Customize playback controls

Once you've decided how to organize your app content for navigating and browsing, consider whether you want a queue or any custom controls for playing the content.

Car makers and Google take care of implementing and styling the playback view, minimized control bar, and queue. They also provide a basic set of playback controls, including:

• Play/Pause
• Next (If supported by your app)
• Previous (If supported by your app)
• Overflow

However, if you want to customize the queue or provide additional playback actions, you need to decide:

• Whether to display thumbnails for queue items
• Whether to display an icon or elapsed time for the currently playing item in the queue
• Whether to include previously played items in the queue
• Which custom actions you want on the control bar, and whether they should replace the car makers' Next and Previous controls
• What the icons representing the relevant states of each action (such as available and disabled) will look like

Playback view examples

Playback control requirements

When designing playback controls, prioritize the following:

• Consistent app UI: App developers should make custom media playback controls in cars consistent with users' experiences on other apps and devices
• Readability: Text can appear smaller when paired with iconography, so text in icons should be maximized within the available space.

These requirements and recommendations will help you create effective controls.

Requirement level	Requirements
MUST	Provide monochrome vector icons for any custom actions you add, and change them dynamically to indicate state
SHOULD	If using text or numbers in an icon, use the maximum space in the bounding box to make the text as large and readable as possible
MAY	Provide up to 6 customactions (or up to 8, if not using Next and Previous)

Queue

You should also provide your user with a quick and easy way to browse the queue of upcoming media. The queue of upcoming media can include artists and thumbnails, as shown in the following examples.

Queue requirements

To help minimize distractions while driving, make sure users can see what's currently playing at a glance.

Requirement level	Requirements
SHOULD	Provide an indicator for the currently playing queue item Include previously played items in the queue To learn more about progress indicators and the queue, review Enable playback control.
MAY	Provide thumbnails for queue items