core-graphics

I draw a line using CGContextAddLineToPoint in my app now i want to remove line from given points how can i do this i am using touches for drawing line You can erase, Given the two points, draw the line with same attributes(lineWidth etc.,) by setting the CGContextSetBlendMode(context, kCGBlendModeClear) . 来源： https://stackoverflow.com/questions/10601691/how-to-remove-line-in-core-graphics

I'm trying to take an image that I have in a image object and render into a Core Graphics PDF context-- happens to be on an iPhone but this question surely applies equally to desktop Quartz. This UIImage is a simple color-on-white image at about 600x800 resolution. If I (say) turn it into a PNG file, that file looks exactly as expected-- so the data is OK. Here's what I'm doing to generate the PDF: NSMutableData * outputData = [[NSMutableData alloc] init]; CGDataConsumerRef dataConsumer = CGDataConsumerCreateWithCFData((CFMutableDataRef)outputData); CFMutableDictionaryRef attrDictionary = NULL

I need to make a progress circle like this: I have created a CAShapeLayer for the circle, and animate its strokeEnd property like this: pieShape = CAShapeLayer() pieShape.path = UIBezierPath(arcCenter: CGPointMake(29, 29), radius: 27.0, startAngle: CGFloat(startAngle), endAngle: CGFloat(endAngle), clockwise: true).CGPath pieShape.fillColor = UIColor.clearColor().CGColor pieShape.strokeColor = UIColor.blackColor().CGColor pieShape.lineWidth = 4.0 self.layer.addSublayer(pieShape) let countDownAnimation = CABasicAnimation(keyPath: "strokeEnd") countDownAnimation.duration = durationInSeconds

To make it short: Do never ever give a project a frameworks name! I called my project "CoreGraphics". Original question: I cant use CoreGraphics in a newly created simple Single View Application I start Xcode 6.0.1 (6A317) New Project: Single View Application: Swift New File: Cocoa Touch Class "CustomView" of type UIView I uncomment the template for drawRect(rect: CGRect) {} Compiler Error: Use of undeclared type 'CGRect'. import UIKit is in place I tried to add CoreGraphics to "Linked Frameworks and Libraries" I already restarted Xcode (and my Mac) Update I installed Xcode 6.1 (6A1046a)

Is it possible to adjust color levels using Core Graphics? I would like to adjust channels using parametrized curves in the Gimp or other graphic editor style. You can use this: ios-image-filters (like photoshop) if you want to manipulate levels, here's your method, built straight onto the UIImage class: - (UIImage*) levels:(NSInteger)black mid:(NSInteger)mid white:(NSInteger)white 来源： https://stackoverflow.com/questions/7567934/ios-change-color-channels-levels-programmatically

I need to display the content of PDF files that i receive from a Web Service. My problem is that all PDF boxes returns the same value. Do you have any idea what can be wrong with the files i'm using ? CGPDFPageRef drawPDFPageRef = CGPDFPageRetain( CGPDFDocumentGetPage(pdf, 1) ); CGRect cropBoxRect = CGPDFPageGetBoxRect(drawPDFPageRef, kCGPDFCropBox); CGRect mediaBoxRect = CGPDFPageGetBoxRect(drawPDFPageRef, kCGPDFMediaBox); cropBoxRect = (0,0,595,842) mediaBoxRect = (0,0,595,842) When i display the PDF in a UIWebView the content is ok This is the PDF rendered by a UIWebView This is the PDF

This is a template image ( http://i.stack.imgur.com/9ME6A.jpg ) in which multiple circular area are available. we need, when we click on any circular area (one by one ) then gallery should be open and after selecting the image from gallery that image should be shown on the selected circular area. Please provide me any link or demo for my problem. i am stucking here. Thanks! Make a viewController with 5 "UIImageView" views. Arrange as you need it Place there your smile images. Add UITapGestureRecognizer into every UIImageView and catch them Open UIImagePicker and make your VC as a delegate