Android 倒計時器

Android 中好像沒有提供類似的工具可以使用，這裡實現一個到計時器.提供兩個回調接口

1. interface OnCountDownListener
2. {
3. void OnCountDownTimeout(); // 倒計時完成
4. void onCountDownIntervalReach(int last); // 倒計時時間時間間隔到達、用於過程中需要刷新的部分，last為已經過去多少時間
5. }

完整源碼：

1. package com.example.countdown;
3. import java.lang.ref.WeakReference;
5. import android.os.Handler;
6. import android.os.Message;
8. public class CountDown {
10. private final static int TAG_COUNT_DOWN_INTERVAL_REACH = 0x100;
11. private final static int TAG_COUNT_DOWN_TIMEOUT = 0x101;
13. private int mTimeout;
14. private int mInterval;
15. private int mCount;
16. private CountDownHandler mHandler;
17. private CountDownThread mThread;
18. private OnCountDownListener mListener;
19. private boolean mToQuit = false;
21. CountDown(int timeout, int interval){
22. mTimeout = timeout;
23. mInterval = interval <= 0 ? 10 : interval;
24. mCount = 0;
25. mHandler = new CountDownHandler(this);
26. }
28. public void setOnCountDownListener(OnCountDownListener listener){
29. mListener = listener;
30. }
32. public void start(){
33. mToQuit = false;
34. mCount = 0;
35. mThread = new CountDownThread();
36. mThread.start();
37. }
39. public void stop(){
40. mToQuit = true;
41. if( mThread != null ) mThread.interrupt();
42. }
44. private static class CountDownHandler extends Handler
45. {
46. WeakReference<CountDown> mRef;
48. CountDownHandler(CountDown countdown){
49. mRef = new WeakReference<CountDown>(countdown);
50. }
52. public void handleMessage(Message msg)
53. {
54. CountDown countDown = mRef.get();
55. switch (msg.what)
56. {
57. case TAG_COUNT_DOWN_INTERVAL_REACH:
58. if( countDown.mListener != null )
59. countDown.mListener.onCountDownIntervalReach((Integer)msg.obj);
60. break;
61. case TAG_COUNT_DOWN_TIMEOUT:
62. if( countDown.mListener != null )
63. countDown.mListener.OnCountDownTimeout();
64. break;
65. default:
66. break;
67. }
68. super.handleMessage(msg);
69. }
70. }
72. private class CountDownThread extends Thread{
73. public void run()
74. {
75. while( ! isInterrupted() ){
76. try {
77. Thread.sleep(mInterval);
78. mCount++;
80. Message message = new Message();
81. if( mCount * mInterval > mTimeout ){
82. message.what = TAG_COUNT_DOWN_TIMEOUT;
83. mHandler.sendMessage(message);
84. break;
85. }
87. message.what = TAG_COUNT_DOWN_INTERVAL_REACH;
88. message.obj = mCount * mInterval;
89. mHandler.sendMessage(message);
90. } catch (InterruptedException e) {
91. e.printStackTrace();
92. if( mToQuit ) break;
93. }
94. }
95. }
96. }
98. interface OnCountDownListener{
99. void OnCountDownTimeout();
100. void onCountDownIntervalReach(int last);
101. }
102. }