Also, this code actually sets this ViewController instance as the delegate (line 13) and datasource (line 13) of the Picker View we added to the storyboard.Ĭlass ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource weak var picker: UIPickerView!Īdd the following methods to your ViewController.swift after the “didReceiveMemoryWarning” method.GEOREG BUSINESS NEWS - Swift Silliker recently hosted an information session for Southern Cape clients at its office in CJ Langenhoven Street in George. By doing this, we’re saying that the ViewController class conforms to the appropriate “rules” which allows it to be a data source for the UIPickerView class and allows it to handle events raised by the UIPickerView class. Go to ViewController.swift and make this class conform to the UIPickerViewDelegate and UIPickerViewDataSource protocols.
Now that we’ve got the UIPickerView element in our storyboard and made it accessible from code, we can add the code to connect the data to it! Now that the pickerData was initialized, we will add some data in Line 9, which is part of the viewDidLoad method. By declaring it here as an instance variable, we can access this variable from any method in this class and the variable will hold its value for the duration of the objects lifetime. In Line 3, we’re declaring a new Array instance variable to store the list of data. In ViewController.swift, add the following weak var picker: UIPickerView! Let’s create the data that we’re going display in the Picker control. You can break the connection by right-clicking the Picker View element from the storyboard and looking for the connection to the deleted property and just clicking the “x” next to that connection. Keep in mind that if you delete this IBOutlet property, you also have to break the connection from the storyboard or else your app will crash.
Run your app now to make sure it doesn’t crash. Now we can reference that Picker View element from code in the ViewController using “self.picker”. Do any additional setup after loading the view, typically from a nib. Just name it “picker”.Īfter doing that, your ViewController.swift file will look like this:Ĭlass ViewController: UIViewController weak var picker: UIPickerView! Drop it in between the class ViewController and override func viewDidLoad.Ī small dialog will pop up to ask you for a name for this IBOutlet property. Then hold down control and click the UIPickerView element in the storyboard and drag your mouse over to the right side. Now that we’ve got the Picker View element on the view in the storyboard, we’ll need to expose this element to be accessible via code in the ViewController.Ĭlick the Assistant Editor button and make sure that the storyboard is in the left pane and that ViewController.swift is in the right. Once you’ve found it, drag it onto your view.
The list of elements will filter down to the UIPickerView element. Make sure you’ve selected the Objects library tab and type in “pickerview”. If you don’t see this right hand pane, click on the icon in the upper right corner to toggle the pane. On the right hand side, you’ve got your Attribute Inspector View (top half) and your Library View (bottom half). Adding and Connecting the UIPickerViewįrom the file navigator on the left, select Main.storyboard and the editor will change to a design view where you can see what your view will look like. To accomplish this, go to the newly created Main.storyboard file and disable Use Auto Layout and select iPhoneĢ. Since this article is not covering size classes and auto-layout, we want to make sure that our UIPickerView is well positioned in the Simulator. We’ll start with creating an Xcode single view application project to demonstrate the UIPickerView.įor the project settings, you can enter any sort of details since this will just be for demo purposes. In this tutorial, we’ll walk though a basic implementation example of the UIPickerView which is a UI element that can be used to make a selection from multiple choices (similar to what a dropdown does for a webpage). Oct 14, 2018: Updated by Adrien Villez for the latest Xcode 10!
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