Defining a custom gesture is tricky. The tricky part is being flexible when defining what constitutes a gesture . In our sample, we’re going to define a gesture shaped like a check mark.
Detecting Pinch is pretty easy. First, when the gesture begins, we check to make sure there are two touches,because pinches are two-finger gestures. If there are two , we store the distance between them. Then as the gesture progresses, we keep checking the distance between the user’s fingers, and if the distance increases or discreases more than a certain amount , we know there’s been a pinch.
Let’s look at using pickers that let the user select from a list values. In this example we are going to create an NSArray to hold the values we want to display in the picker.
This is the example of a Picker with two components or wheels, and each wheel will be independent of the other wheel. The left wheel will have a list of sandwich fillings, and the right wheel will have a selection of bread types.
We are going to have a little fun with the fifth content view. We’re going to see how to add image data to a picker, write a little game that uses a picker with five components.
There is one way of handling autorotation, and it’s an option you’ll likely only use in the case of very complex interface. We just design the landscape and portrait views separately and then swap them out when the phone is rotated.
We are going to write a slightly more complex application, one with two as well as a label. When the user taps either of the buttons, the label’s text changes. This may seem like a rather simplistic example,but it demonstrates the key concepts you will need to master the use of controls in your iphone application.
We are going to build an application that will take your knowledge of controls to a whole new level. We’ll implemented an image view, a slider, two different text fields,a segmented control, a couple of switches, and an iphone button that looks more like as an iphone button.
It’s most important to understand that each of these multiview controller is a view controller. Even the provided multiview classes UITabBarController and UINavigationController are subclasses if UIViewController and can do anything other view controller can do.
Detecting multiple taps is very easy to use. If the user triple taps, you get notified three separate times. You get a single-tap, a double tap and finally triple tap. lets see how it is worked.
This is going to be a very simple example of using the accelerometerto receive input.We are using Quartz 2D in this application for the sake of simplicity and reduce the amount of code that’s unreleated to using the accelerometer.
Book your seat today and mark your calendar! The first of a series of Free iPhone Programming Webinars will be held on 6th and 13th February 2010. People from all backgrounds are intrigued by the possibility of writing their own iPhone applications. Unfortunately, they often don’t know where to begin. Head Tutor at EDUmobile shows you just how easy it really is.
Xcode offers a perfectly good template for creating navigation-based applications, and you will likely use it much of the time when you need to create hierarchical applications. We are going to construct our navigation-based application from the ground up so you get a feel for how everything fits together.
Quartz 2D is an advanced, two-dimensional drawing engine available for iPhone application development and to all Mac OS X application environments outside of the kernel.
This application used both Portrait and Landscape mode. I will show you how to change that orientation at runtime.
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