From 4a7d644547cb783c39315bb12761092f23493067 Mon Sep 17 00:00:00 2001
From: BJ Homer <bjhomer@BJs-MacBook.local>
Date: Sat, 20 Nov 2010 17:18:27 -0700
Subject: [PATCH] Shift other images on the fly while we're dragging.

---
 Classes/HSSidebarView.m         | 53 +++++++++++++++++++++++++--------
 Classes/HSSidebarViewDelegate.h |  1 +
 Classes/SidebarViewController.m |  4 +++
 3 files changed, 46 insertions(+), 12 deletions(-)

diff --git a/Classes/HSSidebarView.m b/Classes/HSSidebarView.m
index d7b2ce7..6a42e11 100644
--- a/Classes/HSSidebarView.m
+++ b/Classes/HSSidebarView.m
@@ -17,7 +17,10 @@ @interface HSSidebarView ()
 
 @property (retain) NSMutableArray *imageViews;
 @property (assign) BOOL initialized;
+
 @property (retain) UIView *viewBeingDragged;
+@property (assign) NSInteger draggedViewOldIndex;
+@property (assign) CGFloat dragOffsetY;
 
 // readwrite overrides of public readonly methods
 @property (readwrite) NSUInteger imageCount;
@@ -36,6 +39,8 @@ @implementation HSSidebarView
 @synthesize selectionGradient;
 @synthesize initialized;
 @synthesize viewBeingDragged;
+@synthesize draggedViewOldIndex;
+@synthesize dragOffsetY;
 @synthesize selectedIndex;
 @synthesize imageCount;
 @synthesize delegate;
@@ -109,13 +114,17 @@ - (void)layoutSubviews {
 		self.initialized = YES;
 	}
 	else {
-		[UIView animateWithDuration:0.1
-						 animations:
-		 ^{
-			 [imageViews enumerateObjectsUsingBlock:^(UIView *view, NSUInteger idx, BOOL *stop) {
-				 view.center = [self imageViewCenterInScrollViewForIndex:idx];
-			 }];
-		 }];
+		[UIView animateWithDuration:0.2
+							  delay:0
+							options:UIViewAnimationOptionAllowUserInteraction
+						 animations:^{
+							 [imageViews enumerateObjectsUsingBlock:^(UIView *view, NSUInteger idx, BOOL *stop) {
+								 if (view != self.viewBeingDragged) {
+									 view.center = [self imageViewCenterInScrollViewForIndex:idx];
+								 }
+							 }];
+						 }
+						completion:NULL];
 	}
 	
 	// Draw selection layer
@@ -172,25 +181,45 @@ - (void)pressedSidebar:(UILongPressGestureRecognizer *)recognizer {
 	
 	if (recognizer.state == UIGestureRecognizerStateBegan) {
 		self.selectedIndex = -1;
-		hitView.alpha = 0.5;
+		[UIView animateWithDuration:0.1
+						 animations:^{
+							 hitView.alpha = 0.5;
+							 hitView.transform = CGAffineTransformMakeScale(1.1, 1.1);
+						 }
+		 ];
 		self.viewBeingDragged = hitView;
+		self.draggedViewOldIndex = currentIndex;
+		self.dragOffsetY = hitY - [self imageViewCenterInScrollViewForIndex:currentIndex].y;
 		[_scrollView bringSubviewToFront:viewBeingDragged];
 	}
 	else if (recognizer.state == UIGestureRecognizerStateChanged) {
 		CGPoint newPosition = [recognizer locationInView:_scrollView]; 
-		viewBeingDragged.center = CGPointMake(viewBeingDragged.center.x, newPosition.y);
+		viewBeingDragged.center = CGPointMake(viewBeingDragged.center.x, newPosition.y - self.dragOffsetY);
+		[imageViews removeObject:viewBeingDragged];
+		[imageViews insertObject:viewBeingDragged atIndex:currentIndex];
+		[self setNeedsLayout];
 	}
 	else {
 		CGPoint finalPosition = [self imageViewCenterInScrollViewForIndex:currentIndex];
-		[UIView animateWithDuration:0.1
+		[UIView animateWithDuration:0.2
 						 animations:^{
 							 viewBeingDragged.center = finalPosition;
 							 viewBeingDragged.alpha = 1.0;
+							 viewBeingDragged.transform = CGAffineTransformIdentity;
+						 }
+						 completion:^(BOOL finished){
+							 self.selectedIndex = currentIndex;
+							 [self setNeedsLayout];
 						 }];
 		[imageViews removeObject:viewBeingDragged];
 		[imageViews insertObject:viewBeingDragged atIndex:currentIndex];
-		self.selectedIndex = currentIndex;
-		[self setNeedsLayout];
+		
+		if ([delegate respondsToSelector:@selector(sidebar:didMoveImageAtIndex:toIndex:)]) {
+			[delegate sidebar:self didMoveImageAtIndex:self.draggedViewOldIndex toIndex:currentIndex];
+		}
+		
+		self.draggedViewOldIndex = -1;
+		self.dragOffsetY = 0;
 		self.viewBeingDragged = nil;
 	}
 }
diff --git a/Classes/HSSidebarViewDelegate.h b/Classes/HSSidebarViewDelegate.h
index 6811d4d..d04b3bc 100644
--- a/Classes/HSSidebarViewDelegate.h
+++ b/Classes/HSSidebarViewDelegate.h
@@ -15,6 +15,7 @@
 #pragma mark Delegate methods
 @optional
 - (void)sidebar:(HSSidebarView *)sidebar didTapImageAtIndex:(NSUInteger)anIndex;
+- (void)sidebar:(HSSidebarView *)sidebar didMoveImageAtIndex:(NSUInteger)oldIndex toIndex:(NSUInteger)newIndex;
 
 #pragma mark -
 #pragma mark Data source methods
diff --git a/Classes/SidebarViewController.m b/Classes/SidebarViewController.m
index 3fbb611..51c5088 100644
--- a/Classes/SidebarViewController.m
+++ b/Classes/SidebarViewController.m
@@ -69,6 +69,10 @@ -(void)sidebar:(HSSidebarView *)sidebar didTapImageAtIndex:(NSUInteger)anIndex {
 	NSLog(@"Touched selected image at index: %u", anIndex);
 }
 
+- (void)sidebar:(HSSidebarView *)sidebar didMoveImageAtIndex:(NSUInteger)oldIndex toIndex:(NSUInteger)newIndex {
+	NSLog(@"Image at index %d moved to index %d", oldIndex, newIndex);
+}
+
 - (void)dealloc {
     [_sidebar release];
     [super dealloc];