Tutorial: Intro to Core Animation. Author: David Gohara Web Site: gohara.wustl.edu Core Animation, you've been hearing about how great it is, how it makes animation easier and how cool it is.
Well you're about to find out first hand that all of the things you've heard are TRUE. We'll cover a little background first and then jump into a simple Cocoa example on how to build Core Animation functionality into your application using a couple of completely contrived examples (For those that want something a bit more advanced, I've posted some work-in-progress code, that shows how to use layering to create a cheap Cover Flow knock off.
Hey it's a work in progress. See the end of the tutorial for links). Layer.frame not updated after CAKeyframeAnimation? - Stack Overf. How to create iphone's wobbling icon effect. Mac Dev Center: CAKeyframeAnimation Class Reference. Overview The CAKeyframeAnimation class provides keyframe animation capabilities for a layer object.
You create an CAKeyframeAnimation object using the inherited animationWithKeyPath: method, specifying the key path of the property that you want to animate on the layer. You can then specify the keyframe values to use to control the timing and animation behavior. For most types of animations, you specify the keyframe values using the values and keyTimes properties. During the animation, Core Animation generates intermediate values by interpolating between the values you provide. Properties biasValues An array of NSNumber objects that define the position of the curve relative to a control point. @property(copy) NSArray *biasValues Discussion This property is used only for the cubic calculation modes. Availability. Watching Apple: Core Animation: Creating a Jack-in-the-box with. A previous example demonstrated how CAKeyframeAnimation can move layers along a CGPath, but CAKeyframeAnimation can also move a layer through a succession of points with a custom timing for each point.
You might animate a pendulum with two points representing the extreme limits of its swing, for example, easing the pendulum into and out of each swing. But pendulums are boring—so let’s animate a Jack-in-the-box instead! Our Jack-in-the-box will be simple: just a box and lid containing a spring with a clown’s head attached. When you close the box, the spring and head are hidden inside. And when you open the box, the lid flies open and the spring and head bounce out. These motions require 4 animations: The lid of the box opens with enough force that it bounces back, then gradually settles into its open position.
We’ll use CAKeyframeAnimation for each of the animations. The head sits “on” the spring, so jackLayer lies above springLayer on the z-axis. Opening the lid 1. Bouncing the spring. How do I chain scale animations with an iPhone UIImageView? - St. How to stretch the image size in iphone UIImage or UIImageView - iPhone Programming - Easy Image Animation. iPhone Dev Center: CGAffineTransform Reference. Functions CGAffineTransformConcat Returns an affine transformation matrix constructed by combining two existing affine transforms.
CGAffineTransform CGAffineTransformConcat ( CGAffineTransform t1, CGAffineTransform t2 ); Parameters t1 The first affine transform. t2 The second affine transform. Return Value A new affine transformation matrix. Discussion Concatenation combines two affine transformation matrices by multiplying them together. Note that matrix operations are not commutative—the order in which you concatenate matrices is important. Availability Available in iOS 2.0 and later. Declared In CGAffineTransformEqualToTransform Checks whether two affine transforms are equal. iPhone Dev Center: Core Animation Programming Guide: Introductio.
iPhone OS Reference Library. Demystifying CGAffineTransform. One of the most common questions I get about iPhone programming is about how to rotate or scale or make various other changes to a view.
I'm not talking about hardcore Core Animation kind of stuff, just simple, "How do I place a label at 45°" kind of questions. The expectation is that there should be a property called "angle" or "scale" that can be set, or that you should be able to hold down the option key in Interface Builder to rotate it there. With Leopard, Apple gave us Core Animation,and it is very cool, but in order to achieve all that coolness, they had to add some concepts that make it not always intuitive.
(BTW: If you do want to know more about Core Animation, I've been reading Bill Dudney's Core Animation for Mac OS X and the iPhone and it's very good). Any change to a view's position, scale, or rotation can now be stored in a property of the view called transform. iPhone Dev Center: UIView Class Reference. Overview The UIView class defines a rectangular area on the screen and the interfaces for managing the content in that area.
At runtime, a view object handles the rendering of any content in its area and also handles any interactions with that content. The UIView class itself provides basic behavior for filling its rectangular area with a background color. More sophisticated content can be presented by subclassing UIView and implementing the necessary drawing and event-handling code yourself. The UIKit framework also includes a set of standard subclasses that range from simple buttons to complex tables and can be used as-is.
Because view objects are the main way your application interacts with the user, they have a number of responsibilities. Drawing and animationViews draw content in their rectangular area using technologies such as UIKit, Core Graphics, and OpenGL ES.Some view properties can be animated to new values. Tour d’horizon du développement iPhone. Article paru dans le magazine Programmez le 30 Juin 2009. Avez-vous vu les dernières publicités pour l’iPhone ? Apple ne met plus en avant les qualités de son téléphone mais communique exclusivement sur les applications. Alors, comment ça se code au juste ce genre d’applis ?
L’AppStore est la plateforme de distribution d’applications pour iPhone, lancée par Apple il y a un peu moins d’un an au travers de son magasin en ligne iTunes Music Store. Il permet à n’importe qui de potentiellement vendre son application aux millions de possesseurs d’iPhone. Prêts à vous lancer dans l’aventure ou juste curieux ? 1. Un mac Avant de se lancer tête baissée dans le code, il convient de rappeler certains pré-requis. Le SDK est téléchargeable gratuitement et le site Apple Developer Connection regorge de documentation, de vidéos et d’exemples. How to create iphone's wobbling icon effect.