java - android studio 倒数计时器的问题

Question

我对 Java 很陌生，我正在尝试创建一个从 5:00 分钟到 0 调用倒计时器的 Activity 。但是，我遇到了一些问题。我尝试了那里的每个示例代码。你们能帮我吗？

import androidx.appcompat.app.AppCompatActivity;    
import java.util.Locale;  

public class Main4Activity extends AppCompatActivity {      

    new CountDownTimer(30000, 1000) {

        public void onTick(long millisUntilFinished) {
            mTextField.setText("seconds remaining: " + millisUntilFinished / 1000);
        }

        public void onFinish() {
            mTextField.setText("done!");
        }
    }.start();

Answer 1

已修复!

int minute;
long min;
TextView tv_timer;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main4);

    tv_timer=findViewById(R.id.contador);
    minute=Integer.parseInt("5");
    min= minute*60*1000;
    counter(min);



}
private void counter(long min) {
    CountDownTimer timer = new CountDownTimer(min, 1000) {
        public void onTick(long millisUntilFinished) {
            int seconds = (int) (millisUntilFinished / 1000) % 60;
            int minutes = (int) ((millisUntilFinished / (1000 * 60)) % 60);

            tv_timer.setText(String.format("%d:%d", minutes, seconds));
        }
        public void onFinish() {
            Toast.makeText(getApplicationContext(), "Your time has been completed",
                    Toast.LENGTH_LONG).show();
        }
    };
    timer.start();
}

}