从UITabBar初始化UIViewController的属性

Question

我需要从TabBar单击时设置ViewController的属性。

我试图做它didSelectViewController - 但ViewWillAppear完成后它被调用，一切都太迟了

我试着这样做：

- (BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController 

但viewController是发端tabBarIndex而不是目的地tabBarIndex

我该怎么办？

Answer 1

代码挖掘好以后，我发现了一种方法：

- (BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController 
{ 
    UINavigationController *nav = (UINavigationController *)viewController; 
    if ([[nav.viewControllers objectAtIndex:0] isKindOfClass:[DestinationViewController class]]) 
    { 
     DestinationViewController *vc = (DestinationViewController *)[nav.viewControllers objectAtIndex:0]; 
     vc.foo = 1; 
    } 

    return YES; 
} 

Answer 2

如果您正在使用的脚本，可以设置赛格瑞ID，然后：

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender { 
    if ([segue.identifier isEqualToString:YOUR_SEGUE_ID]) { 
     YourViewController *controller = segue.destinationViewController; 
     controller.someProperty = someProperty; 
    } 
}