Bug 3995 - Binding NSComparator to Delegate Problem: return value not bound?
Summary: Binding NSComparator to Delegate Problem: return value not bound?
Alias: None
Product: iOS
Classification: Xamarin
Component: Tools ()
Version: 5.2
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Sebastien Pouliot
Depends on:
Reported: 2012-03-20 17:11 UTC by Marcus Wilhelm
Modified: 2012-03-21 09:51 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Marcus Wilhelm 2012-03-20 17:11:07 UTC

I try to bind the following objc method (from the Sparrow Framework):

    - (void)sortChildren:(NSComparator)comparator;

To do so, I have defined a delegate like this:

    public delegate int SPDisplayObjectComparator(SPDisplayObject obj1, SPDisplayObject obj2);

And a binding method:

    void Sort(SPDisplayObjectComparator comparator);

Example usage:

    container.Sort(delegate(SPDisplayObject o1, SPDisplayObject o2) {
        return o1.Name.CompareTo(o2.Name);

My delegate gets called fine but the sorting result is wrong, so I looked into the generated binding code and it seems that my return value is ignored and never passed to objc.

I am really new to the objc binding stuff so maybe it isn't a bug. Can you verify this? If you want to have a look into my complete binding code you can do it here: https://github.com/goosefx/sparrow-monotouch

The respective class is SPDisplayObjectContainer, a test for my binding is inside the UnitTests project Tests/SPDisplayObjectContainer 

Comment 1 Sebastien Pouliot 2012-03-20 20:42:38 UTC
You're right (good catch!). The return value form the delegate is ignored by the generated code. It seems there's only a single case where we have bindings using a non-void delegate (I'll check to see if it works / generate different code).

note: I tried this on a smaller test case, binding/testing NSArray's sortedArrayUsingComparator:
Comment 2 Sebastien Pouliot 2012-03-20 21:12:32 UTC
testing a patch...
Comment 3 Sebastien Pouliot 2012-03-21 09:47:14 UTC
Fixed in master 2454042709f9ad1da50c4b2e40c9c712ebf1cb47
and 5.2-series a63218aa067bdd7fb3f73463afbb466663b4a10f

QA: unit tests in master
Comment 4 Marcus Wilhelm 2012-03-21 09:51:33 UTC
+1 That was fast. Thanks!