moving UIImageView form first tapped UIControl to second tapped UIControl - iphone

Question

I have 25 UIControls and 10 UIImageView. It looks like this:
Now the images are the UIImageVIews and the grids are the UIControls. What I want is when the user taps at a image and then taps at any of the grids (any blank grids of-course) the UIImageView is then removed from the current superView and added as the subView of the blank grid tapped. For example, if the user taps at the A1 grid first and then in the B2 grid, two actions occur,
UIImageView from A1 grid is removed,
UIImageView is added to B2 grid
This means when the user taps at the image at A1 grid and then taps at the B2 grid, the output window looks like this:
EDIT
So, at a time I need to have track for two UIControls:
1.which one is pressed first, and
2.which one is pressed second. And then remove the UIImageView from the first UIControl and add it to the second UIControl. I have tried giving the UIControls a tag like,
//....
A1.tag = 1;
//...
-(void)a1ViewTapped:(id)sender
{
int i = A1.tag;
[self switch:i];
}
//...
-(void)switch:(int)_tag
{
//....
UIView *view = (UIView*)[self.view viewWithTag:_tag];
[view removeFromSuperview];
//...
}
By this I can track a single UIControl, but need to track two of them.
How can I accomplish this, can anyone help?

Answer 1

UIControl inherits from UIView, so you can add a subview to your UIControl by calling addSubview:.
You can remove your UIImageView from the previous control by calling removeFromSuperview on the UIImageView
edit:
A very simple implementation would be to create a property that holds a reference to the selected UIControl. When the property is nil, then you are in selection mode. Touching up inside a control puts a reference to the control into the property. When the property is not nil, you are looking for a grid control in which to place the image.
You'll also need a way to keep track of whether your UIControl has one of the UIImageView instances as a subview. There are a number of ways to do that. One way would be to subclass UIControl to add a property to it that points to the UIImage it contains. Another way might be to simply examine the subviews of the UIControl to see if it contains one of the images in question. Another way would be to create some data structure to keep track of the positions of the images. How you do it is up to you, and the best way depends on the specifics of your implementation.
Just for the sake of discourse, let's assume you set up an NSMutableDictionary called imageMap that uses the tags of your UIControls as keys and sets references to the images as values. Then you could do something like:
-(void)selectGridControl:(UIView*)view
{
if (selectedControl == nil) // In this case nothing is selected
{
selectedControl = view;
}
else // In this case we are moving the image to the new view
{
UIImageView *selectedImage = [imageMap objectForKey:selectedControl.tag];
if (selectedImage != nil)
{
[selectedImage removeFromSuperview];
[view addSubview:selectedImage];
[imageMap removeObjectForKey:selectedControl.tag];
[imageMap addObject:selectedImage forKey:view.tag];
selectedControl = nil;
}
}
Initializing imageMap and handling cases when the destination control already has an image are left as exercises for the reader.