Added Tint Color Support

GIKPopoverBackgroundView-Example/GIKViewController.m

@@ -36,7 +36,8 @@ - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
     {
         segueIdentifier = segue.identifier;
         popoverController = [(UIStoryboardPopoverSegue *)segue popoverController];
-        popoverController.popoverBackgroundViewClass = [GIKPopoverBackgroundView class];
+//        popoverController.popoverBackgroundViewClass = [GIKPopoverBackgroundView class];
+        popoverController.popoverBackgroundViewClass = [GIKPopoverBackgroundView classWithTintColor:[UIColor redColor]];
 
         if ([segue.identifier isEqualToString:@"popover2"])
         {
@@ -49,9 +50,9 @@ - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
 - (void)applyTitleTextAttributesToNavigationBar:(UINavigationBar *)navBar
 {
     NSDictionary *attributes = @{ UITextAttributeTextColor : [UIColor colorWithRed:122.0/255.0 green:120.0/255.0 blue:114.0/255.0 alpha:1.0],
-                                  UITextAttributeTextShadowColor : [UIColor whiteColor],
-                                  UITextAttributeTextShadowOffset : [NSValue valueWithCGSize:(CGSize){ .width = 0.0, .height = 1.0}] };
-
+    UITextAttributeTextShadowColor : [UIColor whiteColor],
+    UITextAttributeTextShadowOffset : [NSValue valueWithCGSize:(CGSize){ .width = 0.0, .height = 1.0}] };
+    
     [navBar setTitleTextAttributes:attributes];
 }
 

GIKPopoverBackgroundView/GIKPopoverBackgroundView.h

@@ -12,7 +12,7 @@
 // Layout of images will be handled automatically, and it works with all values of UIPopoverArrowDirection.
 
 #import <UIKit/UIKit.h>
-
+#import <QuartzCore/QuartzCore.h>
 /**
  Image-specific values for calulating the background's layout.
  */
@@ -60,6 +60,7 @@ static const CGFloat kSecondHalfRightInset          = 9.0; // Value for .right i
 @property (nonatomic, assign) CGFloat arrowOffset;
 @property (nonatomic, assign) UIPopoverArrowDirection arrowDirection;
 
++ (id)classWithTintColor:(UIColor*)color;
 + (CGFloat)arrowHeight;
 + (CGFloat)arrowBase;
 + (UIEdgeInsets)contentViewInsets;

GIKPopoverBackgroundView/GIKPopoverBackgroundView.m

@@ -6,7 +6,6 @@
 //
 
 #import "GIKPopoverBackgroundView.h"
-#import <QuartzCore/QuartzCore.h>
 
 // A struct containing the min and max horizontal and vertical positions for the popover arrow. If the arrow's position exceeds these limits, the PopoverBackgroundArrow[UpRight|DownRight|SideTop|SideBottom].png images are drawn.
 struct GIKPopoverExtents {
@@ -27,6 +26,7 @@ @interface GIKPopoverBackgroundView () {
 
 @end
 
+static UIColor *tintColor = nil;
 
 @implementation GIKPopoverBackgroundView
 
@@ -36,6 +36,15 @@ @implementation GIKPopoverBackgroundView
 
 #pragma mark - UIPopoverBackgroundView required values
 
++ (id)classWithTintColor:(UIColor*)color
+{
+    Class class = [super class];
+    if (class) {
+        tintColor = color;
+    }
+    return class;
+}
+
 + (UIEdgeInsets)contentViewInsets
 {
     return kPopoverEdgeInsets;
@@ -119,7 +128,7 @@ - (void)addDropShadowIfNecessary
 - (void)layoutSubviews
 {
     [super layoutSubviews];
-        
+
     _popoverExtents = (GIKPopoverExtents){
         .left   = CGRectGetMinX(self.bounds) + kPopoverCornerRadius,
         .right  = CGRectGetMaxX(self.bounds) - kPopoverCornerRadius,
@@ -134,7 +143,7 @@ - (void)layoutSubviews
     self.popoverBackground.center = self.center;
     self.popoverBackground.bounds = self.bounds;
 
-    self.popoverBackground.image = [self wantsUpOrDownArrow] ? [self upOrDownArrowImage] : [self sideArrowImage];    
+    self.popoverBackground.image = [self wantsUpOrDownArrow] ? [self upOrDownArrowImage] : [self sideArrowImage];
 }
 
 
@@ -220,7 +229,7 @@ - (BOOL)isArrowAtBottomEdgeOfPopover { return (_arrowCenter + _halfBase > _popov
 
 - (void)adjustCentersIfNecessary
 {
-     // fix centers of left-pointing popovers so that their shadows are drawn correctly.   
+    // fix centers of left-pointing popovers so that their shadows are drawn correctly.
     if (self.arrowDirection == UIPopoverArrowDirectionLeft)
     {
         self.center = (CGPoint){ .x = self.center.x + [GIKPopoverBackgroundView arrowHeight], .y = self.center.y };
@@ -233,13 +242,13 @@ - (void)adjustCentersIfNecessary
 
 - (UIImage *)stretchableImageNamed:(NSString *)name insets:(UIEdgeInsets)insets mirrored:(BOOL)mirrored
 {
-    UIImage *image = [UIImage imageNamed:name];
+        UIImage *image = (tintColor) ? [self tintedImage:[UIImage imageNamed:name] usingColor:tintColor] : [UIImage imageNamed:name];
     return (mirrored) ? [[self mirroredImage:image] resizableImageWithCapInsets:[self mirroredInsets:insets]] : [image resizableImageWithCapInsets:insets];
 }
 
 - (UIImage *)twoPartStretchableImageNamed:(NSString *)name insets:(UIEdgeInsets)insets
 {
-    UIImage *image = [UIImage imageNamed:name];
+    UIImage *image = (tintColor) ? [self tintedImage:[UIImage imageNamed:name] usingColor:tintColor] : [UIImage imageNamed:name];
 
     if (self.arrowDirection == UIPopoverArrowDirectionLeft)
     {
@@ -300,4 +309,31 @@ - (UIImage *)imageFromImageContextWithSourceImage:(UIImage *)image size:(CGSize)
     return result;
 }
 
+- (UIImage *)tintedImage:(UIImage*)image usingColor:(UIColor *)tintColor;
+{
+    UIGraphicsBeginImageContextWithOptions(image.size, NO, 1.0);
+    CGContextRef context = UIGraphicsGetCurrentContext();
+    CGRect rect = CGRectMake(0, 0, image.size.width, image.size.height);
+
+    // draw original image
+    [image drawInRect:rect blendMode:kCGBlendModeNormal alpha:1.0f];
+
+    // tint image (loosing alpha).
+    // kCGBlendModeOverlay is the closest I was able to match the
+    // actual process used by apple in navigation bar
+    // kCGBlendModeMultiply is used currently because it provides
+    // the best replacement of image. The overlay mode will create
+    // just that an overlay, the color will seem washed out.
+    CGContextSetBlendMode(context, kCGBlendModeMultiply);
+    [tintColor setFill];
+    CGContextFillRect(context, rect);
+
+    // mask by alpha values of original image
+    [image drawInRect:rect blendMode:kCGBlendModeDestinationIn alpha:1.0f];
+
+    UIImage *tintedImage = UIGraphicsGetImageFromCurrentImageContext();
+    UIGraphicsEndImageContext();
+    return tintedImage;
+}
+
 @end

README.md

@@ -75,6 +75,40 @@ The documentation for `UIPopoverBackgroundView` states that `-setArrowOffset:` i
 }
 ```
 
+### Tint support
+
+PopoverControls have historically never supported tinting of the view. This fork contains the ability to use the tint function added.
+
+Tinting was achieved by adding a method to modify the images that are included on the fly.
+
+``` objective-c
+- (UIImage *)tintedImage:(UIImage*)image usingColor:(UIColor *)tintColor;
+{
+    UIGraphicsBeginImageContextWithOptions(image.size, NO, 1.0);
+    CGContextRef context = UIGraphicsGetCurrentContext();
+    CGRect rect = CGRectMake(0, 0, image.size.width, image.size.height);
+
+    // draw original image
+    [image drawInRect:rect blendMode:kCGBlendModeNormal alpha:1.0f];
+
+    // tint image (loosing alpha).
+    // kCGBlendModeOverlay is the closest I was able to match the
+    // actual process used by apple in navigation bar
+    CGContextSetBlendMode(context, kCGBlendModeMultiply);
+    [tintColor setFill];
+    CGContextFillRect(context, rect);
+
+    // mask by alpha values of original image
+    [image drawInRect:rect blendMode:kCGBlendModeDestinationIn alpha:1.0f];
+
+    UIImage *tintedImage = UIGraphicsGetImageFromCurrentImageContext();
+    UIGraphicsEndImageContext();
+    return tintedImage;
+}
+```
+
+From the method above we can see that we are modifying the image by setting the blend mode of the image to multiply for a better color replacement. Overlay mode is included but commented out because it creates a more washed out image.
+
 ## Usage
 
 To use, add GIKPopoverBackgroundView.h and GIKPopoverBackgroundView.m to your Xcode project. Feel free to use the supplied images (found in the example project) and their default `UIEdgeInsets` values. In the view controller which manages your popover controller, set the popover controller's `popoverBackgroundViewClass` property:
@@ -84,9 +118,23 @@ popoverController = [(UIStoryboardPopoverSegue *)segue popoverController];
 popoverController.popoverBackgroundViewClass = [GIKPopoverBackgroundView class];
 ```
 
+to use the tint option, add GIKPopoverBackgroundView.h and .m as you would before.
+
+``` objective-c
+popoverController = [(UIStoryboardPopoverSegue *)segue popoverController];
+popoverController.popoverBackgroundViewClass = [GIKPopoverBackgroundView classWithTintColor:(UIColor*)];
+```
+
 ## Sample Project
 
 The included sample project covers a number of scenarios where source images are stretched twice, mirrored, and animated in response to keyboard appearance.
+The original images can be seen by uncommenting the line in the GIKViewController.m
+
+```objective-c
+popoverController.popoverBackgroundViewClass = [GIKPopoverBackgroundView class];
+```
+
+
 
 ## Requirements
 
@@ -101,12 +149,18 @@ GIKPopoverBackgroundView uses ARC and requires iOS 5.0 or above.
 
 GIKPopoverBackgroundView was created by [Gordon Hughes](https://github.com/gik/).
 
+Tint Support Added By [Eric Rolf](https://github.com/xrolfex/).
+
 ## Contact
 
 [Gordon Hughes](https://github.com/gik/)
 
 [@gordonhughes](http://twitter.com/gordonhughes)
 
+[Eric Rolf](https://github.com/xrolfex/)
+
+[@Eric_Rolf](https://twitter.com/eric_rolf)
+
 ## License
 
 GIKPopoverBackgroundView is available under the MIT license. See the LICENSE file for more information.