应用程序程序启动时加载广告 ---ios

@interface ABADViewController ()
@property (weak, nonatomic) IBOutlet UIButton *ADJumpBtn;
//跳过 按钮
@property (weak, nonatomic) IBOutlet UIImageView *ADImageView;
//加载界面的图片
@property (weak, nonatomic) IBOutlet UIView *ADView;
@property (nonatomic, weak) UIImageView *imageView;
//加载广告的图片
@property (nonatomic, strong) ABADModel *model;
@property (nonatomic, weak) NSTimer *timer;


@end

@implementation ABADViewController
- (UIImageView *)imageView{
    if (_imageView == nil) {
        UIImageView *imageView = [[UIImageView alloc] init];
        _imageView = imageView;
        [self.ADView addSubview:imageView];
        _imageView.userInteractionEnabled = YES;
        UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tap)];
//添加手势
        [imageView addGestureRecognizer:tap];
        
    }
    return _imageView;
}
- (void)tap{
    UIApplication *app = [UIApplication sharedApplication];
    if ([app canOpenURL:[NSURL URLWithString:@"http://sina.cn/?wm=4007"]]) {

        [app openURL:[NSURL URLWithString:@"http://sina.cn/?wm=4007"]];
    }
}
- (void)viewDidLoad {
    [super viewDidLoad];
    [self setLau];
    [self loadData];
    _timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(changeTime) userInfo:nil repeats:YES];
//添加定时器，倒数时间

}
- (void)setLau{
    self.ADImageView.image = [UIImage imageNamed:@"LaunchImage-568h"];

}
- (void)loadData{
  //利用sdImage框架异步下载广告界面 赋值与self.imageView  
}
- (IBAction)ADBtnClick:(id)sender {
    UIApplication *app = [UIApplication sharedApplication];
    app.keyWindow.rootViewController = [[ABTBController alloc] init];
    [_timer invalidate];
//销毁定时器，否则不会释放
}
- (void)changeTime{
    static int time =3;
    if (time  <= 0 ){
        [self ADBtnClick:nil];
    }
    time--;
    NSString *str = [NSString stringWithFormat:@"跳过 %d秒",time];
    [self.ADJumpBtn setTitle:str forState:UIControlStateNormal];
//利用定时器倒数时间，时间结束触发按钮事件
}