Android Studio 如何操作 CountDownTimer

Question

我正在尝试使用 bool 值暂停 CountDownTimer，当我按下暂停按钮时，tvTimer 停止更新时间，但倒计时计时器不断计数，然后当我按下恢复按钮时，tvTimer 更新倒计时计时器的状态，就像它真正打开的地方一样例如倒数计时器开始说 30 29 28 然后暂停 tvTimer 在 28 停止但实际上倒数计时器仍在工作然后让说倒数计时器现在是 25 但 textview 仍然是 28 对吗？然后我按 resume 显示计时器的 textview 将其更新为 25，其中倒数计时器是我想我只是缺少停止倒数计时器的代码....我真的不知道它是什么 T_T 你们能帮我吗

package org.intercode.lifeatceu;

import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.graphics.Color;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.os.CountDownTimer;
import android.provider.MediaStore;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.Toast;

import org.w3c.dom.Text;

import java.util.HashSet;
import java.util.Random;

public class levelone extends AppCompatActivity {
TextView tv1, tvCred, tvQuestion, tvTimer;
Button btNext, btPause ,btResume;
RadioButton rb1, rb2;
RadioGroup rg;
LinearLayout ll;
CountDownTimer timer;

String questions[] =
        {
                "Dr. Ma Cristina D. Padolina is the President and Chief Academic Officer",
                "Mr. Irineo C. Espino is the Vice President for Academic Affairs",
                "Dr. Teresa R. Perez is the Vice President for Administration and Information Officer",
                "Ms. Corazon M. Tiongco is thr Asst. Treasurer and Procurement Dept. Head",
                "Dr. Rhoda C. Aguilar is the University Registrar",
                "Dr. Olivia M. Limuaca is the Vice President of Malolos Campus",
                "Dr. Ma. Flordeliza L. Anastacio is the Vice President of Makati Campus",
                "Dr. Maria Clara Perlita Erna V. Yabut is the Vice President for Research & Evaluation",
                "Dr. Carlito B. Olaer is the Vice President for Student Affairs",
                "Ms. Bernardita T. Traje is the Asst. Comptroller",
                "Mr. Cesar F. Tan is the Treasurer, Asst. Corporate Secretary & Asst. Compliance Officer",
                "Justice Josue N. Bellosillo is the Dean of School of Law and Jurisprudence at CEU MAKATI",
                "Mr. Marcial L. Anacio is the Program head of Computer Science and Information Tech. Department at CEU MAKATI",
                "Atty. Rita Linda V. Jimeno is the Associate Dean of School of Law and Jurisprudence at CEU MAKATI",
                "Dr. Teresita I. Barcelona is the dean of Nursing at CEU MANILA",
                "Dr. Cecilia C. Uncad is the Dean of Optometry at CEU MANILA",
                "Dr. Jessica L. Flor-Torre is the Dean of Nutrition and Hospitality Management at CEU MANILA",
                "Dean Melito S. Salazar, Jr. is the dean of Accountancy and Management at CEU MANILA",
                "Dr. Charito M. Bermido is the dean of Medical Technology at CEU MANILA",
                "Dr. Teresita G. Carey is the Dean of Science and Technology at CEU MANILA",
                "Dr. Julieta Z. Dungca is the Dean of Educational, Liberal, Arts, Music, Social Wok at CEU MANILA",
                "Dr. Pearly P. Lim is the Dean of Pharmacy at CEU MANILA",
                "Dr. Cecilla D, Santiago is the Dean of Dentistry at CEU MANILA",
                "Dr. Milagros L. Borabo is the Director of Professional and Continuing Educational(PACE)",
                "Dr. Ma. Flordeliza L. Anastacio is the Vice President and Dean of Studies at CEU MALOLOS",
                "Dr. Nilo V. Francisco is the Dean of Management and Technology at CEU MALOLOS",
                "Dr. Elizabeth C. Roces is the Dean of Education, Liberal Arts and Science at CEU MALOLOS",
                "Ms. Veronica F. Balintona is the Asst. Dean of Nutrition and Hospitality management at CEU MANILA",
                "Mrs. Elvira L. Urgel is the Asst. Dean of Nursing at CEU MANILA",
                "Dr. Aileen C. Patron is the Asst. Dean of Medical Technology at CEU MANILA",
                "Dr. Juliana M. Laraya is the Asst. Dean of Educational, Liberal Arts, Music, Social Work at CEU MANILA",
                "Mrs. Emma C. Castro is the Administrative Officer (General Services) at CEU MAKITA",
                "Mrs Julie L. Ibe is the Academic Coordinator of Cash Division at CEU MALOLOS",
                "Mrs. Ma. Armela Pamiloza is the Academic Coordinator Level III Nursing at CEU MALOLOS",
                "Mrs. Rosa M. Quizon is the Academic Coordinator of Level II Nursing at CEU MALOLOS",
                "Mrs. Luningning O. Marcelino is the Academic Coordinator Library Section at CEU MALOLOS",
                "Mrs. Jemelyn O. Garcia is the Academic Coordinator of Community Outreach Section at CEU MALOLOS",
                "Mrs. Shella Marie S. Ignacio is the Head of Tourism Program at CEU MALOLOS",
                "Mrs. Marietta C. Alvarez is the Head of Liberal Arts Program/ Mass Communication Laboratory at CEU MALOLOS",
                "Mrs. Amelia T. Valencia is the head of Marketing Placement at CEU MALOLOS",
                "Mrs. Elvira G. Borlongan is the head of Registrar at CEU MALOLOS",
                "Mrs. Ada Ruth A. Aguasian is the Academic Coordinator of Tourism Management at CEU MAKATI",
                "Dr. Maria Wanda I. Martinez is the Academic Coordinator of Community Nursing at CEU MAKATI",
                "Mr. Rommel Rufuz A. Lopez is the Academic Coordinator of Clinical Dentistry at CEU MAKATI",
                "Dr. Amelita M. Borlongan is the Academic Coordinator of Research at CEU MAKATI",
                "Ms. Annabelle is the Academic Coordinator of Physical Education at CEU MAKATI",
                "Mrs. Maria Victoria S. Coloma is the Academic Coordinator of Clinical Nursing at CEU MAKATI",
                "Dr. Maria Corazon L. Andoy is the Assistant to the Vice President at CEU MAKATI",
                "Mrs. Eleanor C. Reyes is the Coordinator of Science Laboratory at CEU MALOLOS",
                "Dr. Flora L. Camay is the Program Head of Alumni Relation and Education at CEU MALOLOS"
        };
String answer[] =
        {
                "True",//1
                "False",//2
                "False",//3
                "True",//4
                "True",//5
                "False",//6
                "False",//7
                "True",//8
                "True",//9
                "True",//10
                "True",//11
                "True",//12
                "True",//13
                "True",//14
                "True",//15
                "False",//16
                "False",//17
                "True",//18
                "True",//19
                "False",//20
                "False",//21
                "False",//22
                "False",//23
                "True",//24
                "True",//25
                "True",//26
                "True",//27
                "True",//28
                "True",//29
                "True",//30
                "True",//31
                "True",//32
                "False",//33
                "True",//34
                "False",//35
                "False",//36
                "False",//37
                "True",//38
                "True",//39
                "False",//40
                "False",//41
                "True",//42
                "False",//43
                "False",//44
                "True",//45
                "True",//46
                "True",//47
                "True",//48
                "True",//49
                "True",//50

        };
HashSet numbers = new HashSet();


int flag = 0;
Random rnd = new Random();
int flag2 = 0;
int correct = 0;
int wrong = 0;
int coins = 0;
int time = 0;
int credit = 0;

private boolean isPaused = false;
private long timeremaining = 0;

String Executives = "lock";
String Liberators = "lock";
String Travellers = "lock";
String Specialist = "lock";
MediaPlayer mpTimer;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_levelone);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    isPaused = false;

    SharedPreferences loadGame = getSharedPreferences("Game", MODE_PRIVATE);
    credit = loadGame.getInt("savedPlayerCredit", 0);
    time = loadGame.getInt("savedPlayerTime", 0);

    SharedPreferences loadGame2 = getSharedPreferences("Theme", MODE_PRIVATE);
    Executives = loadGame2.getString("Executives", "lock");
    Liberators = loadGame2.getString("Liberators", "lock");
    Specialist = loadGame2.getString("Specialist", "lock");
    Travellers = loadGame2.getString("Travellers", "lock");

    final MediaPlayer mpWrong = MediaPlayer.create(this, R.raw.wrong);
    final MediaPlayer mpCorrect = MediaPlayer.create(this, R.raw.correct);
    final MediaPlayer mpNormal = MediaPlayer.create(this, R.raw.normal);
    mpTimer = MediaPlayer.create(this, R.raw.timer);


    tv1 = (TextView) findViewById(R.id.tv1);
    tvCred = (TextView) findViewById(R.id.tvCred);
    tvQuestion = (TextView) findViewById(R.id.tvQuestion);
    tvTimer = (TextView) findViewById(R.id.tvTimer);

    rb1 = (RadioButton) findViewById(R.id.rb1);
    rb2 = (RadioButton) findViewById(R.id.rb2);
    rg = (RadioGroup) findViewById(R.id.rg);

    btNext = (Button) findViewById(R.id.btNext);
    btPause = (Button) findViewById(R.id.btPause);
    btResume = (Button) findViewById(R.id.btResume);
    btNext.setBackgroundResource(R.drawable.next);

    ll = (LinearLayout) findViewById(R.id.ll);

    if (Executives.equals("active")) {
        time = time + 5000;
    } else if (Liberators.equals("active")) {
        coins = coins + 20;
    } else if (Travellers.equals("active")) {
        time = time + 5000;
    } else if (Specialist.equals("active")) {
        coins = coins + 20;
    } else {
        Toast.makeText(this, "Go!", Toast.LENGTH_SHORT).show();
    }

    flag2 = rnd.nextInt(50);
    numbers.add(flag2);
    tvQuestion.setText(questions[flag2]);
    tvCred.setText(String.valueOf(credit));
    mpTimer.start();


    timer = new CountDownTimer(time, 1000) {
        public void onTick(long millisUntilFinished) {
            if(isPaused)
            {
                timer.cancel();
            }
            else
            {
                tvTimer.setText("" + millisUntilFinished / 1000);
                timeremaining=millisUntilFinished;
            }
        }

        @Override
        public void onFinish() {

            Intent inResult = new Intent(getApplicationContext(), Results.class);
            SharedPreferences saveGame = getSharedPreferences("Game", MODE_PRIVATE);
            SharedPreferences.Editor editor = saveGame.edit();
            editor.putInt("savedPlayerCredit", credit);
            editor.putInt("savedPlayerCoins", coins);
            editor.putInt("savedPlayerCorrect", correct);
            editor.putInt("savedPlayerWrong", wrong);
            editor.apply();
            startActivity(inResult);
            mpTimer.stop();
        }
    }.start();

            btNext.setOnClickListener(new View.OnClickListener() {
                                  @Override
                                  public void onClick(View v) {
                                      btNext.setBackgroundResource(R.drawable.nextonclick);
                                      if (rg.getCheckedRadioButtonId() == -1) {
                                          Toast.makeText(getApplicationContext(), "Choose an Answer", Toast.LENGTH_LONG).show();
                                      } else {
                                          RadioButton uans = (RadioButton) findViewById(rg.getCheckedRadioButtonId());
                                          String ansText = uans.getText().toString();
                                          if (ansText.equalsIgnoreCase(answer[flag2])) {
                                              while (numbers.contains(flag2)) {
                                                  flag2 = rnd.nextInt(50);
                                              }
                                              correct++;
                                              coins++;
                                              mpCorrect.start();
                                              Toast.makeText(getApplicationContext(), "Correct!", Toast.LENGTH_SHORT).show();
                                          } else {
                                              wrong++;
                                              mpWrong.start();
                                              Toast.makeText(getApplicationContext(), "Wrong!", Toast.LENGTH_SHORT).show();
                                          }
                                          flag++;
                                          flag2 = rnd.nextInt(50);

                                          if (flag < questions.length) {
                                              tvQuestion.setText(questions[flag2]);
                                              rb1.setChecked(false);
                                              rb2.setChecked(false);
                                              rg.clearCheck();
                                              btNext.setBackgroundResource(R.drawable.next);
                                          } else {
                                              Intent inResult = new Intent(getApplicationContext(), Results.class);
                                              SharedPreferences saveGame = getSharedPreferences("Game", MODE_PRIVATE);
                                              SharedPreferences.Editor editor = saveGame.edit();
                                              editor.putInt("savedPlayerCredit", credit);
                                              editor.putInt("savedPlayerCoins", coins + 100);
                                              editor.putInt("savedPlayerCorrect", correct);
                                              editor.putInt("savedPlayerWrong", wrong);
                                              editor.apply();
                                              timer.cancel();
                                              startActivity(inResult);
                                              mpTimer.stop();
                                          }
                                      }
                                      mpNormal.start();
                                  }
                              });
    btPause.setOnClickListener(new View.OnClickListener()
    {
        @Override
        public void onClick(View v) {
            isPaused = true;
            mpTimer.stop();
        }
    });
    btResume.setOnClickListener(new View.OnClickListener()
    {
        @Override
        public void onClick(View v){
            isPaused = false;
            mpTimer.start();
        }
    });
}

@Override
public void onBackPressed() {
    AlertDialog.Builder builder = new AlertDialog.Builder(this);

    builder.setTitle("Quit");
    builder.setMessage("Are you sure you want to Quit?");

    builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {

        public void onClick(DialogInterface dialog, int which) {
            timer.onFinish();
        }
    });
    builder.setNegativeButton("No", new DialogInterface.OnClickListener() {

        @Override
        public void onClick(DialogInterface dialog, int which) {

            dialog.dismiss();
        }
    });

    AlertDialog alert = builder.create();
    alert.show();
}

@Override
protected void onStop() {
    super.onStop();
    timer.cancel();
    mpTimer.stop();
}

@Override
protected void onUserLeaveHint() {
    super.onUserLeaveHint();

}
  }

Answer 1

这就是我要做的。我会在 onTick 处理程序中添加一些内容，以保存类中计时器的进度(类似于 timeLeft = millisUntilFinished/1000;)

当你想暂停计时器时，执行timer.cancel()。当你想继续运行计时器时，创建一个新的计时器，保留剩余的毫秒数。

这样，您就无需担心计时器在应该暂停时是否仍在运行，以及将额外的值传递给 CountDownTimer。

编辑:

您可以创建一个私有(private)方法来在需要时创建一个新的 CountDownTimer:

private CountDownTimer createTimer(int time){
return new CountDownTimer(time*1000, 1000) {
    @Override
        public void onTick(long millisUntilFinished) {
            tvTimer.setText("" + millisUntilFinished / 1000);
            timeLeft = millisUntilFinished / 1000;
    }

    @Override
    public void onFinish() {
        //Do what you want, cancel the timer...
    }
}.start();

添加一个全局变量

private CountDownTimer timer;

当你需要创建一个 CountDownTimer 时:

timer = createCountDownTimer(yourTime);

如果你想暂停，请执行 timer.cancel();