如何在Android中制作倒数计时器?

Sab*_*med 157 android timer countdown

我有两个XML格式的EditTexts.在一个EditText中,用户可以将数字设置为分钟,而将另一个EditText设置为秒数.单击完成按钮后,秒EditText应开始倒计时并每秒更新其文本.

另外,如何保持更新直到达到零分钟和零秒?

Sha*_*wal 367

new CountDownTimer(30000, 1000) {

    public void onTick(long millisUntilFinished) {
        mTextField.setText("seconds remaining: " + millisUntilFinished / 1000);
       //here you can have your logic to set text to edittext
    }

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

}.start();
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请参阅此链接.

  • 这是一个很好的答案,但任何人都可以告诉我如何进行自定义倒计时时间,而不是只输入30秒?我尝试从EditText中获取值,但它似乎根本不起作用. (3认同)

sha*_*han 67

如果您使用以下代码(如接受的答案中所述),

new CountDownTimer(30000, 1000) {

    public void onTick(long millisUntilFinished) {
        mTextField.setText("seconds remaining: " + millisUntilFinished / 1000);
       //here you can have your logic to set text to edittext
    }

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

}.start();
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如果您不仔细清理引用,它将导致您使用此代码的活动实例的内存泄漏.

使用以下代码

//Declare timer
CountDownTimer cTimer = null;

//start timer function
void startTimer() {
    cTimer = new CountDownTimer(30000, 1000) {
        public void onTick(long millisUntilFinished) {
        }
        public void onFinish() {
        }
    };
    cTimer.start();
}


//cancel timer
void cancelTimer() {
    if(cTimer!=null)
        cTimer.cancel();
}
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只要调用拥有的Activity/Fragment中的onDestroy()/ onDestroyView(),就需要调用cTtimer.cancel().

  • 是的!10/10。这应该是正确的答案。或者,即使您按“BACK”,countDownThread 仍然可以正常工作。你可以放置一个 Log.i,如果你不放置“.cancel()”,你会看到它每 1 秒抛出一次信息。 (2认同)

San*_*iya 48

在此输入图像描述

MainActivity.java

package com.zeustechnocrats.countdown;

import android.os.Bundle;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;

import java.text.SimpleDateFormat;
import java.util.Date;

public class MainActivity extends AppCompatActivity {

    private String EVENT_DATE_TIME = "2019-12-31 10:30:00";
    private String DATE_FORMAT = "yyyy-MM-dd HH:mm:ss";
    private LinearLayout linear_layout_1, linear_layout_2;
    private TextView tv_days, tv_hour, tv_minute, tv_second;
    private Handler handler = new Handler();
    private Runnable runnable;

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

        initUI();
        countDownStart();
    }

    private void initUI() {
        linear_layout_1 = findViewById(R.id.linear_layout_1);
        linear_layout_2 = findViewById(R.id.linear_layout_2);
        tv_days = findViewById(R.id.tv_days);
        tv_hour = findViewById(R.id.tv_hour);
        tv_minute = findViewById(R.id.tv_minute);
        tv_second = findViewById(R.id.tv_second);
    }

    private void countDownStart() {
        runnable = new Runnable() {
            @Override
            public void run() {
                try {
                    handler.postDelayed(this, 1000);
                    SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_FORMAT);
                    Date event_date = dateFormat.parse(EVENT_DATE_TIME);
                    Date current_date = new Date();
                    if (!current_date.after(event_date)) {
                        long diff = event_date.getTime() - current_date.getTime();
                        long Days = diff / (24 * 60 * 60 * 1000);
                        long Hours = diff / (60 * 60 * 1000) % 24;
                        long Minutes = diff / (60 * 1000) % 60;
                        long Seconds = diff / 1000 % 60;
                        //
                        tv_days.setText(String.format("%02d", Days));
                        tv_hour.setText(String.format("%02d", Hours));
                        tv_minute.setText(String.format("%02d", Minutes));
                        tv_second.setText(String.format("%02d", Seconds));
                    } else {
                        linear_layout_1.setVisibility(View.VISIBLE);
                        linear_layout_2.setVisibility(View.GONE);
                        handler.removeCallbacks(runnable);
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        };
        handler.postDelayed(runnable, 0);
    }

    protected void onStop() {
        super.onStop();
        handler.removeCallbacks(runnable);
    }
}
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activity_main.xml中

    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@android:color/white"
    android:orientation="horizontal">

    <LinearLayout
        android:id="@+id/linear_layout_1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@android:color/black"
        android:gravity="center_horizontal"
        android:visibility="gone">

        <TextView
            android:id="@+id/tv_event"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_margin="20dp"
            android:text="Android Event Start"
            android:textColor="@android:color/white"
            android:textSize="20dp"
            android:textStyle="normal" />
    </LinearLayout>

    <LinearLayout
        android:id="@+id/linear_layout_2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@android:color/black"
        android:visibility="visible">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:orientation="vertical">

            <TextView
                android:id="@+id/tv_days"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="00"
                android:textColor="@android:color/white"
                android:textSize="20dp"
                android:textStyle="bold" />

            <TextView
                android:id="@+id/tv_days_title"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="Days"
                android:textColor="@android:color/white"
                android:textSize="20dp"
                android:textStyle="normal" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:orientation="vertical">

            <TextView
                android:id="@+id/tv_hour"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="00"
                android:textColor="@android:color/white"
                android:textSize="20dp"
                android:textStyle="bold" />

            <TextView
                android:id="@+id/tv_hour_title"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="Hour"
                android:textColor="@android:color/white"
                android:textSize="20dp"
                android:textStyle="normal" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:orientation="vertical">

            <TextView
                android:id="@+id/tv_minute"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="00"
                android:textColor="@android:color/white"
                android:textSize="20dp"
                android:textStyle="bold" />

            <TextView
                android:id="@+id/tv_minute_title"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="Minute"
                android:textColor="@android:color/white"
                android:textSize="20dp"
                android:textStyle="normal" />
        </LinearLayout>

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:orientation="vertical">

            <TextView
                android:id="@+id/tv_second"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="00"
                android:textColor="@android:color/white"
                android:textSize="20dp"
                android:textStyle="bold" />

            <TextView
                android:id="@+id/tv_second_title"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:text="Second"
                android:textColor="@android:color/white"
                android:textSize="20dp"
                android:textStyle="normal" />
        </LinearLayout>
    </LinearLayout>
</LinearLayout>
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  • 一旦活动被破坏,不要忘记清理计时器.否则你将发送内存泄漏 (3认同)

小智 38

只需复制粘贴以下代码........

主要活动

package com.example.countdowntimer;

import java.util.concurrent.TimeUnit;
import android.app.Activity;
import android.os.Bundle;
import android.os.CountDownTimer;
import android.widget.TextView;


public class MainActivity extends Activity {


      TextView text1;

 private static final String FORMAT = "%02d:%02d:%02d";

 int seconds , minutes;

@Override
public void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);


    text1=(TextView)findViewById(R.id.textView1);

    new CountDownTimer(16069000, 1000) { // adjust the milli seconds here

        public void onTick(long millisUntilFinished) {

            text1.setText(""+String.format(FORMAT,
                    TimeUnit.MILLISECONDS.toHours(millisUntilFinished),
TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished) - TimeUnit.HOURS.toMinutes(
                    TimeUnit.MILLISECONDS.toHours(millisUntilFinished)),
  TimeUnit.MILLISECONDS.toSeconds(millisUntilFinished) - TimeUnit.MINUTES.toSeconds(
                      TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished))));              
        }

        public void onFinish() {
            text1.setText("done!");
        }
     }.start();             

  }

  }
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activity_main.xml中

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical" >

<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:layout_marginLeft="34dp"
    android:layout_marginTop="58dp"
    android:text="Large Text"
    android:textAppearance="?android:attr/textAppearanceMedium" />

   </RelativeLayout>
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  • 请不要鼓励复制粘贴代码.文档和解释的链接将是一个更好的答案. (7认同)
  • 但当我的手机锁定暂停时,当我解锁它将恢复...我能做什么继续计时器? (2认同)

Pra*_*dro 18

只需通过秒和textview对象调用以下函数

public void reverseTimer(int Seconds,final TextView tv){

    new CountDownTimer(Seconds* 1000+1000, 1000) {

        public void onTick(long millisUntilFinished) {
            int seconds = (int) (millisUntilFinished / 1000);
            int minutes = seconds / 60;
            seconds = seconds % 60;
            tv.setText("TIME : " + String.format("%02d", minutes)
                    + ":" + String.format("%02d", seconds));
        }

        public void onFinish() {
            tv.setText("Completed");
        }
    }.start();
}
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tej*_*hah 8

使用小时分钟和秒来重置CountDown计时器

public void reverseTimer(int Seconds, final TextView tv) {

    new CountDownTimer(Seconds * 1000 + 1000, 1000) {

        public void onTick(long millisUntilFinished) {
            int seconds = (int) (millisUntilFinished / 1000);

            int hours = seconds / (60 * 60);
            int tempMint = (seconds - (hours * 60 * 60));
            int minutes = tempMint / 60;
            seconds = tempMint - (minutes * 60);

            tv.setText("TIME : " + String.format("%02d", hours)
                    + ":" + String.format("%02d", minutes)
                    + ":" + String.format("%02d", seconds));
        }

        public void onFinish() {
            tv.setText("Completed");
        }
    }.start();
}
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Dan*_*erg 8

使用科特林:

var timer = object: CountDownTimer(30000, 1000) {
        override fun onTick(millisUntilFinished: Long) {
            tvTimer.setText("seconds remaining: " + millisUntilFinished / 1000)
        }

        override fun onFinish() {
            tvTimer.setText("done!")
        }
    }
timer.start()
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小智 6

输出:01:30

new CountDownTimer(90000, 1000) {

            public void onTick(long duration) {
                //tTimer.setText("seconds remaining: " + millisUntilFinished / 1000);
                //here you can have your logic to set text to edittext resource id
                // Duration
                long Mmin = (duration / 1000) / 60;
                long Ssec = (duration / 1000) % 60;
                if (Ssec < 10) {
                    tTimer.setText("" + Mmin + ":0" + Ssec);
                } else tTimer.setText("" + Mmin + ":" + Ssec);
            }

            public void onFinish() {
                tTimer.setText("00:00");
            }

        }.start();
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