การทำ Circle Timer ด้วย React Native

import React, { useState, useEffect } from 'react';
import { View, StyleSheet, Text, TouchableOpacity } from 'react-native';

const Timer = () => {
  const [time, setTime] = useState(25 * 60); // 25 minutes in seconds

  useEffect(() => {
    let interval = null;

    if (time > 0) {
      interval = setInterval(() => {
        setTime((prevTime) => prevTime - 1);
      }, 1000);
    }

    return () => {
      clearInterval(interval);
    };
  }, []);

  const formatTime = (seconds) => {
    const minutes = Math.floor(seconds / 60);
    const remainingSeconds = seconds % 60;

    return `${minutes.toString().padStart(2, '0')}:${remainingSeconds.toString().padStart(2, '0')}`;
  };

return (
    <View style={styles.container}>
       <View style={styles.circle}>
          <Text style={styles.timer}>{formatTime(time)}</Text>
       </View>
    </View>
  );
};

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
  },
  circle: {
    width: 200,
    height: 200,
    borderRadius: 100,
    borderWidth: 10,
    borderColor: 'red',
    justifyContent: 'center',
    alignItems: 'center',
  },
  timer: {
    fontSize: 60,
    fontWeight: 'bold',
    textAlign: 'center',
  },
});
export default Timer;

<View style={styles.buttonContainer}>
      <TouchableOpacity style={styles.button} onPress={handleButtonPress} disabled={true}>
        <Text style={styles.startbuttonText}>Start</Text>
      </TouchableOpacity>
      <TouchableOpacity style={styles.button} onPress={handleButtonPress} disabled={true}>
        <Text style={styles.stopbuttonText}>Stop</Text>
      </TouchableOpacity>
      <TouchableOpacity style={styles.button} onPress={handleButtonPress} disabled={true}>
        <Text style={styles.resetbuttonText}>Reset</Text>
      </TouchableOpacity>
</View>

buttonContainer: {
    marginTop: 20,
  },
  button: {
    backgroundColor: 'black',
    paddingVertical: 10,
    paddingHorizontal: 20,
    borderRadius: 5,
    marginBottom: 10,
  },
  buttonText: {
    fontSize: 16,
    textAlign: 'center',
    color: 'white',
  },
  stopbuttonText: {
    fontSize: 16,
    textAlign: 'center',
    color: 'white',
    backgroundColor: 'red',
  },
  startbuttonText: {
    fontSize: 16,
    textAlign: 'center',
    color: 'white',
    backgroundColor: 'green',
  },
  resetbuttonText: {
    fontSize: 16,
    textAlign: 'center',
    color: 'black',
    backgroundColor: 'yellow',
  },

import React, { useState, useEffect } from 'react';
import { View, StyleSheet, Text, TouchableOpacity } from 'react-native';

const Timer = () => {
  const [time, setTime] = useState(25 * 60); // 25 minutes in seconds

  useEffect(() => {
    let interval = null;

    if (time > 0) {
      interval = setInterval(() => {
        setTime((prevTime) => prevTime - 1);
      }, 1000);
    }

    return () => {
      clearInterval(interval);
    };
  }, []);

  const formatTime = (seconds) => {
    const minutes = Math.floor(seconds / 60);
    const remainingSeconds = seconds % 60;

    return `${minutes.toString().padStart(2, '0')}:${remainingSeconds.toString().padStart(2, '0')}`;
  };

  return (
    <View style={styles.buttonContainer}> 
      <TouchableOpacity style={styles.button} onPress={handleButtonPress} disabled={true}> 
        <Text style={styles.startbuttonText}>Start</Text> 
      </TouchableOpacity> 
      <TouchableOpacity style={styles.button} onPress={handleButtonPress} disabled={true}> 
        <Text style={styles.stopbuttonText}>Stop</Text> 
      </TouchableOpacity> <TouchableOpacity style={styles.button} onPress={handleButtonPress} disabled={true}> 
        <Text style={styles.resetbuttonText}>Reset</Text> 
      </TouchableOpacity> </View>
  );
};

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
  },
  circle: {
    width: 200,
    height: 200,
    borderRadius: 100,
    borderWidth: 10,
    borderColor: 'red',
    justifyContent: 'center',
    alignItems: 'center',
  },
  timerText: {
    fontSize: 60,
    fontWeight: 'bold',
    textAlign: 'center',
  },
  buttonContainer: {
    marginTop: 20,
  },
  button: {
    backgroundColor: 'black',
    paddingVertical: 10,
    paddingHorizontal: 20,
    borderRadius: 5,
    marginBottom: 10,
  },
  buttonText: {
    fontSize: 16,
    textAlign: 'center',
    color: 'white',
  },
  stopbuttonText: {
    fontSize: 16,
    textAlign: 'center',
    color: 'white',
    backgroundColor: 'red',
  },
  startbuttonText: {
    fontSize: 16,
    textAlign: 'center',
    color: 'white',
    backgroundColor: 'green',
  },
  resetbuttonText: {
    fontSize: 16,
    textAlign: 'center',
    color: 'black',
    backgroundColor: 'yellow',
  },
});

export default Timer;