How to use Hardware Acceleration
Did you know Android has Hardware Acceleration? Did you also know you actually need to enable it for your app first? Suprisingly you do! It’s not defaulted to on. Here’s another little gem in Android that could have a major impact on your application.
If you allow your app to run on Android versions above 3.0, you should probably enable Hardware Acceleration. By enabling Hardware Acceleration, the performance of your application’s UI may improve considerably. To enable Hardware Acceleration on an application, simply add the android:hardwareAccelerated tag to the manifest file.
After adding that tag to the application element, simply recompile and test your app. It is very important to fully test your app after you add this line. Although it’s unlikely that Hardware Acceleration will negatively affect your app, it is certainly possible. It is a good idea to make sure all of the views and animations still work as you expect it to.
If you find that certain screens seem to have problems with Hardware Acceleration, you can disable it on a per Activity basis if needed as well. To do so, simply add the tag (set to false) to the activity tag within the manifest. This allows you to enable Hardware Acceleration for the entire application while removing it for certain parts. And this also works in the reverse. You can enable only specific Activities while leaving it off for the majority of the application.
One other interesting feature in the IO Session (linked below) is the concept of a View Layer. By using this new Layer method, you are able to use the GPU within the device to speed up animations (IE ListView scrolling). Check out View.setLayerType for some more information.
For more details about Hardware Acceleration–and really some interesting information on how views are actually drawn in Android–check out this Google IO Session. And like most things Android-related, Google has a detailed page here on Hardware Acceleration.