ios之runloop筆記

網上關於runloop的文章不計其數，再此，貼個自認為講的比較簡單明了的文章

http://www.jianshu.com/p/536184bfd163

 

個人理解：

ios的runloop應該是類似於線程之間的消息監聽+隊列（隊列於外部不透明，支持多重send消息模式，perform selector，timer，UI事件等等）
和android的Looper非常相似，和windows的消息循環也很類似，具體底層實現不關注，直接貼測試代碼

 

#import "ViewController.h"

@interface ViewController ()

@property(nonatomic, strong) NSThread *thread;
@property(nonatomic, strong) NSThread *msgThread;

@end

@implementation ViewController

- (void) viewDidLoad{
    [super viewDidLoad];
    
    [self initMsgThread];
}

- (void) initMsgThread{
    
    self.msgThread = [[NSThread alloc]initWithTarget:self selector:@selector(msgThreadInitFunc) object:nil];
    [self.msgThread start];
}

- (void) msgThreadInitFunc{
    NSLog(@"msgThreadInitFunc run, %@",[NSThread currentThread]);
    
    [[NSRunLoop currentRunLoop] addPort:[[NSPort alloc] init] forMode:NSDefaultRunLoopMode];
    [[NSRunLoop currentRunLoop] run];
    
    NSLog(@"msgThreadInitFunc run");
    
}

//******************************************************************************************************************
- (void) postMsgToThread{
    [[[NSThread alloc]initWithTarget:self selector:@selector(asyncPostMsgToThread) object:nil] start];
}

- (void) asyncPostMsgToThread{
    [self performSelector:@selector(onThreadMsgProc) onThread:self.msgThread withObject:nil waitUntilDone:NO];
}

- (void) onThreadMsgProc{
    NSLog(@"do some work %@, %s", [NSThread currentThread], __FUNCTION__);
}

//******************************************************************************************************************
- (void) startTimerOnThread{
    self.thread = [[NSThread alloc]initWithTarget:self selector:@selector(asyncStartTimerOnThread) object:nil];
    [self.thread start];
}

- (void) asyncStartTimerOnThread{
    [self performSelector:@selector(asyncStartTimer) onThread:self.thread withObject:nil waitUntilDone:NO];
    
//    [[NSRunLoop currentRunLoop] addPort:[[NSPort alloc] init] forMode:NSDefaultRunLoopMode];
    [[NSRunLoop currentRunLoop] run];
}

- (void) asyncStartTimer{
    [NSTimer scheduledTimerWithTimeInterval:3.0 target:self selector:@selector(timerFired:)userInfo:nil repeats:YES];
}

- (void) timerFired:(id)timer{
    NSLog(@"on thread timer %s",__FUNCTION__);
}

//******************************************************************************************************************
- (IBAction)testButtonTapped:(id)sender {
//    [self postMsgToThread];
    [self startTimerOnThread];
}

@end

當然用block也是一樣的，子線程必須創建runloop來監聽消息，否則這個子線程是無法處理類似performSelector，NSTimer之類的消息的

線程之間通信，cocos2dx，u3d，ios，android，win32，都是基於消息隊列的模式，一個發，一個收，寫時加鎖，別無更好的辦法了