Protocol Delegate Pattern with Xamarin.iOS

FinHorsley

What is the best way to replicate the Protocol Delegate pattern using .Net? I have seen examples using events, as well as examples using the native Delegates. Which is the best one to use, and if possible, could anyone drop in an example that I could have a look at?

JohnMiller

@FinHorsley,

Check out the documentation on this top and let me know if you have further questions!

FinHorsley

Cheers! Had a look through the documentation although couldn't see anything with regards to creating my own protocols/delegates. (I know they are not part of .NET, so I'm guessing im asking what the alternative is). I'm trying to set up a protocol delegate pattern between a tableview and a cell so that when a user clicks a cell, the table controller can present an alert.

krobertson

I have the same problem, the documentation only explains the C# side, and has no help for the Objective C side to connect bind to my own Objective C software. I need both sides, I can not find any help.
How to make the code below work?

// Objective C code

#import <Foundation/Foundation.h>

@class BindingTest;
@protocol BindingTestDelegate
@optional
- (void) bindingTestDidReportMessage:(BindingTest *)binder;
@end

@interface BindingTest : NSObject
{
    int      someNumber;
}
@property (nonatomic)id<BindingTestDelegate>delegateObject;

-(id)init;
- (void)testDelegate;

@end

#import "BindingTest.h"

@implementation BindingTest

-(id)init
{
    self = [super init];
    if (self)
    {
        someNumber = 0;
    }

    return self;
}

-(void)testDelegate
{
    if (nil != self.delegateObject)
    {
        [self.delegateObject bindingTestDidReportMessage:self];
    }
}

@end

// C# code

namespace client.iOS

{

   [Register("AppDelegate")]
    public partial class AppDelegate : global::Xamarin.Forms.Platform.iOS.FormsApplicationDelegate

   {

        public override bool FinishedLaunching(UIApplication app, NSDictionary options)
 
       {
 
           global::Xamarin.Forms.Forms.Init();

            LoadApplication(new App());

 

           // create the binding class and test a callback
           BindingTest bindingTest = new BindingTest();
            bindingTest.delegateObject += BindingTestDidReportMessage;
 
           bindingTest.TestDelegate();



           return base.FinishedLaunching(app, options);

       }




        public void BindingTestDidReportMessage(BindingTest binder, EventArgs args)

        {
            // I want to get here 

            int debugTest = 0;


            debugTest++;
 
           debugTest++;

            debugTest++;
 
           debugTest++;
 
       }

}
}