Contents

WKInterfaceObject

An object that provides information that is common to all interface objects in your watchOS app.

Declaration

class WKInterfaceObject

Mentioned in

Overview

Your WatchKit extension uses interface objects to manipulate the visual elements displayed on Apple Watch. Specifically, you use the methods of this class to change the size, alignment, and visibility of those elements. You can also configure the accessibility information displayed through assistive technologies like VoiceOver.

Do not subclass or create instances of this class, or any of its subclasses, yourself. Instead, define outlets in your interface controller class and connect them to the corresponding objects in your storyboard file. For example, to refer to a button in your interface, define a property with the following syntax in your interface controller class:

At runtime, WatchKit creates the appropriate interface objects and assigns them to the outlets in your interface controller.

WatchKit provides one-way communication between the interface objects in your extension and the corresponding interface elements in your watchOS app. You can set the values of an interface object, but you cannot get the current values. If you want to know the current value of an attribute, you must save the value yourself.

Interface Builder Configuration Options

Xcode lets you configure information about your group interface object in your storyboard file. The following table lists the attributes you can configure in your storyboard and their meaning.

Attribute

Description

Alpha

The opacity of the object. A value of 1.0 represents fully opaque and a value of 0.0 represents fully transparent.

Hidden

A checkbox indicating whether the item is hidden initially. You can change the visibility of the item programmatically by calling the Sethidden(_:) method.

Installed

A checkbox indicating whether the item is installed for the current device.

Horizontal

The horizontal alignment of the item. Use this attribute to configure the horizontal position of the item relative to its immediate parent.

Vertical

The vertical alignment of the item. Use this attribute to configure the vertical position of the item relative to its immediate parent.

Width

The width of the object. Specify a fixed width or set the value of the object to be a percentage of its container’s width.

Height

The height of the object. Specify a fixed height or set the value of the object to be a percentage of its container’s height.

Topics

Hiding and Showing an Object

Getting the Property Name

Changing an Object’s Size

Setting an Object’s Alignment

Configuring the Accessibility Attributes

Setting the Layout Direction

Constants

See Also

User interface basics