IOS6.0 应用内直接下载程序 不需跳转AppStore -b

闲来没事看了篇文章 应用内创建应用商店环境，不跳转AppStore. 先武断的想一句：放屁。然后好奇的进去看看，原来是IOS6.0的新特性，顿感惭愧。研究下

SKStoreProductViewController类是UIViewController的子类, 如果你对view controller比较熟悉的话，那SKStoreProductViewController使用起来也非常简单了。当你希望向用户展示App Store中产品时，你需要：

1.实例化一个SKStoreProductViewController类
2.设置它的delegate
3.把sotre product视图控制器显示给消费者

剩下的就交给操作系统来处理了。需要记住一点的是SKStoreProductViewController只能以模态的方式显示。SKStoreProductViewControllerDelegate协议定义了一个单独的方法—productViewControllerDidFinish:，当消费者离开App Store时会调用这个方法—一般是通过点击左上角画面中的取消按钮。通过给代理发送productViewControllerDidFinish:消息，操作系统就会把控制权返回到你的程序。当然你不能忘了 只支持IOS6.0及其以上~~

步骤：

1.添加 storeKit.framework

2.头文件里 加上  

#import 

@interface ViewController : UIViewController<</span>SKStoreProductViewControllerDelegate>

3.直接在m中实现

- (IBAction)doAction:(UIButton *)sender {
      [self showAppInApp:@"xxxxxx"];//此处xxxxx需要替换为需要的appID
}
- (void)showAppInApp:(NSString *)_appId {
  Class isAllow = NSClassFromString(@"SKStoreProductViewController");
  if (isAllow != nil) {
    SKStoreProductViewController *sKStoreProductViewController = [[SKStoreProductViewController alloc] init];
    sKStoreProductViewController.delegate = self;
    [sKStoreProductViewController loadProductWithParameters:@{SKStoreProductParameterITunesItemIdentifier: _appId}
                      completionBlock:^(BOOL result, NSError *error) {
                        if (result) {
                          [self presentViewController:_SKSVC
                                             animated:YES
                                           completion:nil];
                        }
                        else{
                          NSLog(@"%@",error);
                        }
                      }];
  }
  else{
    //低于iOS6没有这个类
    NSString *string = [NSString stringWithFormat:@"itms-apps://itunes.apple.com/us/app/id%@?mt=8",_appId];
    [[UIApplication sharedApplication] openURL:[NSURL URLWithString:string]];
  }
}

#pragma mark - SKStoreProductViewControllerDelegate 

//对视图消失的处理
- (void)productViewControllerDidFinish:(SKStoreProductViewController *)viewController {

  [viewController dismissViewControllerAnimated:YES
                                     completion:nil];

}