一個定時迴圈任務的工具，可以用於執行每隔固定時間就要執行一次的任務。例如大圖輪播，狀態監測什麼的。

共有4個Java檔案。具體的使用方法在最下面。

Counter.java

package com.***.android.time;
import java.util.HashMap;
/**
 * Created by zpybless on 2015/11/18.
 */
public class Counter{

    static class CountableState {

        int count;
}


    //單例模式
private static Counter counter
 
;
    public static Counter getInstance() {
        if (counter == null) {
            counter = new Counter();
}
        return counter;
}


    private HashMap<ICountable, CountableState> states = new HashMap<ICountable, CountableState>();
//為每一個任務（使用同一個計時器）新增計數器，並啟動任務instance.onCountIncreasesToOne();
 
    //同一個TickTimer，呼叫多次start()的情況，計數器會增加
public void increase(ICountable instance) {

        CountableState state = states.get(instance);
        if (state == null) {
            state = new CountableState();
state.count = 1;
states.put(instance, state);
instance.onCountIncreasesToOne();
}
        else 
 
{
            state.count++;
}
    }

    //結束任務，計數器-1，如果是最後一個執行緒，就結束instance.onCountDecreasesToZero();;
public void decrease(ICountable instance) {

        CountableState state = states.get(instance);
state.count--;
        if (state.count == 0) {
            states.remove(instance);
instance.onCountDecreasesToZero();
}
    }

    public int getCount(ICountable instance) {
        CountableState state = states.get(instance);
        return state == null ? 0 : state.count;
}
}

package com.***.android.time;
/**
 * Created by zpybless on 2015/11/18. */
public interface ICountable {
    void onCountIncreasesToOne();
    void onCountDecreasesToZero();
}

TickTimer.java

package com.***.android.time;
import android.os.Handler;
/**
 * 計時器
* Created by zpybless on 2015/11/18.
 */
public class TickTimer implements ICountable {

    /**
     * 計時器對外介面，每隔一段時間，執行某一任務     * @param duration 時間間隔
* @param runnable 任務程序
*/
public TickTimer(TimeSpan duration, Runnable runnable) {
        this.duration = duration;
        this.runnable = runnable;
}


    private static int nextSessionID;
    private int sessionID;
    private TimeSpan duration;
    private boolean isRunning;
    public boolean isRunning() {
        return isRunning;
}

    private Runnable runnable;
    private static Handler handler = new Handler();
    private Runnable onTickRunnable;
//同一個TickTimer物件，對此呼叫此方法，onCountIncreasesToOne()只會被執行1次（第一次）
public void start() {
        Counter.getInstance().increase(this);
}

    public void stop() {
        Counter.getInstance().decrease(this);
}

    private void onTick() {

        if (runnable != null) {
            runnable.run();
}
    }

    @Override
public void onCountIncreasesToOne() {

        sessionID = nextSessionID;
nextSessionID++;
onTickRunnable = new Runnable() {

            public int sessionID = TickTimer.this.sessionID;
            public void run() {
                onTick();
                if (isRunning && sessionID == TickTimer.this.sessionID) {
                    //再次執行本執行緒，使onTick()裡面的執行緒任務達到迴圈執行的效果
handler.postDelayed(onTickRunnable, duration.getMilliseconds());
}
            }
        };
//執行緒開關
isRunning = true;
//啟動執行緒
onTickRunnable.run();
}

    @Override
public void onCountDecreasesToZero() {
        isRunning = false;
}
}

TimeSpan.java

package com.***.android.time;
/**時間相關工具類
* Created by zpybless on 2015/11/18.
 */
public class TimeSpan {

    private long milliseconds;
    public long getMilliseconds() {
        return milliseconds;
}

    public TimeSpan(long milliseconds) {
        this.milliseconds = milliseconds;
}

    public int getMillisecondPart() {
        return (int)(milliseconds % 1000);
}

    public int getSecondPart() {
        return getSecond(milliseconds);
}

    public int getMinutePart() {
        return getMinute(milliseconds);
}

    public int getHourPart() {
        return getHour(milliseconds);
}

    @Override
public String toString() {
        return getClockHmsString(milliseconds);
}


    public static String getClockHmsString(long milliseconds) {
        return String.format("%d:%02d:%02d", getHour(milliseconds), getMinute(milliseconds), getSecond(milliseconds));
}

    public static String getCounterHmsString(long milliseconds) {
        return String.format("%02d:%02d:%02d", getHour(milliseconds), getMinute(milliseconds), getSecond(milliseconds));
}

    private static int getHour(long milliseconds) {
        return (int)(Math.floor((float)milliseconds / (1000 * 60 * 60)));
}

    private static int getMinute(long milliseconds) {
        return (int)(Math.floor((float)milliseconds / (1000 * 60))) % 60;
}

    private static int getSecond(long milliseconds) {
        return (int)(Math.floor((float)milliseconds / 1000)) % 60;
}


    public static TimeSpan fromMilliseconds(float time) {
        return new TimeSpan((long)time);
}

    public static TimeSpan fromSeconds(float time) {
        return new TimeSpan((long)(time * 1000));
}

    public static TimeSpan fromMinutes(float time) {
        return new TimeSpan((long)(time * 1000 * 60));
}

    public static TimeSpan fromHours(float time) {
        return new TimeSpan((long)(time * 1000 * 60 * 60));
}

    public static TimeSpan fromDays(float time) {
        return new TimeSpan((long)(time * 1000 * 60 * 60 * 24));
}
}

具體使用：

TickTimer timer = new TickTimer(TimeSpan.fromSeconds(10.00f)【時間間隔】, new Runnable() {