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Best Resources In iOS Development – July 18th 2011

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Another excellent week to be an iOS developer, and some big news in the department of iOS game development with the release of  Cocos2D V1.0.0 and the opening of the Moai SDK beta to everyone.  Also some great open source libraries and tutorials were shared.

If you have written a tutorial, open source library or tool that you would like to share you can submit the url here.

I’ve been contacted a number of times about advertising on this site so I decided to add support for BuySellAds, and added a section for small button ads.  If interested you can check out the advertising page here.

Here are the resources from the last week in order of popularity:

Open Source: Easy Multistroke and Single Stroke Complex Gesture Recognition On iOS – A couple of great libraries if you are looking to quickly implement complex gesture within your app.

Open Source: iCade Library For Easy Integration In iOS Games – Library that allows you to easily support the iCade classic arcade box/controller for iPad.  Makes a good example if you are trying to support a specific bluetooth interfacing device.

Tutorial: Manipulating Images With Touch Gestures – A tutorial with sample code demonstrating how to add touch features for image manipulation.

Tutorial: iOS Map Kit For Beginners Guide – A getting started tutorial for those beginning with the iOS map kit including a tutorial on displaying data from XML locations on a map without using any libraries outside of those included with  the iOS SDK.

Open Source: Active Record For Core Data Library – A great open source project modeled after Ruby On Rail’s ActiveRecord for more straightforward data retrieval.

News: Cocos2D Game Engine v1.0.0 Released – News about the highly popular Cocos2D game engine finally reaching the v1.0.0 release.

Tutorial: iOS Multithreading With Grand Central Dispatch (GCD) Basics – An excellent step by step guide beginning with the basics on multithreading with iOS ‘s Grand Central Dispatch.

News: Moai SDK Game Development Kit Made Available To All – The lua based open source Moai SDK has now opened the beta for anyone to download and use.

Tutorial: Calculator App Style Glossy Buttons With Core Graphics – An explanation of the technique used to create buttons just like the calculator applications that come with iOS devices.

Tutorial: How To Use The iOS Keychain To Store Names And Passwords – A guide on using the iOS keychain in order to securely store usernames and passwords.

Thanks for reading, please bookmark and share this post!


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Tutorial: Calculator App Style Glossy Buttons With Core Graphics

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In the past I’ve posted about creating iOS style buttons mentioning this tool, and this library which allow you to draw glossy buttons similar to those found in most iOS apps.

The basic calculator app however has different buttons.  They have a rounded gloss at the top, and a steady gradient all the way down the button.  You may have noticed when using the app that when you press the buttons there is a much more noticeable effect as the button look seems to reverse giving the impression that the finger has caused the button to reverse.

A developer named the Code Padawan has written up a quick tutorial, and provided sample code demonstrating how to duplicate this effect.

You can find their tutorial here:
iPhone Glossy Buttons

The effect is done entirely using core graphics so no need to break out Photoshop or any other tool.

[via Ole Begemann]


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Open Source iPhone App Store Apps Listing Updated

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The open source iPhone app store apps listing has been updated

Two iOS apps have been added:

  1. Tweetee – A fork of the Natsulion twitter client with many added features such as Twitpic integration, tweet trends, and link saving.
  2. SpaceBubble – A space game created using Core Graphics.

I’ve also updated the link to the Wikihow source code.

There are now 37 apps on the list which you can find here:
Open Source iPhone App Store Apps.


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How One Developer Went From 40 To 1000 Downloads In A Day

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Let’s face it.. getting app downloads is tough. There are over 200,000 apps out there, and it is very easy for an app to fade into obscurity.

Even free apps can suffer from this, you really have to get the word out there, and there are many different approaches.

One approach that has worked for one developer was to take their app, and release the source code. With so many people interested in iPhone development the app was able to go from 40 to about 1000 downloads in a day.

The app is SpaceBubble from Nick Vellios for which the iTunes link can be found here along with the source code.

The source code will be added to the Open Source iPhone App Store Apps listing.

[Source: Vellios.com]


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How To Draw Objects With Holes Using CoreGraphics

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Sometimes you will want to draw a more complex shape in an app that doesn’t use OpenGL, and you don’t want to load in the graphics from a file, and this can be done using CoreGraphics.

A situation that can arise is the drawing of one shape within another shape. The easiest way to do this is simply to draw the shape on top of the other shape, but this typically will not give the most efficient performance.

Also, there could be a situation when you want the user to see the background through the shape that you are drawing, and if that background is changing simply drawing shapes over top of each other isn’t going to cut it.

For those situations Matt Gallagher from Cocoa With Love has created a tutorial explaining 5 different techniques for drawing a shape with a hole in core graphics.

For more information on CoreGraphics check out our Resources for Learning Core Graphics and review of  the Core Animation Simplified book.

Please Click Here To Share This Article With Others By Re-Tweeting It.

[Source: Cocoa With Love]


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