Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Building Android UIs with Custom Views
Building Android UIs with Custom Views

Building Android UIs with Custom Views: Build amazing custom user interfaces with Android custom views

Arrow left icon
Profile Icon Ràfols Montane
Arrow right icon
$19.99 per month
Paperback Oct 2017 294 pages 1st Edition
eBook
$27.98 $39.99
Paperback
$48.99
Subscription
Free Trial
Renews at $19.99p/m
Arrow left icon
Profile Icon Ràfols Montane
Arrow right icon
$19.99 per month
Paperback Oct 2017 294 pages 1st Edition
eBook
$27.98 $39.99
Paperback
$48.99
Subscription
Free Trial
Renews at $19.99p/m
eBook
$27.98 $39.99
Paperback
$48.99
Subscription
Free Trial
Renews at $19.99p/m

What do you get with a Packt Subscription?

Free for first 7 days. $19.99 p/m after that. Cancel any time!
Product feature icon Unlimited ad-free access to the largest independent learning library in tech. Access this title and thousands more!
Product feature icon 50+ new titles added per month, including many first-to-market concepts and exclusive early access to books as they are being written.
Product feature icon Innovative learning tools, including AI book assistants, code context explainers, and text-to-speech.
Product feature icon Thousands of reference materials covering every tech concept you need to stay up to date.
Subscribe now
View plans & pricing
Table of content icon View table of contents Preview book icon Preview Book

Building Android UIs with Custom Views

Implementing Your First Custom View

In the previous chapter, we've seen how to create the foundations of a custom view, but unless we add some more features and customizations it'll be pretty useless. In this chapter, we'll continue building on top of these foundations, see how we can parameterize our custom view to allow either ourselves or any other developer to customize them, and at the end, cover some rendering that will enable us to build slightly more complex custom views.

In addition, as we've mentioned in the previous chapter, we can create custom layouts as well. In this chapter, we'll see how to create a simple custom layout.

In more detail, we'll cover the following topics:

  • Measuring and parameterizing our custom view
  • Instantiating custom views
  • Creating custom layouts
  • Basic rendering

Measuring and parameterizing our custom view

In order to have a good reusable custom view, it needs to be able to adapt to different sizes and device resolutions, and to increase its reusability even more it should support parameterization.

Measuring our custom view

In the quick example we built in the previous chapter, we delegated all sizes and measurement to the parent view itself. To be honest, we haven't even delegated it; we just didn't do anything specifically to take care of that. Being able to control the size and dimensions of our custom view is something we definitely need to pay some attention to. To start, we're going to override the onMeasure() method from view as follows:

@Override 
protected...

Instantiating custom views

Now that we've seen how to set parameters on the XML layout and parse them on our custom view class, we'll see how to instantiate custom views from code as well and reuse then as much as possible from both instantiation mechanisms.

Instantiating custom views from code

On our custom view, we've created a single constructor with two parameters, a Context and an AttributeSet. Now, if we're creating our UI programmatically, or if by any other reason we need to instantiate our custom view by code, we need to create an additional constructor.

As we want to keep using our custom view in our XML layouts, we have to keep both constructors. To code avoid duplication, we will create some...

Creating a custom layout

Android provides several layouts to position our views in many different ways, but if these standard layouts aren't useful for our specific use case, we can create our own layouts.

Extending ViewGroup

The process to create a custom layout is quite similar to creating a custom view. We've got to create a class that extends from ViewGroup instead of view, create the appropriate constructors, implement the onMeasure() method, and override the onLayout() method rather than the onDraw() method.

Let's create a very simple custom layout; it will add elements to the right of the previous element until it doesn't fit on the screen, then it'll start a new row, using the higher element...

Basic rendering

So far we've only been drawing a solid background or a linear gradient. That's neither exciting nor really useful. Let's see how we can draw more interesting shapes and primitives. We'll do so by creating an example of a circular activity indicator that we'll be adding more and more features to in the following chapters.

Creating the basic circular activity indicator

The Canvas class provides us with many drawing functions; for example:

  • drawArc()
  • drawBitmap()
  • drawOval()
  • drawPath()

To draw a circular activity indicator, we can use the drawArc() method. Let's create the basic class and draw an arc:

public class CircularActivityIndicator extends View { 
    private static final...

Summary

In this chapter, we have seen how to measure and how to add parameters to our custom view. We also saw how to instantiate a custom view from code and use a Builder pattern to simplify all the parameters and keep our code cleaner. In addition, we went through a quick example of a custom layout and we started building a circular activity indicator. In the next chapter, we will see how to handle events and add some interactions to the circular activity indicator we've just started to build.

Left arrow icon Right arrow icon
Download code icon Download Code

Key benefits

  • Move beyond default UI templates, create and customize amazing UIs with Android Custom View
  • Enable smooth data flow and create futuristic UIs by creating flexible custom views
  • Scale your apps with responsive and data intensive views

Description

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.

Who is this book for?

This book is for Android developers who want to create great user interfaces and move beyond the basics of the standard UI elements. They must have basic Android development knowledge along with basic Java programming.

What you will learn

  • Extend the standard UI widget framework by creating Custom views
  • Add complex rendering, animations, and interactions to your views
  • Optimize performance and decrease battery usage
  • Implement custom views to share between multiple projects, or share it publicly
  • Create 3D custom views using OpenGL ES

Product Details

Country selected
Publication date, Length, Edition, Language, ISBN-13
Publication date : Oct 27, 2017
Length: 294 pages
Edition : 1st
Language : English
ISBN-13 : 9781785882869
Vendor :
Google
Category :
Languages :
Tools :

What do you get with a Packt Subscription?

Free for first 7 days. $19.99 p/m after that. Cancel any time!
Product feature icon Unlimited ad-free access to the largest independent learning library in tech. Access this title and thousands more!
Product feature icon 50+ new titles added per month, including many first-to-market concepts and exclusive early access to books as they are being written.
Product feature icon Innovative learning tools, including AI book assistants, code context explainers, and text-to-speech.
Product feature icon Thousands of reference materials covering every tech concept you need to stay up to date.
Subscribe now
View plans & pricing

Product Details

Publication date : Oct 27, 2017
Length: 294 pages
Edition : 1st
Language : English
ISBN-13 : 9781785882869
Vendor :
Google
Category :
Languages :
Tools :

Packt Subscriptions

See our plans and pricing
Modal Close icon
$19.99 billed monthly
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Simple pricing, no contract
$199.99 billed annually
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Choose a DRM-free eBook or Video every month to keep
Feature tick icon PLUS own as many other DRM-free eBooks or Videos as you like for just $5 each
Feature tick icon Exclusive print discounts
$279.99 billed in 18 months
Feature tick icon Unlimited access to Packt's library of 7,000+ practical books and videos
Feature tick icon Constantly refreshed with 50+ new titles a month
Feature tick icon Exclusive Early access to books as they're written
Feature tick icon Solve problems while you work with advanced search and reference features
Feature tick icon Offline reading on the mobile app
Feature tick icon Choose a DRM-free eBook or Video every month to keep
Feature tick icon PLUS own as many other DRM-free eBooks or Videos as you like for just $5 each
Feature tick icon Exclusive print discounts

Frequently bought together


Stars icon
Total $ 141.97
Expert Android Programming
$48.99
Hands-On Android UI Development
$43.99
Building Android UIs with Custom Views
$48.99
Total $ 141.97 Stars icon

Table of Contents

11 Chapters
Getting Started Chevron down icon Chevron up icon
Implementing Your First Custom View Chevron down icon Chevron up icon
Handling Events Chevron down icon Chevron up icon
Advanced 2D Rendering Chevron down icon Chevron up icon
Introducing 3D Custom Views Chevron down icon Chevron up icon
Animations Chevron down icon Chevron up icon
Performance Considerations Chevron down icon Chevron up icon
Sharing Our Custom View Chevron down icon Chevron up icon
Implementing Your Own EPG Chevron down icon Chevron up icon
Building a Charts Component Chevron down icon Chevron up icon
Creating a 3D Spinning Wheel Menu Chevron down icon Chevron up icon
Get free access to Packt library with over 7500+ books and video courses for 7 days!
Start Free Trial

FAQs

What is included in a Packt subscription? Chevron down icon Chevron up icon

A subscription provides you with full access to view all Packt and licnesed content online, this includes exclusive access to Early Access titles. Depending on the tier chosen you can also earn credits and discounts to use for owning content

How can I cancel my subscription? Chevron down icon Chevron up icon

To cancel your subscription with us simply go to the account page - found in the top right of the page or at https://subscription.packtpub.com/my-account/subscription - From here you will see the ‘cancel subscription’ button in the grey box with your subscription information in.

What are credits? Chevron down icon Chevron up icon

Credits can be earned from reading 40 section of any title within the payment cycle - a month starting from the day of subscription payment. You also earn a Credit every month if you subscribe to our annual or 18 month plans. Credits can be used to buy books DRM free, the same way that you would pay for a book. Your credits can be found in the subscription homepage - subscription.packtpub.com - clicking on ‘the my’ library dropdown and selecting ‘credits’.

What happens if an Early Access Course is cancelled? Chevron down icon Chevron up icon

Projects are rarely cancelled, but sometimes it's unavoidable. If an Early Access course is cancelled or excessively delayed, you can exchange your purchase for another course. For further details, please contact us here.

Where can I send feedback about an Early Access title? Chevron down icon Chevron up icon

If you have any feedback about the product you're reading, or Early Access in general, then please fill out a contact form here and we'll make sure the feedback gets to the right team. 

Can I download the code files for Early Access titles? Chevron down icon Chevron up icon

We try to ensure that all books in Early Access have code available to use, download, and fork on GitHub. This helps us be more agile in the development of the book, and helps keep the often changing code base of new versions and new technologies as up to date as possible. Unfortunately, however, there will be rare cases when it is not possible for us to have downloadable code samples available until publication.

When we publish the book, the code files will also be available to download from the Packt website.

How accurate is the publication date? Chevron down icon Chevron up icon

The publication date is as accurate as we can be at any point in the project. Unfortunately, delays can happen. Often those delays are out of our control, such as changes to the technology code base or delays in the tech release. We do our best to give you an accurate estimate of the publication date at any given time, and as more chapters are delivered, the more accurate the delivery date will become.

How will I know when new chapters are ready? Chevron down icon Chevron up icon

We'll let you know every time there has been an update to a course that you've bought in Early Access. You'll get an email to let you know there has been a new chapter, or a change to a previous chapter. The new chapters are automatically added to your account, so you can also check back there any time you're ready and download or read them online.

I am a Packt subscriber, do I get Early Access? Chevron down icon Chevron up icon

Yes, all Early Access content is fully available through your subscription. You will need to have a paid for or active trial subscription in order to access all titles.

How is Early Access delivered? Chevron down icon Chevron up icon

Early Access is currently only available as a PDF or through our online reader. As we make changes or add new chapters, the files in your Packt account will be updated so you can download them again or view them online immediately.

How do I buy Early Access content? Chevron down icon Chevron up icon

Early Access is a way of us getting our content to you quicker, but the method of buying the Early Access course is still the same. Just find the course you want to buy, go through the check-out steps, and you’ll get a confirmation email from us with information and a link to the relevant Early Access courses.

What is Early Access? Chevron down icon Chevron up icon

Keeping up to date with the latest technology is difficult; new versions, new frameworks, new techniques. This feature gives you a head-start to our content, as it's being created. With Early Access you'll receive each chapter as it's written, and get regular updates throughout the product's development, as well as the final course as soon as it's ready.We created Early Access as a means of giving you the information you need, as soon as it's available. As we go through the process of developing a course, 99% of it can be ready but we can't publish until that last 1% falls in to place. Early Access helps to unlock the potential of our content early, to help you start your learning when you need it most. You not only get access to every chapter as it's delivered, edited, and updated, but you'll also get the finalized, DRM-free product to download in any format you want when it's published. As a member of Packt, you'll also be eligible for our exclusive offers, including a free course every day, and discounts on new and popular titles.