Android Application Development Cookbook - Second Edition

Lights, Action, and Sound – getting the user's attention!

Most of the recipes in this chapter use the Notification object to alert your users, so this recipe will show an alternative approach for when you don't actually need a notification.

As the recipe title implies, we're going to use lights, action, and sound:

• Lights: Normally, you'd use the LED device, but that is only available through the Notification object, which we'll demonstrate later in the chapter. Instead we'll take this opportunity to use setTorchMode() (added in API 23—Android 6.0), to use the camera flash as a flashlight. (Note: as you'll see in the code, this feature will only work on an Android 6.0 device with a camera flash.)
• Action: We'll vibrate the phone.
• Sound: We'll use the ...