How do I set the default tab for tab bar controller in swift

Question

I'm new to Swift, and about a 5 out of 10 on the Objective-C knowledge scale..

I created a basic three tab Swift application. Each tab has an associated swift class file, eg FirstViewController.swift , SecondViewController.swift , ThirdViewController.swift .

When I select the third tab, I now open the application preference settings using a viewDidAppear function override in ThirdViewController.swift , eg:

override func viewDidAppear(animated: Bool) {
    // open app preference s
    if let url = NSURL(string:UIApplicationOpenSettingsURLString) {
        UIApplication.sharedApplication().openURL(url)
    }
}

Though, prior to opening the preferences, I would like to set the active tab back to the first tab. How is this done elegantly in Swift.

The following does not work:

self.tabBarController.selectedIndex = 0

As the UIViewController of the ThirdViewController class does not have a tabBarController .

Brian.

Answer 1

User Omkar responded above with the correct answer. I can successfully switch the first tab using the following viewDidAppear in ThirdViewController.swft

override func viewDidAppear(animated: Bool) {         
    self.tabBarController?.selectedIndex = 0     
}

Answer 2

I followed @Paolo Sangregorio way The code to do it as follows

in appdelegate find applicationDidBecomeActive function and add this lines

let tabBarController = self.window?.rootViewController as! UITabBarController
tabBarController.selectedIndex = 0

Answer 3

//Use viewWillAppear (instead of) viewDidAppear to prevent a screen flicker


var freshLaunch = true
override func viewWillAppear(animated: Bool) {
    if freshLaunch == true {
        freshLaunch = false
        self.tabBarController.selectedIndex = 2
    }
}

Answer 4

If it is a tab bar application you should have the tabbarcontroller variable in your appdelegate. You can set the current tab by setting the selectedIndex on that variable, from the appdelegate.

Answer 5

In case you are using Tab bar item

Swift 3
@IBOutlet weak var Tabbar: UITabBar!

override func viewDidLoad() {
...
...
...
tabBar.selectedItem = tabBar.items![newIndex]

}

Answer 6

If you want him to come without delay. Yo can use in viewDidLoad()

override open func viewDidLoad() {
    super.viewDidLoad()

    // Set Default tab
    self.selectedIndex = 1
}