How to make iPhone app "skinnable"?

I was asked by a client to make a "skinnable" app and I don't really know what that means. I googled lik开发者_JAVA技巧e crazy and I didn't found a clear answer or an example.

If anyone has a clue about this, any tip would be appreciated.

Thanks.

Generally this means the app will allow the user to choose different looks for the UI, each of which will have a different color scheme, feel, etc.

What I actually did with my project. I decided to use multiple storyboards to give me greater control over the entire UI and UX of each theme. I programmatically link them all together via a master storyboard that links them all together. That's what I did, and it works very very well. Performance is great, while still maintaining high level of fine grain control over each theme. You can even keep your Header and Implementation files the same for individual view controllers, just so as you keep the names the same on the storyboard.

So for instance, one of my apps that I'm working on called Jam-mout (A music player) has multiple high quality themes. (Image attached). Each theme has it's own storyboard.

For iPhone apps, where the majority of the GUI design is provided by the operating system, you could do it by setting custom Navigation bar background images, custom button graphics, and different fonts/sizes/weights and whitespace. Make sure you're working with a designer who's familiar with the iPhone GUI (if you're not working closely with a designer this is going to be a nightmare).

I recently put together an app for a client who wanted a heavily customised GUI: http://itunes.apple.com/us/app/gogoparis/id428497937?mt=8. A 'skinnable' app would have several sets like this, so the user could choose between several different overall styles. (I hope your client has an enormous design budget!)

my post here should help you get started:

What is the recommended method of styling an iOS app?

if you need live theme changes, each theme in this example could post notifications when the user selects another theme (or skin) - then you can update either the theme instance itself.

alternatively, you can create identifiers for themes which are mapped (NSCFDictionary) to a central theme factory. an example identifier for a specific view for use with the theme factory could be a string MONImageSelectorTableCellThemeIdentifier.

an example manager/factory which handles all theme loading and vends references to themes:

@interface MONThemeManager : NSObject

//...

- (MONTheme *)themeForCurrentlySelectedSkinForViewWithIdentifier:(NSString *)identifier;

//...

@end

beyond that, it's hard to answer your question in more detail without knowing your requirements. the implementation of skinning an app can range from very simple to very very complex. good luck.

Already some good answer here, but I'd add that if you use a ui toolkit such as Three20 you can skin everything using CSS as you might for web pages.

I do realise this is an old post, but I thought I'd share my penny on the matter:)

To make any Cocoa app skinnable you need you think of 3 aspects of the app:

1) Uniformity: By this I mean that on all windows, views (including buttons, text inputs etc...) you want to have a 'standard' that will apply throughout the app. This is the first thing you need to look at. Although iOS and OS X alike already have 'themes' as to put it i.e. Apples default way of shading and laying things out, you can override these (refer to the individual view / window etc... documentation.

2) Performance: With skinning etc... performance is always an issue when it comes to writing your own drawRect etc... methods. The code apple have in place for the 'default' is already optimised, so you need to keep a close eye on the performance of the app whilst you are doing this. Good examples are: Do I use an image with a gradient, or do I use NSGradient? Both of which have performance issues when it comes to rendering them, but it's a question of which is the better of the two

3) userDefaults: This is generally the area where you'd be getting your 'skin settings' pulled from. userDefaults is basically where you store all of the information which you generally set in a preference pane.

If I were you I'd look into the class reference of it:

http://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSUserDefaults_Class/

Furthermore, here's a nifty example of using userDefaults:

http://mobile.tutsplus.com/tutorials/iphone/nsuserdefaults_iphone-sdk/

Hope this helps!