Creating an abstract class in Objective-C

Question

I\'m originally a Java programmer who now works with Objective-C. I\'d like to create an abstract class, but that doesn\'t appear to be possible in Objective-C. Is this poss

Answer 1

A simple example of creating an abstract class

// Declare a protocol
@protocol AbcProtocol 

-(void)fnOne;
-(void)fnTwo;

@optional

-(void)fnThree;

@end

// Abstract class
@interface AbstractAbc : NSObject

@end

@implementation AbstractAbc

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

-(void)fnOne{
// Code
}

-(void)fnTwo{
// Code
}

@end

// Implementation class
@interface ImpAbc : AbstractAbc

@end

@implementation ImpAbc

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

// You may override it    
-(void)fnOne{
// Code
}
// You may override it
-(void)fnTwo{
// Code
}

-(void)fnThree{
// Code
}

@end