Some time ago I wrote a blog post about working with gzip compressed files on iPhone. Interestingly, it is one of the most frequently viewed posts on this blog according to the stats. Recently, one of my readers send me an email asking to post an example how to download a ZIP file from the web, uncompressing it and saving the result to the local file system. I decided to go through the code of one of my iPhone app prototypes which does exactly this task. In this blog post I briefly outline the steps to accomplish the goal. (more…)
Archive for the ‘iPhone Development’ Category
Downloading and uncompressing ZIP files
Saturday, February 7th, 2009Increasing tapable area of accessory view
Saturday, February 7th, 2009The history view of TimeTracker which was introduced in version 1.1 and is accesible through the so-called detail disclosure button. Unfortunately, the default size of the tapable area which causes the history view to be shown is very small. This lead to complaints by our users because timers are started and stopped accidently if the user intended to view the history. One goal for version 2.0 is to circumvent this limitation. In this post I’ll describe a way how to increase the tapable area of the accessory view. (more…)
Conditional Debug Output
Tuesday, December 23rd, 2008When developing applications it is very common to log things to the console to print out information. To do this NSLog() is used whenever there is valuable information to print out. When you come to point where you want to actually release the application to the public or at least your group of beta testers you do not want the application print out all the details. One solution would be to remove all the NSLog() statements from the code. Of course, this is very time-consuming and you might forget to remove some of the log statements. A better way would be to let the preprocessor do this automatically. (more…)
App Store listing order
Tuesday, October 7th, 2008Last week, Apple published changes to the App Store. There’s a really great article at AppleInsider which provides details about the changes.
One of the changes affects the way applications are listed in their category. There’s a good blogpost by Krishna Vegesna which describes the consequences of the previous ordering of the applications. With the latest changes to the App Store applications are sorted by the date they were first release now. However, the release date can be easily changed by the application developer via the iTunes Connect website. The related form field can be found on the “Pricing” tab when editing the application information. Changing the date almost immediately results in updates to the App Store.
To see if there is an actual loop hole I have set the release date for TimeTracker to October 7th this morning. And indeed there is a problem! So this could be easily exploited by developers who want to push the sales of their applications artificially.
However, the changes to the release date seems to affect only the sorting of the application in its primary category which is a little confusing, too.
I hope that Apple will offer a solution to this problem soon to provide the same chances to all developers and all the apps on the store!
Collecting App Store Reviews
Tuesday, September 23rd, 2008Once your application is on the App Store users can leave comments to let you know what they think about your product. That is a really great thing to get in touch with the users in an easy way.
The only drawback is that the developer is not able to access these comments in one single place. Instead you have to switch to each single country in iTunes, go the the App Store and open the product page of your application. Then you are able to read the reviews for this country. This is very time consuming of course. It gets even worse if you have more than one application for sale.
I always thought about writing a little script to access the product page of my application for each country and get the reviews directly. Because the communication between the iTunes frontend and the backend systems at Apple is based on XML I thought that this should be possible to do. Unfortunately, I never found time to actually work on this idea.
This morning I browsed the Apple Developer Discussion forum and came across a thread which discusses this topic. And there I found a blog post written by Erica Sadun which describes a Perl script which does exactly the thing I wanted to have. I have not tried it yet but it looks very promising!
Using NSDateFormatter
Monday, September 22nd, 2008When I was working on TimeTracker and another iPhone application which is not released yet – and may never will be – I struggled with the usage of the NSDateFormatter. Although I think the documentation Apple ships with their development frameworks is pretty good in general I could not figure out how to use the formatter correctly. (more…)
Working with gzip compressed files on iPhone
Sunday, September 14th, 2008Recently, I had the requirement to unzip files downloaded on my iPhone. Luckily, the iPhone supports zlib for doing compression and uncompression. Unfortunately, there is no elegant and easy to use Objective-C wrapper. So you have to fall back to plain C programming. (more…)