onDraw()method significantly reduces performance and can make your UI appear sluggish.
Custom Drawing | Android Developers - 1 views
Creating objects ahead of time is an important optimization. Views are redrawn very frequently, and many drawing objects require expensive initialization. Creating drawing objects within your
If your view doesn't need special control over its size, you only need to override one method:
Getting Started | Android Developers - 0 views
Welcome to Training for Android developers. Here you'll find sets of lessons within classes that describe how to accomplish a specific task with code samples you can re-use in your app. Classes are organized into several groups you can see at the top-level of the left navigation.
This first group, Getting Started, teaches you the bare essentials for Android app development. If you're a new Android app developer, you should complete each of these classes in order: