Question

This is a very elemental question about object-orientated programming- so sorry in advance if this is obvious.

I have a view and add several objects to this view (as subviews). I do this programatically. Every object get’s an individual ID so that I can later tell objects apart (in this case it is the int position). This is my code:

    for (int i=0; i < [directories count]; i++) {

    NSLog(@"%i", i);

    Notebook *aBook = [[Notebook alloc] initWithName:aName withPosition:i];
    [self.view addSubview:aBook];
    [aBook release];
    [aName release];

}

After this, a have a view with several objects attached to it. My question is how I can get to these objects now. What if I wanted to find out the name or any other variable saved in this object? E.g. how would I get the nameOfBook if I knew what the stackPosition is? Here is the header of my object notebook:

 #import <Foundation/Foundation.h>

@interface Notebook : UIView

{
    NSString *nameOfBook;
    int stackPosition;
    int bookWidth;
    int bookHeight;
    int xPosition;
    int yPosition;

}

@property (nonatomic, retain) NSString *nameOfBook;
@property int stackPosition;
@property int bookWidth, bookHeight, xPosition, yPosition;

-(id)initWithName:(NSString *)name withPosition:(int)position;
-(void)putOnScreen;

@end

Answer 1

You can create an array or dictionary of your Notebook objects and add each one into there. Then you can reference them later on by getting the array / dictionary object.

So create instance var for your array….

NSMutableArray *myBooks;

And then add your objects into the array in your loop….

[myBooks addObject:aBook];

And when you want to retrieve it later (using 0 based index)….

Notebook *theBook = [myBooks objectAtindex:myIndexNumberHere];