android倒计时控件示例

/*
 * Copyright (C) 2012 The * Project
 * All right reserved.
 * Version 1.00 2012-2-11
 * Author veally@foxmail.com
 */
package com.ly.sxh.view;
 
import android.content.Context;
import android.database.ContentObserver;
import android.os.Handler;
import android.os.SystemClock;
import android.provider.Settings;
import android.util.AttributeSet;
import android.widget.DigitalClock;
 
import java.util.Calendar;
 
/**
 * Custom digital clock
 * 倒计时控件
 *
 * @author
 */
public class CustomDigitalClock extends DigitalClock {
 
  Calendar mCalendar;
  private final static String m12 = "h:mm aa";
  private final static String m24 = "k:mm";
  private FormatChangeObserver mFormatChangeObserver;
 
  private Runnable mTicker;
  private Handler mHandler;
  private long endTime;
  private ClockListener mClockListener;
 
  private boolean mTickerStopped = false;
 
  @SuppressWarnings("unused")
  private String mFormat;
 
  public CustomDigitalClock(Context context) {
    super(context);
    initClock(context);
  }
 
  public CustomDigitalClock(Context context, AttributeSet attrs) {
    super(context, attrs);
    initClock(context);
  }
 
  private void initClock(Context context) {
 
    if (mCalendar == null) {
      mCalendar = Calendar.getInstance();
    }
 
    mFormatChangeObserver = new FormatChangeObserver();
    getContext().getContentResolver().registerContentObserver(Settings.System.CONTENT_URI, true, mFormatChangeObserver);
 
    setFormat();
  }
 
  @Override
  protected void onAttachedToWindow() {
    mTickerStopped = false;
    super.onAttachedToWindow();
    mHandler = new Handler();
 
    /**
     * requests a tick on the next hard-second boundary
     */
    mTicker = new Runnable() {
      public void run() {
        if (mTickerStopped)
          return;
        long currentTime = System.currentTimeMillis();
        if (currentTime / 1000 == endTime / 1000 - 5 * 60) {
          mClockListener.remainFiveMinutes();
        }
        long distanceTime = endTime - currentTime;
        distanceTime /= 1000;
        if (distanceTime == 0) {
          setText("00:00:00");
          onDetachedFromWindow();
          mClockListener.timeEnd();
        } else if (distanceTime < 0) {
          setText("00:00:00");
        } else {
          setText(dealTime(distanceTime));
        }
        invalidate();
        long now = SystemClock.uptimeMillis();
        long next = now + (1000 - now % 1000);
        mHandler.postAtTime(mTicker, next);
      }
    };
    mTicker.run();
  }
 
  /**
   * deal time string
   *
   * @param time
   * @return
   */
  public static String dealTime(long time) {
    StringBuffer returnString = new StringBuffer();
    long day = time / (24 * 60 * 60);
    long hours = (time % (24 * 60 * 60)) / (60 * 60);
    long minutes = ((time % (24 * 60 * 60)) % (60 * 60)) / 60;
    long second = ((time % (24 * 60 * 60)) % (60 * 60)) % 60;
    String dayStr = String.valueOf(day);
    String hoursStr = timeStrFormat(String.valueOf(hours));
    String minutesStr = timeStrFormat(String.valueOf(minutes));
    String secondStr = timeStrFormat(String.valueOf(second));
 
    returnString.append(hoursStr).append(":").append(minutesStr).append(":").append(secondStr);
    return returnString.toString();
  }
 
  /**
   * format time
   *
   * @param timeStr
   * @return
   */
  private static String timeStrFormat(String timeStr) {
    switch (timeStr.length()) {
      case 1:
        timeStr = "0" + timeStr;
        break;
    }
    return timeStr;
  }
 
  @Override
  protected void onDetachedFromWindow() {
    super.onDetachedFromWindow();
    mTickerStopped = true;
  }
 
  /**
   * Clock end time from now on.
   *
   * @param endTime
   */
  public void setEndTime(long endTime) {
    this.endTime = endTime;
  }
 
  /**
   * Pulls 12/24 mode from system settings
   */
  private boolean get24HourMode() {
    return android.text.format.DateFormat.is24HourFormat(getContext());
  }
 
  private void setFormat() {
    if (get24HourMode()) {
      mFormat = m24;
    } else {
      mFormat = m12;
    }
  }
 
  private class FormatChangeObserver extends ContentObserver {
    public FormatChangeObserver() {
      super(new Handler());
    }
 
    @Override
    public void onChange(boolean selfChange) {
      setFormat();
    }
  }
 
  public void setClockListener(ClockListener clockListener) {
    this.mClockListener = clockListener;
  }
 
  public interface ClockListener {
    void timeEnd();
 
    void remainFiveMinutes();
  }
 
}