iOS7適配

#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 70000 
    if ( IOS7_OR_LATER ) 
    { 
        self.edgesForExtendedLayout = UIRectEdgeNone;
        self.extendedLayoutIncludesOpaqueBars = NO;
        self.modalPresentationCapturesStatusBarAppearance = NO; 
    } 
#endif  // #if __IPHONE_OS_VERSION_MAX_ALLOWED >= 70000