Re: adding a delegate to a class
Re: adding a delegate to a class
- Subject: Re: adding a delegate to a class
- From: "Jesse Armand" <email@hidden>
- Date: Tue, 10 Jun 2008 20:52:00 +0700
Hello Angelo,
I think this code might help you:
@protocol BackgroundObjDelegate <NSObject>
@optional
- (void)showText:(NSString*)text;
@end
@interface BackgroundObj : NSObject
{
id<BackgroundObjDelegate> _delegate;
}
@property(assign) id<BackgroundObjDelegate> delegate
- (void) sayHi;
@end
@implementation BackgroundObj
@synthesize delegate=_delegate;
- (void) sayHi
{
if ([_delegate respondsToSelector:@selector(showText:)])
[_delegate showText:@"Hi"];
}
@end
Then, you could implement your delegate class, for example:
@interface ForegroundObj : NSObject <BackgroundObjDelegate>
{
// Insert your instance variables
}
- (void)showText:(NSString*)text;
@end
@implementation ForegroundObj
- (id)init
{
if (![super init])
return nil;
BackgroundObj *obj = [[BackgroundObj alloc] init];
obj.delegate = self; // set the background object delegate
return self;
}
- (void)showText:(NSString*)text
{
// Insert your code
}
@end
If you have any questions, just ask, and please read Apple Docs, since
it's already quite complete in explaining these.
Regards,
Jesse
-------------------------------------------------------------------------------------------------
barablu (www.barablu.com), iPhone developer (http://jessearm.blogspot.com)
2008/6/10 Angelo Chen <email@hidden>:
> Hi,
>
> I have a code like this:
>
> @interface BackgroundObj : NSObject
> {
> Controller *mc;
> }
>
> - (void) sayHi;
>
>
> @implementation BackgroundObj
>
> - (void) sayHi
> {
> [mc showText:@"Hi"];
> }
> @end
>
> As you can see, the code is hard coded to use class Controller, can not be used with any other object, I'd like to add a delegate which will have a showText method, sayHi method will just call the delegate instead of hard coded Controller, any idea how to add delegates to this object? or, any tutorials for this? Thanks,
>
> Angelo
>
>
>
>
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