1.首先我们如果要做这个效果就要知道这个(UIDocumentInteractionController）
_docController = [UIDocumentInteractionController interactionControllerWithURL:[NSURL fileURLWithPath:[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)[0] stringByAppendingPathComponent:@"123.xls"]]];
_docController.delegate = self;
[_docController presentOpenInMenuFromRect:CGRectMake(760, 20, 100, 100) inView:self.view animated:YES];
2.重中之重我们要把他的代理写上，要不然会把你崩的细碎的，哈哈
- (UIViewController *)documentInteractionControllerViewControllerForPreview:(UIDocumentInteractionController *)controller
{
return self;
}
- (UIView *)documentInteractionControllerViewForPreview:(UIDocumentInteractionController *)controller
{
return self.view;
}
- (CGRect)documentInteractionControllerRectForPreview:(UIDocumentInteractionController *)controller
{
return self.view.frame;
}
3.如果完成了这2步基本了然了，但是还有记得自己去把代里协议 写上啊
算了还是我也给你写了吧。。。
<UIDocumentInteractionControllerDelegate>
@property(nonatomic,retain)UIDocumentInteractionController *docController;
4.完成了黄金三步 还不成功。
下载文件 ，调用系统的方法(UIDocumentInteractionController) 查看
原文：http://www.cnblogs.com/yuejunjie/p/4976852.html