iphone – 如何在视图中显示加载动画 – IOS

#import <UIKit/UIKit.h>;
#import "MBProgressHUD.h" // import the .h file into project.
@class MBProgressHudDemoViewController;

@interface MBProgressHudDemoAppDelegate : NSObject <UIApplicationDelegate,MBProgressHUDDelegate> {
    UIWindow *window;
    MBProgressHudDemoViewController *viewController;
        MBProgressHUD *HUD;// create the object of Hud.
}

@property (nonatomic,retain) IBOutlet UIWindow *window;
@property (nonatomic,retain) IBOutlet MBProgressHudDemoViewController *viewController;


-(void)showProgressHUD:(NSString*)msg;
-(void)hideProgressHUD;
@end

#import &lt;UIKit/UIKit.h&gt;
#import "MBProgressHudDemoAppDelegate.h"
@interface MBProgressHudDemoViewController : UIViewController {
    MBProgressHudDemoAppDelegate *delegate;
}

@end

ViewControll.m文件

#import "MBProgressHudDemoViewController.h"
#import "MBProgressHudDemoAppDelegate.h"
@implementation MBProgressHudDemoViewController

// Implement viewDidLoad to do additional setup after loading the view,typically from a nib.
- (void)viewDidLoad {
    [super viewDidLoad];

        [self performSelector:@selector(nextDetail)  withObject:nil afterDelay:2]; 

}
-(void)nextDetail{
    delegate = (MBProgressHudDemoAppDelegate*)[[UIApplication sharedApplication] delegate];
    [delegate showProgressHUD:@"Please Wait..."];
        [self performSelector:@selector(RemoveHud)  withObject:nil afterDelay:2]; 
}
-(void)RemoveHud{
    [delegate hideProgressHUD];
}
@end

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