iPhone, iOS 5, iPad SDK Development Tutorial and Programming Tips » Tag: iPhone

Best Resources In iOS Development – July 25th 2011

John — Mon, 25 Jul 2011 06:19:20 +0000

Another week gone by, and welcome to this listing of resources shared in the last week in order of popularity.

This week once again yet another beta was released of iOS 5 for us to install. The release date is slowly creeping up.

Some great resources were posted on the site including open source libraries for interface improvement, free game graphic sources, and some excellent tutorials.

If you would like us to submit a resource you can do so on the submit page.

Open Source: Drop In UILabel Replacement For Beautiful Text Easily - A library utilizing NSAttributedString, and core text allowing you to quickly create labels with styled text.

Design: Free Game Graphic Sets Made Specifically For iOS Games - Some great looking sets of game art styled specifically or the iPhone and iPad complete with backgrounds, characters and game objects.

Tutorial: Easy Game Controls In Cocos2D With SneakyInput - Describes how to use the SneakyInput library in your Cocos2D game so you can quickly add a virtual joystick.

Tutorial: Using And Building OpenCV (Open Computer Vision) On iOS Devices - Tutorial along with a build script for those looking to use the OpenCV library in their apps.

Open Source: Behavioral Driven Development Testing Framework - A framework made with Objective-C and specifically for Objective-C apps enabling BDD testing.

Tutorial: Objective-C Blocks (Closures) For Beginners - The basics of using Objective-C blocks including an overview of using them in concurrency programming.

Tutorial: Building Complete Games With SpriteHelper And LevelHelper - A couple of tutorials on the usage of these excellent tools to quickly build games with Cocos2D and Corona.

Open Source: Real-Time Congress App Phonegap And Native Source Code - The source code to both a Phonegap and native app that displays real time data.

Tutorial: Texturing 3D Objects In OpenGL ES 2.0 - An excellent step-by-step tutorials for beginners to OpenGL ES demonstrating how to Texture 3D objects.

Design: Creating An App with HTML/CSS And Sencha Touch - A tutorial on how to design iPhone style interfaces with HTML/CSS and Sencha Touch.

Thanks for reading, please bookmark and share this post!

. Tags: phonegap, iPhone, opengl es, ipad, open computer vision, programming tutorial, objective-c, opencv, open source libraries, ios

Tutorial: Texturing 3D Objects In OpenGL ES 2.0

John — Wed, 20 Jul 2011 18:38:31 +0000

OpenGL ES is a topic that I’ve posted about many times on this site, and I’ve been trying to keep a categorized list of OpenGL ES tutorials up to date with every OpenGL ES tutorial I’ve seen. There have not been too many OpenGL ES 2.0 tutorials to date that go beyond the absolute basics.

Previously I mentioned a good series on OpenGL ES 2.0 that gave a great overview on beginner through advanced topics with some sample code. I also mentioned a great hands on beginners OpenGL ES 2.0 tutorial from Ray Wenderlich, the creator of the Space Game Starter Kit and co-author of the Learning Cocos2D book,.

Ray has continued on with his tutorial series, and added another tutorial explaining how to texture objects in OpenGL ES 2.0 on iOS devices. Texturing may sound like something simple, but the process of loading in the textures, and extracting the data from memory makes things somewhat stick on the iPhone and iPad.

You can find the tutorial here:
OpenGL ES 2.0 for iPhone Tutorial Part 2: Textures

Definitely some very handy snippets of code if you ever need to do your own texturing in OpenGL ES 2.0.

Added To The: Categorized OpenGL ES Tutorial Collection

. Tags: opengl es 2.0, programming, texture objects, Graphics, opengl es, ipad, ios (apple), iPhone, opengl

Design: Creating An App with HTML/CSS And Sencha Touch

John — Wed, 20 Jul 2011 06:09:31 +0000

As you probably know there are many frameworks that allow you to develop native iOS apps with the interfaces designed with HTML/CSS.

The big question then is how do you create that app’s interface? Sencha Touch is one possibility.

I’ve found a tutorial that goes into detail on how to design a great looking mobile web app that looks like a native one using HTML/CSS using the Sencha Touch library that looks and feels just like a native app. What I really like about the tutorial is that it goes through the design process step-by-step.

The tutorial is from Jen Gordon who’s set of beginner native iOS app design tutorials I previously mentioned.

You can find the tutorial here:
Create An HTML/CSS Mobile Web App Using Sencha Touch

You can test out an expanded version of the app built in the tutorial here (use your iPhone):
http://senchalearn.github.com/roookies/?style=demo

This information is great to know not just for web apps, but a useful guide if you plan on creating a native app using a wrapper framework like Phonegap.

. Tags: design tutorials, ios (apple), Sencha Touch, tutorial, web apps, Mobile Web, javascript, html css, iPhone, sencha

Open Source: Real-Time Congress App Phonegap And Native Source Code

John — Tue, 19 Jul 2011 19:25:03 +0000

As you may have noticed I like to keep a list on this site of open source ios apps.

Earlier I received a submission of the url to an open source iPhone app that updates on what is happening at the US congress in real time, and provides access to data about members of the US Congress.

Politics aside, it provides an example of an app that retrieves and organizes data from an online source, and there is also a Phonegap version if you are looking for any html/javascript enthusiasts out there looking for a starting point trying to build with Phonegap.

You can find the source code for the newer native version here:
https://github.com/sunlightlabs/realtimecongress-ios

The source code for the previous Phonegap version can be found here:
https://github.com/sunlightlabs/real_time_congress-iphone_html

You can find the app on iTunes here.

I’ll be adding it to the list of open source apps soon.

. Tags: phonegap, itunes, programming, github, native source code, iPhone, source code, open source

Tutorial: Using And Building OpenCV (Open Computer Vision) On iOS Devices

John — Tue, 19 Jul 2011 06:46:13 +0000

If you have any interest in computer vision or augmented reality with marker detection then you have probably heard of OpenCV, the Open Source Computer Vision library for real time computer vision.

There are many apps, and some augmented reality libraries (even commercial ones) that use the BSD licensed OpenCV. However, building for iOS was a real pain, and for awhile it almost seemed like some wanted to keep the entire process secret (can’t really blame them!). I mentioned a tutorial that explained the process but definitely didn’t make things easy.

I recently came across a build script that alleviates all that pain so you can have OpenCV installed for iOS devices automatically, and it’s been updated to support OpenCV 2.2.9. The build script is from Khvedchenya Eugene and in the second part he writes on getting started with OpenCV in Objective-C.

Update: If you don’t mind precompiled binaries Khvedchenya has a precompiled iOS binary also available of OpenCV 2.3RC (thanks for telling me Tom!).

You can find Khvedchenya’s tutorials here:
Building OpenCV For iPhone In One Click
Using OpenCV In Objective-C Code

You can find the Github for the most recent version of the build script here:
https://github.com/BloodAxe/OpenCV-iOS-build-script

[UPDATE] For those interested in OpenCV 2.3 pre-compiled binary:
OpenCV 2.3 Release Candidate Is Available

If you ever want to dabble in augmented reality on iOS devices this is a great help.

. Tags: open computer vision, opencv, augmented reality, computer vision library, iPhone, ios

Open Source: Easy Multistroke and Single Stroke Complex Gesture Recognition On iOS

John — Fri, 15 Jul 2011 18:55:14 +0000

If you’ve ever wondered how to code gesture recognition for complex shapes I’ve come across a couple of open source libraries that should be a great deal of help. This goes well beyond finger swiping.

This library is based on the $1 gesture recognizer which I remember being discussed quite a bit a few years back because not only did it run efficiently, but allowed you define the templates to recognize complex shapes very easily. The $1 gesture recognizer only recognizes 1 single stroke from the user. The $1 gesture recognizer was later expanded on to become the $N multistroke gesture recognizer.

Brit Gardner has taken the $N gesture recognizer and created an Objective-C implementation of the code.

You can read about complex gesture recognition, and why Brit decided to use the $N gesture recognizer on his site in these posts:

Complex Gesture Recognition in iOS – Part 1: The Research
Complex Gesture Recognition in iOS – Part 2: The Implementation

You can find Brit’s Github for the Objective-C $N gesture recognizer here:

https://github.com/britg/MultistrokeGestureRecognizer-iOS

Adam Preble has created an implementation of the $1 gesture recognizer which can be found here:

https://github.com/preble/GLGestureRecognizer

You can try out the javascript versions, check out the full pseudocode, or download other versions of the gesture recognizers from the University of Washington here:

The $1 Gesture Recognizer
The $N Multistroke Gesture Recognizer

I’ve received e-mails a couple of times over the years asking about how some drawing games were created on the iPhone. If you are looking to make that kind of game this should help give you a head start.

. Tags: iPhone, multistroke, gesture recognition, ipad, open source, ios

Open Source: Active Record For Core Data Library

John — Wed, 13 Jul 2011 18:53:56 +0000

If you’ve developed with Ruby On Rails or similar framework then you are familiar with ActiveRecord, and you are familiar with how useful ActiveRecord is. I remember thinking how cool it was when I first played with RoR and began using ActiveRecord.

For those unfamiliar with RoR here’s the Wikipedia definition for Active Record:

Active record is an approach to accessing data in a database. A database table or view is wrapped into a class. Thus, an object instance is tied to a single row in the table. After creation of an object, a new row is added to the table upon save. Any object loaded gets its information from the database. When an object is updated the corresponding row in the table is also updated. The wrapper class implements accessor methods or properties for each column in the table or view.

I’ve come across an excellent open source library based on the Ruby On Rails implementation of ActiveRecord from Saul Mora for Core Data retrieval known as MagicalRecord.

You can find the Github for the project along with full instructions here:
https://github.com/magicalpanda/MagicalRecord

You can read Saul’s writeup on the project on his site here:
Magical Panda releases ActiveRecord Fetching for Core Data code library

If you want the full read on Active Record from Wikipedia here:
http://en.wikipedia.org/wiki/ActiveRecord

A very useful library indeed.

. Tags: core data, library, ios, iPhone, active record, ipad, magical record

Tutorial: Manipulating Images With Touch Gestures

John — Wed, 13 Jul 2011 06:22:50 +0000

You’ve already seen this in numerous apps. Images that can be dragged by holding, enlarged, shrunken and rotated with the pinch gesture. All that being said, if you’re new to programming UIGestureRecognizers this can be a somewhat difficult task.

I’ve found a tutorial demonstrating how to easily include this functionality that is immensely useful for many different kinds of photo apps.

There is also an excellent sample project included.

The tutorial is from Roger Chapman and can be found here:
iOS Image Manipulation with UIGestureRecognizer: scale, move, rotate

Tremendously useful code if you are ever making any sort of photo manipulation app.

[via Alex Curylo]

. Tags: iPhone, touchmove, tutorials, touch gesture, image, gestures

Tutorial: iOS Multithreading With Grand Central Dispatch (GCD) Basics

John — Tue, 12 Jul 2011 18:38:19 +0000

As a user it can be extremely frustrating if you’re using an application and you have to wait an extended period of time while the application updates.

Sadly this was pretty common when the app store was new. The devices were slower, the networks were slower, and many apps weren’t using multi-threading in places they probably should have. I remember becoming frustrated many times using an RSS reader, waiting for the article list to update, and then waiting again for the article to display.

Thankfully Apple introduced Grand Central Dispatch (GCD) with iOS 4.0.

Multithreaded programming with GCD can still be intimidating. I’ve found a great step-by-step guide which breaks things down into a step by step guide explaining things fully every step of the process of downloading data asynchronously and updating in real time.

The tutorial is from Ray Wenderlich, the creator of the Space Game Starter Kit and co-author of the Learning Cocos2D book, And Can Be Found Here:
Multithreading And Grand Central Dispatch On iOS For Beginners Tutorial

An excellent example of a tutorial that makes a complicated subject seem so simple.

. Tags: multithreading, ipad, Grand Central Dispatch, tutorial, gcd, ios, iPhone

News: Moai SDK Game Development Kit Made Available To All

John — Tue, 12 Jul 2011 06:48:16 +0000

A few weeks ago I mentioned the Moai SDK. An open source iOS game development kit allowing for development of iOS apps (and Android apps) in Lua. What I really liked about the engine that it has already been used in could be extended to support any functionality within the iOS SDK.

At that time Moai a limited beta, the beta has been extended now to support all developers.

In order to download the latest SDK release and the cloud services you will need to sign up on the Moai website for the dashboard here:
http://dashboard.moaicloud.com/signup.php

You can find the Github project for the Moai SDK Source here:
https://github.com/moai/moai-beta

The cloud services look great, and very easy to code – if you’re interested be sure to check out their 60 second tutorial here:
60 Second Moai Cloud Tutorial

There are numerous improvements since I first mentioned the SDK. Looks like the guys developing the Moai SDK have been very busy!