I received an email a few days ago, where I had a request for the Book Dash Android app to support “Switch Access”. To be honest, I had no idea what this email meant. My first thought was, “Hey, this will never run on a Nintendo Switch” but I realised that this probably wasn’t what they were requesting. After doing a bit more research on what exactly Switch Access is in Android, I realised there isn’t a lot of information around the Android Accessibility feature. Hopefully after reading through this blog post you will be interested in making sure your app is Switch Access compatible.
What is Accessibility?
Accessibility refers to the design of products, devices, services, or environments for people who experience disabilities (ref). For example, some people may be visually impaired and use a service like TalkBack on their device, which speaks out everything on their screen. Some people may enlarge the size of the font of their phone so they can read it clearly. Whilst others might suffer from muscle conditions that prevent them from being able to use the touch screen. This is where Switch Access is meant to help.
What is Android Switch Access?
Switch Access allows users with limited dexterity to use their Android device without using the touch screen. Users typically would use a device similar to the one pictured below to navigate the user interface of their phone.
Some switches have one button, others have two buttons or more. Switch Access can be configured to use a keyboard, a device like the one pictured above or built-in buttons on your device such as the volume up and volume down key.
Here is a video explaining how it works:
Great, we’ve now seen how it works, lets try use it on our app.
Enabling Switch Access for Testing
In order to test our apps with Switch Access, we need to enable it. In order to enable it you need to do the following:
- Open Settings on your device.
- Open the “Accessibility” section.
- There should be a service listed called “Switch Access”. Select this service. Before enabling the service, click on the “Settings” for the service. Click “Assign Switches for Scanning”. Here is where you will map certain key events to “Next” and “Select” action.
- Click “Select”, and then press the key you want to map to the “Select” function. I pressed the “Volume Down” button. Repeat this for the “Next” action, I used the “Volume Up” for the “Next” action but you can use any key you wish.
- Once you have done this, click back and enable “Switch Access”.
We can now navigate through our phone using the volume up and down buttons.
How do I make my app Switch Access compatible?
This is the part that was a mystery that I was battling to solve myself. No amount of Googling got me the result I was looking for, so hopefully my insights can help you achieve compatibility for your apps.
TL;DR: Make sure views that are clickable are selectable and reachable by a keyboard. Make sure views that require gestures can also be properly navigated to without using the required gesture.
Unfortunately there is no “enable this flag and switch access will work” solution to this problem. After using the Book Dash app with Switch Access enabled, I realised there were a few places that didn’t work well with the service enabled.
Switch Access problems in Book Dash
1. Inability to turn a page of the book
The screen that displays the book for reading is in a
ViewPager, which means users have to swipe to get to the next page. This was intuitive for me whilst using the touch screen, but not whilst using it with Switch Access. There was no way to turn the page of the book without swiping on the screen.
The solution for my ViewPager gesture scrolling, was to add click listeners onto each page of the book to go to the next and previous page of the book. I then added “focusable” fields onto the views that had click listeners attached. The following lines were added to each page container (with the click listeners pointing to the correct logic):
2. Two clickable areas on the download button
Another example in the Book Dash app was the Download Book button which had two clickable areas. Accessing it using Switch Access caused a bit of frustration, as a secondary dialog showed up asking which one to select.
The solution for this issue was to remove
android:clickable=“true” on the outer view, as the custom view already defined a clickable attribute. Simple fix, but saves users a lot of frustration!
If you want to see more code, check out the open source Github repository for more information.
Enabling Switch Access and testing your app with it on allows you to make your app accessible for users with limited dexterity. This is vitally important if you want to make a high quality, accessible app. In the next few posts we will be looking into other small improvements to make the app more accessible.
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