Objective-C: dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{ // show loading }); Swift 3:(注意 :block里面不可省略self) DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 3) { // show loading }
Objective-C:
Swift 3:(注意 :block里面不可省略self)