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Prerequisites

1) image editing software (i.e. Adobe Photoshop or gimp)

2) DiskAid. although SSH will do a fine job, disk aid is faster and easier making it perfect to use for theming. there is a pull down menu in the bottom right that will allow you access to your root folder

3) a jailbroken iPhone or iPod touch with winterboard installed.

4) patience and time

Theme structure

The way winterboard is designed you must make your theme is a certain manner otherwise it will not work. The first thing is to make a folder on your desktop and call it whatever you like. Now open it

This folder is the main hub of your future theme. when jay freeman wrote winterboard he made it so that applications are accessible in two fashions. one is thorugh folders and one is through bundles. in most cases you will end up creating two folders automatically inside your theme called "Bundles" and "UIImages".

1) Starting with the bundles folder. these access points are defined by the bundle identifier (i.e. com.apple.springboard) these can be found if you navigate to applications folder in your iphone's root file system. You will see a file in any application called "info.plist". plist stands for Property List and these are used to tell information about the application. the thing we are interested in is the Bundle identifier. to find this you will want to find the application in diskaid and doubble click on info.plist. in Mac OS X it will open in the built in plist editor. in windows it will open in your default text editor. you want to remember the line starting with "com." everything afterwords will change depending on the application.

Bundle identifier in plist editor (OS X)

Bundle identifier in Text Editor

To use this name just make a new folder inside Bundles titled your Bundle identifier (i.e. com.sadun.AppFlow) then you will be able to change all of the .png images inside that application by naming it exactly what it is in the app, take note that some apps theme better tan others and it simpily depends on the app.

2) UIImages are where alot of the major theming like the keyboard and the background behind the sliders happens. these images are not found in any one place, they are scattered all over the phone. luckily you will not have to search for them and i will not have to list them. (see end of guide for UIImages explained.)

3) Like i mentioned before that there is always two routes to accessing all of the app images. here is the second. to use these make a folder called "Folders" in the main theme. inside that you will need to make folders titled the exact same as the app that you would like to theme. and After you are done adding in your images add on the end the extension ".app" in OS X the icon will change and you will have to right click and show package contents to change things from that point on. again luckily alot of these folders are explained in the iphone theme linked to at the end.

4) in that main folder also you will put your files "Wallpaper.png" "Dock.png" "LockBackground.png" and a few others. again explained in iphone theme

File Format and Images

the one main thing that you need to know is that when saving an image you will need to make sure that it is a ".png" if it is anything else the image will not be replaced. i am not going to tell you how to use photoshop or gimp in this guide but if you need help there are plenty of great tutorials out there.

once you finish your theme the final product will go into Library/themes

info.plist

eventually you will come to a point where you want to start manipulating the system and some minor tweaking like that can be done using the info.plist files. the main plist is in your main theme, you will want to base yours off of someone else's so that you have a good idea of how to do it (some great examples are in the pre-installed themes made by saurik in Library/themes. with these files you can only learn from examples. some examples of things you can do with these files are:

- moving the status bar position to landscape - changing font colors - removing the labels from icons

Using 3rd party Applications

some great assets to themes are apps like "SpringJumps" "5 Irows" "Five icon Dock" "Five Column SpringBoard" these apps can be used in your favor to not only make your theme look good but to add functionality to it. remember that the main goal in theming is to change the User INterface but also make it function just as well if not better. Use your creativity to decide which apps to use and when.

Closing

There is really no ONE way to make a theme but the real point in this guide is to give you the knowledge to allow you to go off and express your creativity. things are always changing and new ideas are being thought of everyday, so now that you have that knowledge you are able to come out of this and think of new concepts and contribute to the ever growing interface modification community.

Essential Links

Complete iPhone/iPod Image Theme

2.0 UI Images Explained