Android(安卓)定时／倒计时工具 - 加强版 CountDownTimer - android

作用

轻量级的 Android 定时／倒计时工具。

使用方法

start()
开始倒计时
stop()
停止倒计时
pause()
暂停倒计时
restart()
继续暂停的倒计时
onTick()
倒计时间隔回调
onFinish()
倒计时结束回调
CustomCountDownTimer(long millisInFuture, long countDownInterval)
构造方法，其中参数的含义：
millisInFuture: 总时长
countDownInterval: 间隔时长

例如，CustomCountDownTimer(10000， 1000) 表示从现在开始倒计时，10秒后结束，每秒触发一次 onTick 事件。注意：onTick 事件在每秒的开始时刻调用，即 “onTick - 1秒“ – “onTick - 1秒“……如此重复10次。

源码

import android.os.Handler;import android.os.Message;import android.os.SystemClock;/** * 使用 android.os.CountDownTimer 的源码 * 1. 对回调 onTick 做了细小调整，已解决最后1秒不会倒计时到0，要等待2秒才回调 onFinish * 2. 添加了一些自定义方法 * Created by iWgang on 15/10/18. * https://github.com/iwgang/CountdownView */public abstract class CustomCountDownTimer {    private static final long ONE_SECOND_MILLS = 1000L;    private static final long CORRECT_OFFSET = 15L;    private static final int MSG = 1;    private final long mMillisInFuture;    private final long mCountdownInterval;    private long mStopTimeInFuture;    private long mPauseTimeInFuture;    private boolean isStop = false;    private boolean isPause = false;    /**     * @param millisInFuture    总倒计时时间     * @param countDownInterval 倒计时间隔时间     */    public CustomCountDownTimer(long millisInFuture, long countDownInterval) {        // 解决秒数有时会一开始就减去了2秒问题（如10秒总数的，刚开始就8999，然后没有不会显示9秒，直接到8秒）        if (countDownInterval > ONE_SECOND_MILLS) {            millisInFuture += CORRECT_OFFSET;        }        mMillisInFuture = millisInFuture;        mCountdownInterval = countDownInterval;    }    private synchronized CustomCountDownTimer start(long millisInFuture) {        isStop = false;        if (millisInFuture <= 0) {            onFinish();            return this;        }        mStopTimeInFuture = SystemClock.elapsedRealtime() + millisInFuture;        mHandler.sendMessage(mHandler.obtainMessage(MSG));        return this;    }    /**     * 开始倒计时     */    public synchronized final void start() {        start(mMillisInFuture);    }    /**     * 停止倒计时     */    public synchronized final void stop() {        isStop = true;        mHandler.removeMessages(MSG);    }    /**     * 暂时倒计时     * 调用{@link #restart()}方法重新开始     */    public synchronized final void pause() {        if (isStop) return;        isPause = true;        mPauseTimeInFuture = mStopTimeInFuture - SystemClock.elapsedRealtime();        mHandler.removeMessages(MSG);    }    /**     * 重新开始     */    public synchronized final void restart() {        if (isStop || !isPause) return;        isPause = false;        start(mPauseTimeInFuture);    }    /**     * 倒计时间隔回调     *     * @param millisUntilFinished 剩余毫秒数     */    public abstract void onTick(long millisUntilFinished);    /**     * 倒计时结束回调     */    public abstract void onFinish();    private Handler mHandler = new Handler() {        @Override        public void handleMessage(Message msg) {            synchronized (CustomCountDownTimer.this) {                if (isStop || isPause) {                    return;                }                final long millisLeft = mStopTimeInFuture - SystemClock.elapsedRealtime();                if (millisLeft <= 0) {                    onFinish();                }                else {                    long lastTickStart = SystemClock.elapsedRealtime();                    onTick(millisLeft);                    // take into account user's onTick taking time to execute                    long delay = lastTickStart + mCountdownInterval - SystemClock.elapsedRealtime();                    // special case: user's onTick took more than interval to                    // complete, skip to next interval                    while (delay < 0) delay += mCountdownInterval;                    sendMessageDelayed(obtainMessage(MSG), delay);                }            }        }    };}

Android(安卓)定时／倒计时工具 - 加强版 CountDownTimer

作用

使用方法

源码

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