Creating iOS UI components from NUnit test code

Question

I'm trying to write a unit test for some code that programmatically creates UIButtons, but when I call this code from the test, I get a NullReferenceException. Stepping through in the debugger, it looks like UIButton.FromType() returns null.

Here's the method I'm testing:

    public UIButton makeButton (String title, Action<IWelcomeController> action)
    {
        UIButton button = UIButton.FromType (UIButtonType.RoundedRect);
        // button is null here
        button.SetTitle(title, UIControlState.Normal);
        button.TouchUpInside += (sender, e) => {
            action(controller);
        };
        return button;
    }

And here's the test method:

    [Test()]
    public void TestMakeButtonTitle ()
    {
        String title = "Elvis";
        UIButton button = GetFactory().makeButton(title, delegate(IWelcomeController w) {});
        Assert.AreEqual(title, button.Title(UIControlState.Normal));
    }

I'm guessing there's some magic I need to do environment-wise in order to get MonoTouch.UIKit to work outside of a real application. Any hints? (And if it isn't possible, suggested alternative approaches?)

score 1 · Accepted Answer · answered Dec 10 '10 at 20:31

Pretty sure at this point that the fundamental problem is, if you're not running on the iPhone or in the iPhone simulator, there's no way to call the necessary native APIs to instantiate the components.

Maybe someday someone will compile NUnit for Monotouch and write an iOS test runner...

score 0 · Answer 2 · answered Oct 14 '10 at 08:48

0

I'm going to assume you've added the NUnit project to your monotouch solution and had it reference the monotouch project(s).

It seems it doesn't know where the Monotouch .dlls are so add them as a reference to your NUnit. These can be found at:

~/Developer/Monotouch/usr/lib/mono/<version>

That should solve your problem.

answered Oct 14 '10 at 08:48

Luke

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If that were the case, I would expect the code not to compile, or to blow up when I try to load the UIButton class, or call FromType(). I wouldn't expect the FromType() call to succeed but return null. – David Moles Oct 26 '10 at 21:07

score 0 · Answer 3 · edited May 23 '17 at 12:31

0

Maybe someday someone will compile NUnit for Monotouch and write an iOS test runner...

Such a runner for iOS now exists and it even ships with the latest MonoTouch 5.1.x (beta) releases.

edited May 23 '17 at 12:31

Community

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answered Jan 20 '12 at 03:19

poupou

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Creating iOS UI components from NUnit test code

3 Answers3

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