Question

I have an Android project I’ve inherited from another developer.

The original code was hacked together using a single View and a single Activity. The view class has a State variable that is switched on during input and rendering.

Each “screen” is a single bitmap rendered directly onto the screen. There are no layouts used at all. To make things even worse each variable in both the View and Activity classes were all declared public static and would access each other frequently.

I’ve reworked the code so it is now somewhat manageable, but it’s still in those original two classes. This is my first decently sized Android app so I’m not completely sure where to go next.

From the looks of things, each “screen” should have its own View and Activity. Is this the general practice?

If so I need some way to share data between the separate Activities. I’ve read suggestions to use a Singleton class that holds generic data. Is there any other ways that are more built into the Android framework?

Thanks in advance.

Answer 1

I would recommend using one activity per screen, or rather, per function. An activity generally has one associated view that draws the UI. If all the activity does is display different bitmaps, than you can define an ImageView in the layout and display the various bitmaps in that ImageView.

Using public static fields is bad practice in Android Activities. Activities should not access fields in other Activities at all, they should pass data to one another through the intent, or via a database, or via shared @Injected classes.

From what you write, it may be easier to start that app again from scratch, than to try to fix the current app. I have been there, done that, afterwards regretting not scrapping the app and starting from scratch.