阻止tabbar更改特定索引处的选项卡 - IOS [英] Prevent tabbar from changing tab at specific index - IOS

问题描述

感谢您阅读我的问题。

当用户点击索引为4的标签时，我正在尝试实现弹出菜单。所以我正在尝试防止tabbar在按下索引4时切换viewcontroller。

I'm trying to implement a popup menu when a user clicks the tab with the index of 4. So I'm trying to prevent the tabbar from switching viewcontroller when index 4 is pressed.

这是我的代码：

- (BOOL) tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController
{
    if(viewController == [tabBarController.viewControllers objectAtIndex:4]){        
        NSLog(@"NO");
        return NO;
    }else{
        NSLog(@"YES");
        return YES;
    }

}

我已实施 UITabBarControllerDelegate 和 self.delegate = self; 在 viewDidLoad 中只工作一次。

I've implemented the UITabBarControllerDelegate and self.delegate = self; in the viewDidLoad and it works but just one time.

单击索引4选项卡时，菜单显示且标签栏未切换视图（ GREAT ），但是当我再次单击它时即使我得到LogNO，视图也会改变。
这可能是什么问题？

When I click the index 4 tab the menu shows and the tabbar doesn't switch view (GREAT), but when I click it again the view changes even if I get the Log "NO". What could be the problem here?

感谢您的任何建议！

已解决

感谢Kasaname在下面的回答，我通过添加selectedindex并将其设置为标志索引（prevtab）来解决它。我将prevtab更改为上次选择的选项卡的索引，当用户选择索引4时将其更改。
我的最终代码：

Thanks to Kasaname's answer below I solved it by adding selectedindex and set it to a flag index (prevtab). I change the prevtab to the index of the last selected tab, exept for when the user selects index 4. My final code:

- (BOOL) tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController
{
    if(viewController == [tabBarController.viewControllers objectAtIndex:4]){
        self.selectedIndex = prevTab; //only change in this method       
        return NO;
    }else{        
        return YES;
    }

}

推荐答案

- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController {
    if (tabBarController.selectedIndex == 0) {

    } else if (tabBarController.selectedIndex == 1) {

    } else if (tabBarController.selectedIndex == 2) {

    }
}

为什么不使用此委托
使用此委托它将起作用我猜想

why dont u use this delegate Use this delegate it will work i suppose

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