안드로이드 카운트다운 앱 만들기

안드로이드 카운트다운 앱을 만들어 보겠습니다. 10에서 숫자가 1씩 감소되는 카운트 앱입니다.

먼저 리소스에서 activity_mail.xml에서 텍스트뷰를 한개만 추가해주세요 

   <TextView
        android:id="@+id/count_txt"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

 

그리고 다음과 같이 자바 MainActivity를 코딩하면 됩니다.

 

package com.jw.countdown;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.os.CountDownTimer;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    private static final int TOTAL = 11 * 1000;
    private static final int COUNT_DOWN_INTERVAL = 1000;

    private int count = 10;
    private TextView countTxt;
    private CountDownTimer countDownTimer;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        countTxt = findViewById(R.id.count_txt);
        countDownTimer();
        countDownTimer.start();
    }

    public void countDownTimer(){
        countDownTimer = new CountDownTimer(TOTAL, COUNT_DOWN_INTERVAL) {
            @Override
            public void onTick(long millisUntilFinished) {
                countTxt.setText(String.valueOf(count));
                count--;


            }

            @Override
            public void onFinish() {

                countTxt.setText("카운트 종료");

            }
        };
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        try{
            countDownTimer.cancel();
        }catch (Exception e){

        }

        countDownTimer = null;
    }
}

 

 

https://youtu.be/aWR1ip1g0Ng