Question

I’m creating a Connect Four-type game in Xcode for a class project and am getting stuck on a helper function. I have a button above each column of the “game board” to drop the piece into the game. The board is essentially a 7×6 grid of UIImageView (whether or not this is the most practical I don’t really care about, it’s about as much as we have been taught in this class).

My helper function:
(declared in .h:
NSString* imgString;
UIImageView* prevImg;
UIImageView* curImg;
)

-(void) dropToken:(int) column
{
    [ self checkTurn ];
    for(int i=1; i<6; i++)
    {
        imgString = [ NSString stringWithFormat: @"img%d%d", i, column ];
        curImg = (UIImageView*) imgString;
        curImg.image = [ UIImage imageNamed: @"redpiece.png" ];
        if(i != 6)
        {
            prevImg = curImg;
            imgString = [ NSString stringWithFormat: @"img%d%d", i+1, column ];
            curImg = (UIImageView*) imgString;
            if(curImg.image == nil)
            {
                prevImg.image = nil;
                curImg.image = curToken;
            }
        }
    }
}

it’s supposed to take in the column as a parameter, and then go to the appropriate UIImageView, and set the image there to the current players token.

However I’m getting:

-[__NSCFString setImage:]: unrecognized selector sent to instance 0x6b09ee0

on the line: curImg.image = [ UIImage imageNamed: @”redpiece.png” ];

is there an issue with my typecast? Or am I overlooking some easily fixed issue?

Answer 1

Kevin has a good point in his comment, this line will never work:

curImg = (UIImageView*) imgString;

I think you want to do something more like this:

imgString = [ NSString stringWithFormat: @"img%d%d", i, column ];
        UIImageView* imgView = [UIImageView initWithImage:[ UIImage imageNamed: @"redpiece.png" ]];

This is code I’ve written in this page, so it might not even compile but the idea is you need to create the UIImageView with a UIImage with string you created.