Added support to extend the backgroundView up or down independently to make it visible through a UIScrollView bounce.

Author: Zac White

Classes/AQGridView.h

@@ -128,6 +128,8 @@ extern NSString * const AQGridViewSelectionDidChangeNotification;
 		unsigned	numColumns:6;
 		unsigned	separatorStyle:3;
 		unsigned	allowsSelection:1;
+		unsigned	backgroundViewExtendsUp:1;
+		unsigned	backgroundViewExtendsDown:1;
 		unsigned	usesPagedHorizontalScrolling:1;
 		unsigned	updating:1;				// unused
 		unsigned	ignoreTouchSelect:1;
@@ -213,6 +215,8 @@ extern NSString * const AQGridViewSelectionDidChangeNotification;
 @property (nonatomic, assign) BOOL clipsContentWidthToBounds __attribute__((deprecated));	// default is YES. If you want to enable horizontal scrolling, set this to NO.
 
 @property (nonatomic, retain) UIView * backgroundView;		// specifies a view to place behind the cells
+@property (nonatomic) BOOL backgroundViewExtendsUp;			// default is NO. If YES, the background view extends upward and is visible during a bounce.
+@property (nonatomic) BOOL backgroundViewExtendsDown;		// default is NO. If YES, the background view extends downward and is visible during a bounce.
 @property (nonatomic) BOOL usesPagedHorizontalScrolling;	// default is NO, and scrolls verticalls only. Set to YES to have horizontal-only scrolling by page.
 
 @property (nonatomic) AQGridViewCellSeparatorStyle separatorStyle;	// default is AQGridViewCellSeparatorStyleEmptySpace

Classes/AQGridView.m

@@ -220,6 +220,26 @@ - (void) setAllowsSelection: (BOOL) value
 	_flags.allowsSelection = (value ? 1 : 0);
 }
 
+- (BOOL) backgroundViewExtendsDown
+{
+	return ( _flags.backgroundViewExtendsDown);
+}
+
+- (void) setBackgroundViewExtendsDown: (BOOL) value
+{
+	_flags.backgroundViewExtendsDown = (value ? 1 : 0);
+}
+
+- (BOOL) backgroundViewExtendsUp
+{
+	return ( _flags.backgroundViewExtendsUp);
+}
+
+- (void) setBackgroundViewExtendsUp: (BOOL) value
+{
+	_flags.backgroundViewExtendsUp = (value ? 1 : 0);
+}
+
 - (BOOL) requiresSelection
 {
 	return ( _flags.requiresSelection );
@@ -596,6 +616,8 @@ - (void) reloadData
 	_flags.allCellsNeedLayout = 1;
 }
 
+#define MAX_BOUNCE_DISTANCE (500.0f)
+
 - (void) layoutSubviews
 {
 	if ( (_flags.needsReload == 1) && (_animationCount == 0) && (_reloadingSuspendedCount == 0) )
@@ -619,7 +641,18 @@ - (void) layoutSubviews
 	rect.size.width = self.bounds.size.width;
 	rect.size.height = self.contentSize.height -  (_gridData.topPadding + _gridData.bottomPadding);
 	rect.origin.y += _gridData.topPadding;
-	self.backgroundView.frame = rect;
+	
+	CGRect backgroundRect = CGRectMake(rect.origin.x, rect.origin.y, rect.size.width, rect.size.height);
+	
+	if ([self backgroundViewExtendsUp]) {
+		backgroundRect.origin.y = backgroundRect.origin.y - MAX_BOUNCE_DISTANCE;
+	}
+	
+	if ([self backgroundViewExtendsDown]) {
+		backgroundRect.size.height = backgroundRect.size.height + MAX_BOUNCE_DISTANCE;
+	}
+	
+	self.backgroundView.frame = backgroundRect;
 
 	if ( _headerView != nil )
 	{
@@ -1091,7 +1124,18 @@ - (void) setBackgroundView: (UIView *) newView
 	_backgroundView.autoresizingMask = UIViewAutoresizingFlexibleWidth|UIViewAutoresizingFlexibleHeight;
 	CGRect frame = self.bounds;
 	frame.size = self.contentSize;
-	_backgroundView.frame = self.bounds;//UIEdgeInsetsInsetRect( frame, self.contentInset );
+	
+	CGRect backgroundRect = CGRectMake(0.0f, 0.0f, self.bounds.size.width, self.bounds.size.height);
+	
+	if ([self backgroundViewExtendsUp]) {
+		backgroundRect.origin.y = backgroundRect.origin.y - MAX_BOUNCE_DISTANCE;
+	}
+	
+	if ([self backgroundViewExtendsDown]) {
+		backgroundRect.size.height = backgroundRect.size.height + MAX_BOUNCE_DISTANCE;
+	}
+	
+	_backgroundView.frame = backgroundRect;
 
 	[self insertSubview: _backgroundView atIndex: 0];