Book Image

Building Android UIs with Custom Views

By : Raimon Ràfols Montane
Book Image

Building Android UIs with Custom Views

By: Raimon Ràfols Montane

Overview of this book

To build great user interfaces for your Android apps that go beyond the standard UI elements, you need to use custom Android views. With these, you can give your app a distinctive look and ensure that it functions properly across multiple devices. This book will help you construct a great UI for your apps by teaching you how to create custom Android views. You will start by creating your first Android custom view and go through the design considerations. You will then see how the right choices will enable your custom view to perform seamlessly across multiple platforms and Android versions. You will create custom styleable attributes that work with Android XML layouts, learn to process touch events, define custom attributes, and add properties and events to them. By the end of this book, you will be able to create apps with custom views that are responsive and adaptable to make your app distinctive and an instant hit with its users.
Table of Contents (12 chapters)

Advanced 2D Rendering

Being able to draw more complex primitives or use a composition of them is critical to making the user experience of our custom view awesome, useful, and special. So far, we've been using some drawing and rendering operations on our custom view, but if we check the Android documentation closely, that's a much reduced set of what Android provides to developers. We have drawn some primitives, saved and restored our canvas state, and applied some clipping operations, but that's only the top thin layer. In this chapter, we'll see these operations again, but we'll also see few new drawing operations and how we can use everything together. We'll cover the following topics in more detail:

  • Drawing operations
  • Masking and clipping
  • Gradients
  • Putting it all together