iOS 点击按钮增加加载中视图

点击按钮出现加载中；

UIViewcontroller 增加blockUIView ，backView ，UIActivityIndicatorView；

bringSubviewToFront 方法解决；

效果图：

#import <UIKit/UIKit.h>

@interface BaseViewController : UIViewController

@property (nonatomic,assign) BOOL isLogin;
@property (nonatomic,strong) UIView *blockView;
@property (nonatomic,strong) UIView *backView;
@property (nonatomic,strong) UIActivityIndicatorView *indicatorView;

- (void) gotoLogin;

//设置屏幕加载中
-(void) showBlockView;
//取消屏幕加载中
-(void) hideBlockView;

@end

</pre><pre name="code" class="objc">实现

<pre name="code" class="objc">@implementation BaseViewController

- (void) gotoLogin{

SecondController *loginVC = [[SecondController alloc] init];
[self.navigationController pushViewController:loginVC animated:YES];

}

-(void) viewDidLoad{

[self addBlockView];
}

-(void) addBlockView{

_blockView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)];
NSLog(@"self view width %.f",self.view.frame.size.width);
NSLog(@"self view width %.f",self.view.frame.size.height);
[_blockView setBackgroundColor:[UIColor grayColor]];
_blockView.alpha = 0.7f;

_backView =[[UIView alloc] initWithFrame:CGRectMake(_blockView.center.x-25, _blockView.center.y-25, 50, 50)];
[_backView setBackgroundColor:[UIColor blackColor]];
[_blockView addSubview:_backView];

_indicatorView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhite];
_indicatorView.frame = CGRectMake(_backView.center.x - 22.5, _backView.center.y - 22.5, 45, 45);
_indicatorView.hidesWhenStopped = YES;

[_blockView addSubview: _indicatorView];

[self.view addSubview:_blockView];
[_blockView setHidden:YES];

}

-(void) showBlockView{

[_indicatorView startAnimating];
[_blockView setHidden:NO];
[self.view bringSubviewToFront:_blockView];

}

-(void) hideBlockView{

[_indicatorView stopAnimating];
[_blockView setHidden:YES];

}