Adding “Invite Friend” to an iOS app
If you’re an iPhone user, you must be glad that there are apps for just about anything. In fact, as of this writing, Apple’s App Store website boasts that it now has more than 500,000 apps. Impressive.
Category Archives: Mobile
iOS: Creating a Spin Animation using Transitions
Animations are one of the cornerstones of the iOS platform. Animations can add polish and visual interest to any application.
iOS comes with many default animations and effects. An animation between two views is referred to as a transition.
On a recent project, we needed to create an animation of a card to make it appear spinning. Creating this effect from scratch would involve a fair amount of code, but leveraging transitions made it easy.
Picking an image from your Facebook photos in iOS
Apple provides a convinient class, UIImagePickerController, that easily allows your app to display a user interface to pick an image from the photo library. There are countless apps out there that utilize this class. Since this class manages all the user interactions, end-users of the apps that use it will find consistency when picking an image from photo library. Facebook iOS app, WhatsApp text messenger, Messages and Tweetbot are just a few popular apps that leverage this class. It’d be great had Apple provided a similar class for picking a photo from a Facebook account.
Google Android Translation Guide
If you are new to Android programming, you will find there are a few ‘new’ concepts and paradigms to learn. There are fancy new terms such as ‘Activity’ and ‘Intent’. Rest assured, most of these expressions are just Google trying to put their own stamp on some pretty tried and true programming paradigms.
Thumbnail View of a Large Number of Photos with Three20
Three20 is an open-source library for iOS applications. It provides many handy features that make your iOS development life much easier. It’s used in many popular iOS apps, including Facebook. One of the features that I’d like to discuss is the photo thumbnail view. Here’s a screenshot of TTCatalog app, a sample app that comes with Three20 project.
In-App Facebook Authentication on iOS
The official Facebook iOS SDK provides an easy way for any iOS applications to authenticate against a Facebook account. If you follow this tutorial, you’ll be able to add facebook authentication in your app in less than 15 minutes. It’s that simple. Once your app has been authenticated, it will possess both access token and expiration date. These two pieces of data will be used in subsequent communication with Facebook.
Android Pattern Lock on iPhone
I’m a loyal user of iPhone. I’ve been using it since its first version and now I’m on 4S. Though I’m staying in iOS camp and don’t have any intention of moving, I occasionally get the urge to test out and see what’s out there. That’s the reason why I convinced myself to own and play with Dell Streak 5″ phone and Google Nexus S. They are both smart smart-phones. But it’s hard to pick their pros and cons by simply “playing” with it. You’ve got to use it. Daily. For everything including surfing, speed dialing, social-networking and games. Everything. And that’s something that I didn’t get a chance to do until last summer when I was traveling and in need of an unlocked phone. I could make my iPhone work (don’t ask me how) but thought I’d give an Android phone a real kick.
Feel My Pain: NSXMLParser Problems Upgrading to the iPhone 3.0 SDK
I set out a couple of weeks ago to port the Killer Deals
application from the iPhone 2.2.1 SDK to 3.0. “No problem”, I thought; the
application doesn’t veer far from the standard APIs and controls, and it is a
relatively straightforward application, implementation-wise.
As I was making my updates (some minor method and property
name changes here and there), I stumbled upon a show stopper: The NSXMLParser
was no longer parsing my XML data. After scratching my head for a few hours, I
finally figured out the problem.
Dealing with JSON on iPhone
You can easily use the JSON (JavaScript Object Notation) data format in client-server communications when writing an iPhone app. This blog is not suggesting that JSON is a more superior format for data exchange than its counterparts such as XML. In fact, we have many projects that don’t use JSON. However, handling JSON is relatively straight forward in ObjectiveC.
Unfortunately, Apple iPhone SDK (as of this writing, the latest is iPhone 2.2.1) doesn’t come with a built-in JSON parser. But I found out a good one called json-framework. It is both a generator and a parser. As a generator, json-framework can create JSON data from an NSDictionary. As a parser, you can pass to json-framework an NSString that consists of JSON data and it will return a NSDictionary that encapsulates the parsed data.
Broadcasting Information: How to use the iPhone Notification Center
There are times when building an iPhone application that you
need to inform other parts of the program to do something, without regard to
what or where those parts are. The NSNotificationCenter (aka “notification
center”) is the way to go in these cases. Using notifications supports ‘loose
coupling’, which is a good thing in software design.
A notification center object provides a mechanism for
broadcasting information (“notifications”) within a task. An
NSNotificationCenter object is basically a notification dispatch table. For
those familiar with Windows programming, this pattern is similar to the Windows
Message Loop architecture.