I have added sublayers to my UIView's layer. However, the root layer(UIView's layer) is visible at background as white rectangle. How can I effeciently hide superlayer so there will be no resourses spent on compositing with sublayers? ...
Hi. I am trying to work with images in Cocoa - open images and manipulate with them. I take ImageApp as example . All work fine, but I need to save images in lower quality -(8, 4, 2, 1 bits per pixel - 256, 16, 4, 2 colors respectively). According to documentation, the "lowest" pixel format is Gray 8 bpp, 8 bpc,kCGImageAlphaNone and i...
In one of my apps, I have a custom drawn semitransparent UIView that I use as a cover on top of another UIView for a special effect. Lower View: Lower View with Custom View on Top: It works, its great on the iPhone where the side margins are only 10 pixels, but now I need to expand the left and right margins to match the row below i...
Partly as a programming exercise, and partly because we may need to include such images in an app some day, I've been trying to figure out how to draw an image like the selected tab in a UITabBar. The basic operation is simple enough in concept: the icon's alpha is used as a mask to draw the blue gradient image onto the tab. (Though I c...
Is there any real need to do this: CGFloat x = 10.0f; CGFloat y = 20.0f; someView.center = CGPointMake(x, y); Instead of this: float x = 10.0; float y = 20.0; someView.center = CGPointMake(x, y); ...aside from style considerations? Are there any performance implications at all? ...
Hi all, I am implementing a graphic based application. I am very new to graphics, I need to display a dotted circle in my view. Is it possible to draw a dotted circle in using graphics, can you guys please help how to do it? Thanks in advance, S. ...