has anyone figured out how to test a view controller subclas

Question

has anyone figured out how to test a view controller subclass implemented in kotlin MPP

Kris Wong · Answer

hot damn calling `view` on the view controller will load the view and run `viewDidLoad`

Sam · Answer

Calling `view` will run through the following sequence 1 `loadViewIfNecessary ` 2 `loadView ` 3 `viewDidLoad ` The best place to customize your view controller s view hierarchy is in `loadView ` Be sure to call `super` first Any configuration of the views should happen in `viewDidLoad ` Note that your vc isn t actually attached to another view controller or window at this point so definitive size information is not available Size customizations should be done in `UIContentContainer` overrides

Sam · Answer

P S There is also a `viewIfLoaded` nullable property if you want the view but don t want to trigger loading It is available in iOS 9 0+

Kris Wong · Answer

thanks all that is working great now just trying to get an event callback to be triggered for a UISwitch it s proving much trickier

Kris Wong · Answer

wow this is frustrating normal event dispatch through UIApplication does not work from a test trying to call the selector directly using `performSelector` throws an error stating the selector is unrecognized but I know it s valid and it works fine just running the app

Sam · Answer

If you re trying to test UI behavior you need to do it within the context of a running app being driven by ui tests It s nearly impossible to synthesize touch events in iOS Have a look at this article for a start <https medium com johnsundell getting started with xcode ui testing in swift ac7b1f5101e5>

Kris Wong · Answer

will check that out i guess the question is whether it s possible in Kotlin

Sam · Answer

They can be written in ObjC so maybe <https stackoverflow com questions 40968036 ios how to implement tap on a button on xcuitest for objective c>

Kris Wong · Answer

got it so XCUIApplication is the key

Kris Wong · Answer

makes sense because the call to UIApplication for the action is where it seemed to die

Kris Wong · Answer

looks like there are no binding for the unit testing APIs

Kris Wong · Answer

I didn t even check but I bet UIApplication sharedApplication was null

Kris Wong · Answer

so what I observed is there is a UIApplication instance so a 2nd can t be created but `UIApplication sharedApplication` is null `UIApplicationMain` wasn t run and can t be run

Kris Wong · Answer

so I can dispatch to the main queue but control actions are a no op