App.js

import { useState } from "react";
import { Button, StyleSheet, Text, TextInput, View } from "react-native";

export default function App() {
  const [enteredGoalText, setEnteredGoalText] = useState("");
  const [courseGoals, setCourseGoals] = useState([]);

  function goalInputHandler(enteredText) {
    setEnteredGoalText(enteredText);
  }

  function addGoalHandler() {
    setCourseGoals((currentCourseGoals) => [
      ...currentCourseGoals,
      enteredGoalText,
    ]);
  }

  return (
    <View style={styles.rootContainer}>
      <View style={styles.inputContainer}>
        <TextInput
          style={styles.textInput}
          placeholder="Enter Goal Here..."
          onChangeText={goalInputHandler}
        />
        <Button title="Add Goal" onPress={addGoalHandler} />
      </View>
      <View style={styles.goalsContainer}>
        {courseGoals.map((goal) => (
          <Text key={goal}>{goal}</Text>
        ))}
      </View>
    </View>
  );
}

const styles = StyleSheet.create({
  rootContainer: {
    flex: 1,
    paddingTop: 50,
    paddingHorizontal: 16,
  },
  inputContainer: {
    flex: 1,
    flexDirection: "row",
    justifyContent: "space-between",
    alignItems: "center",
    marginBottom: 20,
    borderBottomWidth: 1,
    borderBottomColor: "#cccccc",
  },
  textInput: {
    // height: 40,
    marginRight: 20,
    paddingLeft: 10,
    paddingTop: 6,
    paddingBottom: 6,
    width: "70%",
    borderColor: "#cccccc",
    borderWidth: 1,
  },
  goalsContainer: {
    flex: 4,
  },
});