Added EGOUICacheCancel()

EGOUICache.h

@@ -28,6 +28,9 @@
 
 UIImage* EGOUICachedDrawing(id target, SEL selector, CGRect rect, NSString* salt);
 
+// Should be called from the method calling EGOUICachedDrawing, cancels 1 level 
+void EGOUICacheCancel();
+
 // Sets the maximum length the cache will persist for.
 // Important: This does not guarantee cache will persist for this period, since caches can be cleared at any time.
 void EGOUICacheSetCacheTimeoutInterval(NSTimeInterval cacheTimeoutInterval);

EGOUICache.m

@@ -62,20 +62,28 @@
 		[invocation setSelector:selector];
 		[invocation setArgument:&adjustedRect atIndex:2];
 		[invocation invokeWithTarget:target];
-
-		CGImageRef cgImage = CGBitmapContextCreateImage(imageContext);
-		UIGraphicsPopContext();
-		CGContextRelease(imageContext);
-
-		image = [UIImage imageWithCGImage:cgImage];
-		CGImageRelease(cgImage);
 
-		[[EGOCache currentCache] setImage:image forKey:key withTimeoutInterval:_cacheTimeoutInterval];
-
-		return image;
+		if(!_cancelCache) {
+			CGImageRef cgImage = CGBitmapContextCreateImage(imageContext);
+			UIGraphicsPopContext();
+			CGContextRelease(imageContext);
+
+			image = [UIImage imageWithCGImage:cgImage];
+			CGImageRelease(cgImage);
+
+			[[EGOCache currentCache] setImage:image forKey:key withTimeoutInterval:_cacheTimeoutInterval];
+			return image;
+		} else {
+			_cancelCache = NO;
+			return nil;
+		}
 	}
 }
 
+void EGOUICacheCancel() {
+	_cancelCache = YES;
+}
+
 void EGOUICacheSetCacheTimeoutInterval(NSTimeInterval cacheTimeoutInterval) {
 	_cacheTimeoutInterval = cacheTimeoutInterval;
 }

README.markdown

@@ -27,6 +27,9 @@ Created by enormego
 		* `EGOUICacheSetCacheTimeoutOneDay();`
 		* `EGOUICacheSetCacheTimeoutOneHour();`
 
+*	`EGOUICacheCancel();`
+	*	Cancels one level of caching.  This should be called if data hasn't yet loaded or something isn't what it's expected to be.  The image returned by `EGOUICachedDrawing()` will be nil.
+
 # Example
 
 Let's say you have a button that gets drawn a bunch of times, that uses intensive blending, and really only needs to be drawn once since the text rarely changes: