NSMutableArray - How to access

Question

I've a little problem: I've created two mutable arrays and added an object of "actProject" to "allProject". Everything works fine but I do not know how to display one single object of allProject (e.g. "Date").

    NSMutableArray *allProject= [[NSMutableArray alloc]initWithObjects: nil];
 NSMutableArray *actProject = [[NSMutableArray alloc]initWithObjects: nil];
 [actProject addObject:(NSString*)@"Name"];
 [actProject addObject:(NSString*)@"Description"];
 [actProject addObject:(NSString*)@"Date"];

 [allProject addObject:actProject];

 NSLog(@"test: %@",[allProject objectAtIndex:0]);

How to get "Date" only by accessing "allProject"?

Any ideas?

Solution 1

[[allProject objectAtIndex:0]objectAtIndex:2]

It's basically an array within an array, so you treat it as such.

Solution 2

Are you expecting that [allProject objectAtIndex:0] is an NSString* "Name"? Actually, it is an NSMutableArray, actProject. You're just storing an array inside of an array. This is generally not a good idea.

If you want to add the individual items of actProject to allProject, use -addObjectsFromArray.

 NSMutableArray *allProject= [NSMutableArray array];
 NSMutableArray *actProject = [NSMutableArray array];
 [actProject addObject:@"Name"];
 [actProject addObject:@"Description"];
 [actProject addObject:@"Date"];

 [allProject addObjectsFromArray:actProject];

 NSLog(@"test: %@",[allProject objectAtIndex:0]); //should be @"Name" now.

Solution 3

If I understod right you are looking for:

[[allProject objectAtIndex:0] objectAtIndex:2]

In that way in objective-C you can nest messages to objects. Btw you do not need to cast those object to (NSString *)