iOS - UITapGestureRecognizer - Selector with Arguments

Question

In my app I am dynamically adding images to my view at runtime. I can have multiple images on screen at the same time. Each image is loaded from an object. I have added a ta

Answer 1

You're almost there. UIGestureRecognizer has a view property. If you allocate and attach a gesture recognizer to each image view - just as it appears you do in the code snippet - then your gesture code (on the target) can look like this:

- (void) imageTapped:(UITapGestureRecognizer *)gr {

  UIImageView *theTappedImageView = (UIImageView *)gr.view;
}

What's less clear from the code you provided is how you associate your Plant model object with it's corresponding imageView, but it could be something like this:

NSArray *myPlants;

for (i=0; i<myPlants.count; i++) {
    Plant *myPlant = [myPlants objectAtIndex:i];
    UIImage *image = [UIImage imageNamed:myPlant.imageName];  // or however you get an image from a plant
    UIImageView *imageView = [[UIImageView alloc] initWithImage:image];  // set frame, etc.

    // important bit here...
    imageView.tag = i + 32;

    [self.view addSubview:imageView];
}

Now the gr code can do this:

- (void) imageTapped:(UITapGestureRecognizer *)gr {

  UIImageView *theTappedImageView = (UIImageView *)gr.view;
  NSInteger tag = theTappedImageView.tag;
  Plant *myPlant = [myPlants objectAtIndex:tag-32];
}