustand)
// b) Zustand ändert sich (state) => this.setstate(...)
render() {
let index = this.state.index;
const quote = data[index];
let nextIndex = index + 1;
if (nextIndex === data.length) nextIndex = 0;
return (
//JSX
<View style={styles.container}>
<Text>{quote.text}</Text>
<Text>-- {quote.author}</Text>
<Button title="Nächstes Zitat" onPress={() => this.setState({ index: nextIndex })} />
<StatusBar style="auto" />
</View>
);
}
}
//Aussehen und Layout
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: '#fff',
alignItems: 'center',
justifyContent: 'center',
},
});