iOS Development multithreaded article-Creating threads

I. Simple instructions for creating and starting a thread

A Nsthread object represents a thread

Creating, starting Threads

(1) nsthread *thread = [[Nsthread alloc] initwithtarget:self selector: @selector (run) Object:nil];

[Thread start];

When a thread is started, the run method of self is executed in threads thread

Main thread related usage

+ (Nsthread *) Mainthread; Get the main thread

-(BOOL) Ismainthread; is the main thread

+ (BOOL) Ismainthread; is the main thread

Other usage

Get current thread

Nsthread *current = [Nsthread CurrentThread];

Scheduling priority for a thread: The value of the scheduling priority is 0.0 ~ 1.0, the default is 0.5, the higher the value, the greater the priority

+ (double) threadpriority;

+ (BOOL) SetThreadPriority: (double) p;

Set the name of the thread

-(void) SetName: (NSString *) n;

-(NSString *) name;

Other ways to create threads

(2) automatically start thread after creating thread

[Nsthread detachnewthreadselector: @selector (Run) totarget:self Withobject:nil];

(3) implicitly creating and starting threads

[Self Performselectorinbackground: @selector (Run) Withobject:nil];

Pros and cons of the above 2 ways to create threads

Advantages: Simple and fast

Cons: Unable to set the thread in more detail

Second, code example

1. Create it in an ancient way

1 //2 //YYVIEWCONTROLLER.M3 //4 //5 //Created by Apple on 14-6-23.6 //Copyright (c) 2014 itcase. All rights reserved.7 //8 9 Ten #import "YYViewController.h" One #import<pthread.h> A  -  - @interfaceYyviewcontroller () the-(ibaction) Btnclick; - @end -   -  + @implementationYyviewcontroller -   +  A- (void) Viewdidload at { - [Super Viewdidload]; - } -  -   - //button's Click event in-(ibaction) Btnclick { -     //1. Get the current thread toNsthread *current=[Nsthread CurrentThread]; +     //Main Thread -NSLog (@"btnclick----%@", current);  the  *     //2. Use a For loop to perform some time-consuming operations $ pthread_t thread;Panax NotoginsengPthread_create (&thread, NULL, run, NULL); - } the  +  A //C language Functions the void*run (void*data) + { -     //gets the current thread, which is the newly created thread $Nsthread *current=[Nsthread CurrentThread]; $  -  -      for(intI=0; i<10000; i++) { theNSLog (@"Btnclick---%d---%@", i,current); -     }Wuyi     returnNULL; the } -  Wu //multiple threads, the main thread is not blocked when you click the button to execute the button call method -  About @end

Implementation results:

Printing results:

2. Create a thread using Nsthread

1 //2 //YYVIEWCONTROLLER.M3 //4 //5 //Created by Apple on 14-6-23.6 //Copyright (c) 2014 itcase. All rights reserved.7 //8 9 #import "YYViewController.h"Ten #import<pthread.h> One  A  - @interfaceYyviewcontroller () --(ibaction) Btnclick; the @end -  -  - @implementationYyviewcontroller +  -- (void) Viewdidload + { A [Super Viewdidload]; at } -  -  - //button's Click event --(ibaction) Btnclick { -     //1. Get the current thread inNsthread *current=[Nsthread CurrentThread]; -     //Main Thread toNSLog (@"btnclick----%@", current); +  -     //another way to get the main thread theNsthread *main=[Nsthread Mainthread]; *NSLog (@"main thread-------%@", main); $ Panax Notoginseng     //2. Take some time-consuming actions - [self creatnsthread]; the //[self creatNSThread2]; + //[self creatNSThread3]; A } the  +   - /** $ * Nsthread Create thread mode 1 $ * 1> Create initialization thread first - * 2> start open thread -  */ the-(void) Creatnsthread - {WuyiNsthread *thread=[[nsthread alloc] initwithtarget:self selector: @selector (run:)Object:@"Thread A"]; the     //set a name for a thread -Thread.name=@"Thread A"; Wu      //Open Thread - [Thread start]; About    $  -Nsthread *thread2=[[nsthread alloc] initwithtarget:self selector: @selector (run:)Object:@"thread B"]; -     //set a name for a thread -Thread2.name=@"thread B"; A    //Open Thread + [thread2 start]; the } -  $   the /** the * Nsthread Create thread mode 2 the * Create thread Direct (auto) Start the  */ --(void) CreatNSThread2 in { the //nsthread *thread=[nsthread detachnewthreadselector: @selector (run:) totarget:self withobject:@ "Create thread Direct (auto) Start"] ; the  About[Nsthread detachnewthreadselector: @selector (run:) totarget:self Withobject:@"Direct (automatic) startup of the thread after creation"]; the } the  the  + /** - * Nsthread Create thread mode 3 the * Implicit creation of threads, and direct (automatic) Start-upBayi  */ the-(void) CreatNSThread3 the { -     //execute in a background thread = = = in a child thread -[Self Performselectorinbackground: @selector (run:) Withobject:@"implicitly-created"]; the } the  the  the  --(void) Run: (NSString *) Str the { the    //gets the current thread theNsthread *current=[Nsthread CurrentThread];94     //Print Output the      for(intI=0; i<Ten; i++) { theNSLog (@"Run---%@---%@", current,str); the     }98 } About @end

Call Thread 1 and print the result:

Calling thread 2

Calling thread 3

iOS Development multithreaded article-Creating threads