iOS development easy to implement background tasks (such as background play music, timers, background positioning, etc.)

The maximum length of time to run, not to challenge the limit, how long it takes to keep the test.

Note: Test with a real machine

Directly on the code

In the Appdelegate. m, add some code actions when you enter the background

2. /**
4. * Called when the app enters the background
6. */
8. -(void) Applicationdidenterbackground: (uiapplication *) application
10. {
12. /** 
14. * Status of App
16. * 1. Death Status: No app opened
18. * 2. Foreground operation status
20. * 3. Background suspend state: Stop all animations, timers, multimedia, networking operations, it is difficult to do other operations
22. * 4. Background running status
24. */
26. //to the operating system to apply for background running qualification, how long can be maintained, is uncertain
28. Self.task = [Application beginbackgroundtaskwithexpirationhandler:^{
30. When the background run time for the application has ended (expired), the block is called
32. //
34. Finish the mission.
36. [Application EndBackgroundTask:self.task];
38. //    }];
40. __block uibackgroundtaskidentifier task = [Application beginbackgroundtaskwithexpirationhandler:^{
42. //When the background run time of the application has ended (expired), the block will be called
46. //Hurry to finish the task
48. [Application Endbackgroundtask:task];
50. }];
54. /** 
56. 1. Defining Variables Uibackgroundtaskidentifier Task
58. 2. Execute the code on the right
60. [Application beginbackgroundtaskwithexpirationhandler:^{
62. When the background run time for the application has ended (expired), the block is called
66. Finish the mission.
68. [Application Endbackgroundtask:task];
70. }];
72. 3. Assign the return value of the right method to a task
74. */
80. //Set background mode in INFO.PLST: Required background modes = = APP plays audio or streams audio/video using AirPlay
82. //engage in a 0kb MP3 file with no sound
84. //Loop playback
88. //Previous background mode has only 3 kinds
90. //Maintain network connectivity
92. //Multimedia Applications
94. //VOIP: Internet telephony
96. }

iOS development easy to implement background tasks (such as background play music, timers, background positioning, etc.)