By Barry Burd

Television sets don’t have touch screens. So, how will your Android app function on the TV? When you start up the emulator and click your mouse on the TV screen’s icons, you find the emulator to be particularly unresponsive. Look for a small panel of buttons on the edge of the emulator window.

An Android TV emulator’s buttons.

An Android TV emulator’s buttons.

In this image, the capsule-shaped button and the left/right/up/down buttons surrounding that capsule do most of the work. Use these directional buttons to scroll from one screen item to another. Use the capsule-shaped button as a kind of Enter key.

If you look at the emulator’s Home screen, you might see an icon displaying the words Videos by Your Company.

The skeletal app’s icon.

The skeletal app’s icon.

When you click the Videos by Your Company icon, the emulator fires up the activity shown below.

The skeletal app’s main activity.

The skeletal app’s main activity.

The app’s layout has several rows. The top row has the heading Category Zero and has several Movie ABC entries. The next several rows don’t look like real rows. In fact, only one of the headings (Category Zero) appears immediately to the left of its corresponding items. The Category Two row heading appears roughly midway between the top and bottom of the screen, but the movie items in the Category Two row appear near the bottom of the screen.

This happens because the items are taller than the headings, and the layout tries to keep as many headings on the screen as possible. When the user scrolls from one heading to another (say, from Category Zero to Category Two), the rows of items scroll proportionately so that the Category Two heading is immediately to the left of its Category Two items.

Category Zero is highlighted. If you scroll rightward from Category Zero, you see a highlighted version of a video (the leftmost video in the Category Zero row).

You’ve scrolled to one of the videos.

You’ve scrolled to one of the videos.

If you press Enter with a video selected, you see a detail screen for that particular video.

A detail screen.

A detail screen.

None of the videos in the fictional app really exist, so the detailed description of each video is mumbo-jumbo. (According to Google Translate, the first few sentences are Latin for “Clinical this traffic. This cartoon always drink. Unfortunately, sad, clinical, but always the latest and the mass of Zen as it has been, it is not the earth, who Planning relax.” Does this sound like a movie that you’d want to rent or buy?)

The emulator’s Back button returns you to the grid full of videos. If you scroll downward, you eventually reach a list of preferences.

Some preferences.

Some preferences.

The richness of Android Studio’s skeletal TV app might seem strange. But there’s method to this madness. It’s all about the ten-foot experience, also known as the lean-back experience.

When you use a computer, you’re in work mode. You lean forward and try to accomplish something. (It might be something frivolous, but it’s an accomplishment nevertheless.) When you watch television, you’re not in work mode. You want to minimize any accomplishment phase. Your primary purpose is to lean back and enjoy the show. You want to relax.

So, with Android TV, it’s especially important that the user interface is unobtrusive. You want every interface to look like every other interface. That way, you can use simple reflexes to navigate from category to category, from movie to movie, and from a highlighted movie to details about the movie. If the skeletal app has so much pre-built scaffolding, it’s to make that scaffolding be the same for every app’s interface. With such a familiar interface, users can ignore the app’s interface and relax with their favorite movies.