SWIFT（iOS）中的“无法将图像分配给* UIImageView *”错误

Question

Im trying to find the UIImageViews in the view and to assign few images to them based on the tags. But unfortunately i couldn't assign the images to UIImageView variable from an array. I couldn't really resolve the problem.

Below is the code that I wrote.

var imageViewSlot = UIImageView()
    for imageViewSlot in self.view.subviews
    {
       if (imageViewSlot .isMemberOfClass(UIImageView))
       {
            for i in 1...imagePieces.count
            {
                if (imageViewSlot.tag == i)
                {
                    imageViewSlot.image = imagePieces[i] as? UIImage //Error in this line
                }
            }
        }
    }

Any help will be appreciated. Thanks in advance.

Answer 1

• in above code var imageViewSlot = UIImageView() you gave this as global, and you used same name in for in statement that is the main problem. So because of this it donot know which type of object this is, So for that we have to mention like this (imageViewSlot as UIImageView).image = image

try below code, and check this link

 for  imageViewSlot in self.view.subviews
    {
        if (imageViewSlot .isMemberOfClass(UIImageView))
        {
            for i in 1...imagePieces.count
            {
                if (imageViewSlot.tag == i)
                {
                    var image = UIImage(named: imagePieces[i])
                    (imageViewSlot as UIImageView).image = image

                }
            }
        }
    }

Answer 2

First, you're accessing your array with an index outside its bounds. Your for loop should be from 0 up to and not including imagePieces.count .

for i in 0..<imagePieces.count
{
    if (imageViewSlot.tag == i)
    {
        imageViewSlot.image = imagePieces[i] as? UIImage //Error in this line
    }
}

Second, it looks like you're trying to find a UIImageView in your self.view.subviews , right? When you do that, you're setting imageViewSlot to a UIView . I see that you're checking if it's a member of class UIImageView , but that doesn't actually change the type of the imageViewSlot variable. You'll need to cast imageViewSlot to a UIImageView to be able to set the image property.

I'd do it like this (untested):

// Note, you don't need to declare var imageViewSlot first

for subview in self.view.subviews {
    if let imageViewSlot = subview as? UIImageView {
        for i in 0..<imagePieces.count {
            if imageViewSlot.tag == i {
                imageViewSlot.image = imagePieces[i] as UIImage
            }
        }
    }
}

If your tags are setup correctly, then you really don't need that inner for loop either. You can simplify it to something like this:

for subview in self.view.subviews {
    if let imageViewSlot = subview as? UIImageView {
        if imageViewSlot.tag >=0 && imageViewSlot < imagePieces.count {
            imageViewSlot.image = imagePieces[imageViewSlot.tag] as UIImage
        }
    }
}