iPhone Dev Sessions: Making a Splash Screen
All too often an iPhone application’s launch sequence is an overlooked detail. The most common approach is to misuse the provided Default.png file as a splash screen. As it turns out, this detailing of an application is more than a little challenging if you want to get it right and stay within Apple’s guidelines.
The key to a smooth and professional looking launch sequence starts with knowing exactly where the application will land at startup. Some applications start at exactly the same place each and every successive launch, others attempt to preserve the application’s state and launch into the screen where the user last used the application. Keeping this in mind can change the strategy of how the launch sequence is implemented. This includes screen orientation as well as how and even if the status bar it to be displayed.
One may witness flickering of the status bar from blue, to black or from black to blue during the launch sequence. This is mainly due to the fact that there are two places to change the behavior of the status bar. One is hidden in the info.plist file, and the other is typically via code in the Application Delegate’s applicationDidFinishLaunching method. Theinfo.plist configuration is used before the main window is loaded, and the code in the Application Delegate is used during the launching of the main window. The reason one may want to utilize both styles is to take advantage of a full screen splash page, and then enable the appropriate looking status bar once the application has finished loading.
For the purpose of this example application, we will assume that the user state is preserved between executions, and we do not know exactly what the screen will look like when the user enters the application. We will therefore be implementing a full-screen splash view that will have the status bar hidden during the launch sequence. Once the splash view has disappeared, a black opaque status bar will be utilized throughout the application. It is also assumed that the application will launch in portrait mode, and that the first screen the user will see will also be in portrait mode.
Editing the Configuration File
The first order of business is to take care of the status bar. In Xcode, locate theinfo.plist file for the project. To add an additional property to the plist file, simply select one of the entries and click on the plus tab that appears to the right and select Status Bar Style from the drop down list:
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