Moving UIImageViews in ScrollView - objective-c

Question

In my scrollview im having multiple imageviews where i can able to move each imageviews when user taps LONGPRESS i have done this using,
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(moveImage:)];
[panGesture setMaximumNumberOfTouches:2];
[panGesture setDelegate:self];
[imageview addGestureRecognizer:panGesture];
UILongPressGestureRecognizer *longPressRecognizer = [[UILongPressGestureRecognizer alloc] init];
[imageview addGestureRecognizer:longPressRecognizer];
- (BOOL) gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
return YES;
}
- (void)adjustAnchorPointForGestureRecognizer:(UIGestureRecognizer *)gestureRecognizerv {
if (gestureRecognizer.state == UIGestureRecognizerStateBegan) {
UIView *piece = gestureRecognizerv.view;
CGPoint locationInView = [gestureRecognizerv locationInView:piece];
CGPoint locationInSuperview = [gestureRecognizerv locationInView:piece.superview];
piece.layer.anchorPoint = CGPointMake(locationInView.x / piece.bounds.size.width, locationInView.y / piece.bounds.size.height);
piece.center = locationInSuperview;
}
}
- (void)moveImage:(UIPanGestureRecognizer *)gestureRecognizerg
{
NSLog(#"sdfgdsgsdg");
UIView *piece = [gestureRecognizerg view];
[self adjustAnchorPointForGestureRecognizer:gestureRecognizerg];
// need to test if the scrollview is already using the touches. If it is, leave them
if (!galleryView.tracking) {
if ([gestureRecognizerg state] == UIGestureRecognizerStateBegan || [gestureRecognizerg state] == UIGestureRecognizerStateChanged) {
CGPoint translation = [gestureRecognizerg translationInView:[piece superview]];
[piece setCenter:CGPointMake([piece center].x + translation.x, [piece center].y + translation.y)];
[gestureRecognizerg setTranslation:CGPointZero inView:[piece superview]];
}
}
}
Here my problem is the THE IMAGEVIEW is moving every where in scollview i need to rearrange the views i.e like Gallery view.

Answer 1

To get that rearrangement behavior you're going to need to have some logic that sets up a grid and 'snaps' elements to it, moves elements out the way when required, etc. It is reasonably complicated. Your current code simply moves views with your gestures.
However, if you are able to target iOS 6 and above you will almost certainly want to use a UICollectionView instead, which gives you a lot of this for free. Collection views simplify the layout and logic behind re-arranging, and will generally make your life a lot easier.