Main entry point for the Cast APIs. This class provides APIs and interfaces to access Google Cast devices.

To use the service, construct a GoogleApiClient.Builder and pass API to GoogleApiClient.Builder.addApi(Api ). Once you have your GoogleApiClient, call GoogleApiClient.connect() and wait for the GoogleApiClient.ConnectionCallbacks#onConnected method to be called.

Device discovery on Android is performed using the Android MediaRouter APIs that debuted in Jellybean MR2 (API level 18). The MediaRouter APIs are implemented in the Android v7 Support Library. These APIs provide a simple mechanism for discovering media destinations, such as Chromecasts, bluetooth speakers, Android-powered smart TVs, and other media playback devices; and for routing media content to and controlling playback on those endpoints. These endpoints are referred to as “media routes.”

1. The first step to using these APIs is to acquire the MediaRouter singleton. It is important for the application to hold on to the reference to this singleton for as long as the application will be using the MediaRouter APIs; otherwise it may get garbage collected at an inopportune time.
2. Next, an appropriate route selector must be constructed. The purpose of the route selector is to filter the routes down to only those that the application is interested in such as Cast devices. It is also possible to filter the routes further by supported receiver application, in the (typical) case where the sender application expects to use a specific one.
3. Third, a MediaRouter callback is constructed. This callback has methods that will be called by the MediaRouter whenever a route becomes available or unavailable or a route is selected by the user.