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

Answers For Aspiring iPhone Developers On Twitter

John — Thu, 16 Jul 2009 08:12:28 +0000

As some of you probably know I have a twitter account where I generally twitter about iPhone Development stuff. I’ve also thrown out answers to aspiring iPhone asking questions about iPhone development, and I’ve been asked some myself. Many of the same questions come up repeatedly, and some can’t really be answerd in 140 chars. so I’ve decided to create this page.

Just off the top of the head I’ve listed 10 questions along with my answers. If there’s a question you feel should be on here, or you think something could be answered better feel free to comment about it or tweet me about it.

Mini-FAQ for Aspiring iPhone Developers on Twitter

1. How much does it cost to be an iPhone developer?

Absolutely nothing, just go here, register an Apple ID if you don’t have one, sign in and click where it says to download the iPhone SDK. You will have to pay at least $99 to put the app you create onto an iPhone/iPod Touch.

2. Can I use the iPhone SDK/Develop in windows?

Simply answer no. Long answer: There may be ways to develop on a jailbroken iPhone using a Windows PC, but you will need to have a computer running Mac OS X at some point. Legally that will require a Mac.

3. Why doesn’t Apple let you use Windows to develop for the iPhone, wouldn’t that get them more apps?

Apple seems to be having even more App submissions than they can handle, and since the iPhone was released Mac OS X usage has more than tripled. I doubt they’re even thinking about it at all.

4. Can I develop for the iPhone in a virtual machine?

Apparently it goes against the OS X Eula to run OS X in a Virtual Machine. I’ve seen it tried, and honestly it ran like crap.

5. Can I run my apps on a jailbroken iPhone without paying the $99?

I have really no idea. How serious could you be about app development if you don’t want to pay the $99.

6. I really can’t pay the $99 or I don’t have an iPhone… how can I still develop?

The iPhone SDK comes with a simulator that you can (theoretically) use to test apps. Be aware this is not exactly like running an app on the iPhone, and many features can not be tested. You certainly would want to test an app on an actual iPhone before trying to distribute it anywhere.

7. What language do you need to use for iPhone programming?

Many components will require you to use the Obj-C messaging syntax. You can use C, C++, and Objective-C with the SDK without having to use anything outside of what Apple provides, and there are commercial and free products out there allowing you to use Ruby, C#, Lua, Javascript, and probably a dozen other languages. For games (which is what most people are really asking about) you can design nearly the entire game in C/C++ using virtually no Objective-C at all.

8. What books should I read?

Check out this post here. If you’re an absolute newbie to Mac/iPhone programming C is the place to start, and Programming in Objective-C 2.0 seems to be the consensus choice for absolute newbies. Beginning iPhone Development is the consensus "best book" at the present time for iPhone development.

9. How long will it take to learn iPhone development?

That’s a bad question, and honestly if you’re asking that question as a newbie iPhone development might not be your thing. Coming from Windows/Non-Objective-C programming might take a week or two for the basics. No one can really say how long it will take.

10. I have a great app idea, anyone want to develop it for me?

Sure, if you’re willing to pay or maybe if you’re an internet celebrity like iJustine or Chris Pirillo and will let me plaster my name all over the app.

That’s it, feel free to tweet this page if a buddy starts asking about iPhone development.

. Tags: 3gs, development, questions, ipod, iPhone, faq, 3g, touch, twitter

Code Snippet: Easy fading iPhone buttons, images, views

John — Wed, 15 Jul 2009 08:48:08 +0000

I was asked by a friend working on their first iPhone app if I could show them how to fade buttons to provide the user with visual feedback. So I came up with this quick iPhone development tutorial using some source code that is actually from the second app that we I will be showing how to build in my iPhone development videos.

A very quick demonstration of the effect is shown in this video:

Fading a view on the iPhone is very easy you simply specify the ending alpha value, and duration, and commit the animations. The views will then fade to the chosen alpha value. Overall it’s a pretty sweet way to fade buttons, and images used in your interface especially if you’ve had to go through more complex techniques.

The code for the two methods to create the buttons is shown here:

That’s all there is to it, it’s very plug and play so all you have to do is run the methods to perform the effect., and I’ve included some sample code with a project that has various views fading in and out based on which button is selected. With a little bit of playing around you can make flashing images/buttons etc.

The completed project can be downloaded here: >>> FadingViews <<<

. Tags: ipod touch, ipod, itouch, development, apple, effects, programming, animation, iPhone

Traffic Ranked Listing Of iPhone App Review Sites

John — Sun, 12 Jul 2009 08:07:09 +0000

This is a ranked listing of iPhone application review sites that accept applications submissions from developers. Getting listed on these sites can be a good way to gain exposure for your app, and every little bit helps.

I have filtered out sites that simply track iTunes feeds and list everything in the store.

The listings are ranked based on traffic given by the Compete.com rank.

http://toucharcade.com Compete Rank: 18,238
http://www.appsafari.com Compete Rank:27,893
http://appadvice.com Compete Rank: 38,515
http://www.appcraver.com Compete Rank: 39,759
http://iphoneapplicationlist.com Compete Rank: 56,764
http://www.appstoreapps.com Compete Rank: 88,622
http://www.gamestooge.com Compete Rank: 121,583
http://theapppodcast.com Compete Rank: 174,360
http://www.freshapps.com Compete Rank: 201,486
http://www.nativeiphoneapps.com Compete Rank: 345,031
http://www.iphoneblog.de Compete Rank: 1,141,082
http://www.apptheater.com Compete Rank: 1,171,181
http://www.appgallery.org Compete Rank: New
http://iphoneappgirl.com Compete Rank: New
http://www.theipodkid.com Compete Rank: New

If you know of any other good sites that accept app submissions for review please post them here. Thanks.

. Tags: sites, itouch, review, app store, iPhone, ipod, apple, app

Finishing With Interface Builder – Building Your iPhone Apps Interface Quickly 2/2

John — Sat, 11 Jul 2009 07:32:11 +0000

This is the second part of the tutorial on building your iPhone App’s interface in interface builder. In this video I quickly drag out all the elements, and connect the interface elements with the appropriate outlets, and actions, and build the class file automatically.

This is the 5th video/tutorial in this series, and I hope you enjoy it.

The first tutorial can be found here:
>>> Developing Your First Apple iPhone App <<<

The project containing the app at the end of this video can be found here:
Project file for tutorial

We will finally get into writing code in the next video!

Here it is:

Thanks for reading.

. Tags: iPhone, apple, programming, ipod, interface builder, ipod touch, getting started, development, developer, tutorial

Big List of Youtubers Who Will Review Your iPhone App

John — Thu, 09 Jul 2009 00:35:50 +0000

As many of you may have noticed, I have been updating my older resource lists with updated links that have been shared with me in the last few months since starting this site, and I’ve been uploading tutorials/other videos to Youtube.

One resource which I didn’t really think about was Youtube. I wasn’t really a Youtuber before uploading my videos, but something I noticed was that there is a massive number of people on Youtube doing app reviews. Usually developers will upload a usage video to Youtube, and ultimately that’s the end of things, it’s hit or miss, and most videos get very few views.

Why not send the App reviewers your apps? Many of these reviewers have already established a subscriber base of 10,000 or more on Youtube (along with nearly as many on Twitter), and I’m sure would be flattered if sent a promotional code. A couple who I have contacted seemed very excited about the idea. Also, many of these videos end up being shown on other sites so the effect can multiply.

I wouldn’t be turned off it appears that many of these viewers are members of the younger set, after all this is a large segment of the App market, and especially if you’re developing an entertainment app this likely is your market.

Don’t forget to mention if you have/know of an active channel in the comments.

Thanks for reading.

. Tags: app store, ipod touch, app, reviewers, iPhone, youtube, ipod, itouch, apple, review

Source Code: Particle Based Explosions In iPhone OpenGL ES

John — Sun, 05 Jul 2009 09:03:19 +0000

Hi everybody, if you’ve been following me on twitter you may have seen my tweet about an open sourced iPhone version of Space Invaders.

If you haven’t seen it yet, it’s a very concise implementation of the classic game, and also a very basic implementation, but I noticed something pretty cool while playing with it, and that was the particle based explosions. So what I did was spend about 3 minutes playing with the code, and I came up with the demo shown here in this video.

To create these explosions a Particle Emitter created by the guys at 71 Squared (makers of some great iPhone game development tutorials) along with a custom texture class.

To create the explosions a Particle Emitter is first created and initialized using the initParticleWithEmitter class, where you can specify parameters for the color, duration, size, number of particles, and gravity of the resulting display of particles (an example of this is in the EaglView.m file).

To display the particles a time index is created, and the update: method is executed along with the renderparticles method. I won’t go into the details here as the ParticleEmitter classes are extremely well documented.

Download the source code for the explosion generator here:
>>> Explosion Generator Source <<<

Have fun with the code.

. Tags: 3g, particle generator, ipod, 3gs, development, apple, particles, itouch, opengl es, iPhone