How to open multithreading

Methods for creating threads

Nsthread

Nsoperationqueue and Nsoperation

GCD

Executing code in the main thread

[Self performSelectorOnMainThread:withObject:waitUntilDone:];

[Self performselector:onthread:[nsthread mainthread] Withobject:waituntildone:];

Dispatch_async (Dispatch_get_main_queue (), ^{

});

Delay execution

Double delayinseconds = 2.0;

dispatch_time_t poptime = Dispatch_time (Dispatch_time_now,

(int64_t) (Delayinseconds * nsec_per_sec));

Dispatch_after (Poptime, Dispatch_get_main_queue (), ^ (void) {

});

[Self performSelector:withObject:afterDelay:];

[Nstimer scheduledTimerWithTimeInterval:target:selector:userInfo:repeats:];

Loadview

When using the controller's view for the first time, the Loadview method is called to create the view

In general, customize the view here

When the controller view is used for the first time, it is called

Viewdidload

Called when the controller's view is created, that is, after Loadview

It is common to add child controls, initialize data

Viewdidunload

Called when the controller's view is destroyed because of a memory warning

Usually here to recycle the interface-related resources (the interface will be destroyed, and interface-related resources must not be)

How to open multithreading