develop_csdn的博客

1.创建static dispatch_source_t _reconTimer;dispatch_source_cancel(_timer);        NSTimeInterval period =5; //设置时间间隔        dispatch_queue_t queue =dispatch_get_global_queue(DISPATCH_QUEUE

建议换一下方式，亲测有效 AVPlayerItem *item = [AVPlayerItemplayerItemWithURL:[[NSBundlemainBundle] URLForResource:@"q1111.mp4"withExtension:nil]];        // 3.创建AVPlayer    _player = [AVPlayer

异步请求的返回先后顺序没有一定，很可能后发出的请求先返回；但是最后回调的时候，请求返回的结果必须要按请求发出的顺序排列。比如，一个很常见的处理是，上传图片的接口返回该图片的 url；那么回调结果里的 url 顺序显然需要跟上传的图片顺序一一对应上。为此提出一个解决方案，方法很多，本文使用GCD解决- (NSURLSessionUploadTask*)uploadTaskWith

2017-05-09 10:30:51.969437+0800 [35586:2135000] [LayoutConstraints] Unable to simultaneously satisfy constraints.Probably at least one of the constraints in the following list is one you don't want.

//计算缓存大小-(NSString*)getCacheSize{   //定义变量存储总的缓存大小   long long sumSize =0;      //获取当前图片缓存路径   NSString *cacheFilePath = [NSHomeDirectory()stringByAppendingPa

- (BOOL)canPerformAction:(SEL)action withSender:(id)sender{    NSLog(@"%@", NSStringFromSelector(action));    return YES;} - (BOOL)canPerformAction:(SEL)action withSender:(id)s

+ (NSString *)startTime:(NSString *)startTime endTime:(NSString*)endTime{   NSString *startTimeStr = [[NSStringalloc]init];   NSString *endTimeStr = [[NSStringalloc]init];   NSIn

什么情况使用 weak 关键字？在 ARC 中,在有可能出现循环引用的时候,往往要通过让其中一端使用 weak 来解决,比如: delegate 代理属性自身已经对它进行一次强引用,没有必要再强引用一次,此时也会使用 weak,自定义 IBOutlet 控件属性一般也使用 weak；当然，也可以使用strong。不同点：     weak 此特质表明该属性定义了

CABasicAnimation* rotationAnimation;    rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation"];    rotationAnimation.toValue = [NSNumbernumberWithFloat: M_PI

- (UIActivityIndicatorView*)activityIndicatorView{   if (!_activityIndicatorView) {       _activityIndicatorView = [[UIActivityIndicatorViewalloc]init];       _activityIndicatorVie

#define pixelValue(number) (number) / 750.0 * [[UIScreen mainScreen] bounds].size.width以6的屏幕为准

-fno-objc-arc

if (_cycleEndTf.text.length != 0) {            NSDate *currentDate = [NSDate date];            NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];            [dateFormat

UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0,0,100,100)]; imageView.center =CGPointMake(200,300); UIImage *anotherImage = [UIImage imageNamed:@"imag

- (void)viewDidLoad{[super viewDidLoad];//添加显示UIImage *image = [UIImage imageNamed:@"0_wanggsx20080817.jpg"];UIImageView *imageView = [[UIImageView alloc]initWithImage:image];imageView.fra

UIBlurEffect *blur = [UIBlurEffecteffectWithStyle:UIBlurEffectStyleLight];       UIVisualEffectView *effectview = [[UIVisualEffectViewalloc] initWithEffect:blur];        effectview.fra

dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,0);   dispatch_async(queue, ^{       NSURLRequest *request =[NSURLRequestrequestWithURL:[NSURLURL