Media3 Cast Integration
Android (Google)OfficialCreated by Google LLCDistributed by Android (Google)
- Skill
- Tool integration
- Software development
- Apache-2.0
- No issues found
AutoGineer summary
Written by AutoGineer from the skill’s own files, not by the author
This skill provides a comprehensive guide for implementing Google Cast support in Android apps using the Jetpack Media3 library. It covers the necessary build configuration, manifest updates, and player initialization required to enable seamless casting. The guide also details how to manage playback state between local and remote devices, supports both Compose and View-based UI architectures, and provides a structured approach for migrating from the legacy Google Cast SDK to the modern Media3 implementation.
What it does
- Configures build dependencies for Jetpack Media3 Cast integration.
- Updates Android manifest files with required Cast options providers.
- Initializes CastPlayer and RemoteCastPlayer for unified playback control.
- Provides patterns for managing playback state transitions between local and remote devices.
- Offers guidance for implementing Cast UI components in both Jetpack Compose and legacy View systems.
- Outlines a safe migration path from the legacy Google Cast SDK to Media3.
When to use it
- When adding new Google Cast functionality to an Android application.
- When migrating an existing application from the legacy Google Cast SDK to Jetpack Media3.
- When building media playback services that require switching between local and remote Cast-enabled devices.
Advantages
- Uses modern Jetpack Media3 APIs for consistent media playback management.
- Simplifies the transition between local and remote playback states.
- Provides clear architectural patterns for both Compose and View-based UIs.
- Reduces complexity by replacing legacy forwarding player wrappers.
Usage examples
- “How do I add Google Cast support to my Android app using Media3?”
- The agent provides the necessary Gradle dependencies, manifest configuration steps, and instructions for initializing the CastPlayer within a MediaSessionService.
- “How can I migrate my existing Cast implementation to Media3?”
- The agent outlines a step-by-step migration process, including adding Media3 dependencies, updating the manifest, and eventually removing legacy Cast SDK components.
- “How do I implement a MediaRouteButton in Jetpack Compose?”
- The agent provides the implementation details for the MediaRouteButton composable and explains how to sync UI state with the active player's device information.
Install
Download the skill as a ZIP:
https://mp-staging.autogineer.com/agent-skills/android/media3-cast-integration/downloadUnzip it into the cross-client skills folder of your project:
mkdir -p .agents/skills && unzip media3-cast-integration.zip -d .agents/skills
Documentation by Google LLC
Prerequisites
Jetpack Media3 version must be
>= 1.9.0. Cast isn't available in lower versions.
Glossary
CastPlayer: Media3Playerthat controls playback on both local and remote Cast devices.RemoteCastPlayer: Media3Playerthat communicates with a Cast receiver, only used for remote playback.Google Cast SDK: Legacy casting SDK in maintenance mode, superseded by Jetpack Media3.
OptionsProvider: Interface providing configuration options to initialize GMSCastContext.
Common guidelines
Legacy Google Cast SDK is in maintenance mode.
For new Cast setups:
You must use Jetpack Media3 Cast.
You mustn't use legacy Cast SDK unless explicitly requested.
Step 1: Set up dependencies
To complete this step, you MUST ensure the following:
In the app-level build file, declare the
media3-castdependency version 1.9.0 or higher.implementation("androidx.media3:media3-cast:1.11.1")Ensure required Media3 dependencies are present:
androidx.media3:media3-exoplayerandroidx.media3:media3-sessionandroidx.media3:media3-ui-compose
If the application uses legacy Views, add
media3-ui.Enforce the same versions across all Media3 dependencies.
Use configurations in "Add build dependencies" section of Getting started with CastPlayer as the source of truth.
For apps without an existing Cast integration:
Verify legacy Cast SDK (
libs.play.services.cast.framework) is absent.
If Migrating from Legacy Cast SDK:
Add Media3 Cast dependencies first.
Keep existing legacy dependencies untouched at this stage to prevent compilation errors.
Step 2: Update the manifest
To complete this step, you MUST ensure the following:
Inside the manifest's
<application>tag, declare the Cast options provider.Use
DefaultCastOptionsProviderby default. See the "OptionsProvider" section in Getting started with CastPlayer.Declare a custom
OptionsProvideronly if explicitly requested. See Customize CastOptions.Ensure
INTERNETpermission is present. Don't add any unnecessary permissions.If Migrating from Legacy Cast SDK:
Don't delete existing custom options provider files or manifest entries.
Step 3: Implement the player and service
Architecture baseline
Before integrating Media3 Cast, an existing app follows one of two setups:
Local-only playback: Uses Media3
ExoPlayeronly to support local playback.Legacy Cast setup: Uses
ExoPlayerfor local playback, alongside aPlayerwrapper over the legacyRemoteMediaClientfor remote playback. The UI interfaces with aMediaSessioninteracting with aForwardingPlayer, which finally routes controls to either local or remote playback.
To complete this step, you MUST ensure the following:
Inside the application's
MediaSessionService(orMediaLibraryService)onCreate()method, initializeExoPlayerandCastPlayer.Use
CastPlayerby default unlessRemoteCastPlayeris explicitly requested. See the "Build a CastPlayer" section in Getting started with CastPlayer.For
CastPlayer, pass the instance directly toMediaSession.Builder.Replace all legacy forwarding player wrappers.
Don't delete legacy class files yet to prevent compilation errors during migration.
Advanced: RemoteCastPlayer
Use
RemoteCastPlayeronly if explicitly requested by user.Initialize
MediaSessionwithlocalPlayerand set aSessionAvailabilityListeneronRemoteCastPlayerto transfer playback state on Cast session availability changes:class PlaybackService : MediaSessionService() { private var mediaSession: MediaSession? = null private lateinit var localPlayer: ExoPlayer private lateinit var remotePlayer: RemoteCastPlayer override fun onCreate() { super.onCreate() localPlayer = ExoPlayer.Builder(this).build() remotePlayer = RemoteCastPlayer.Builder(this).build() mediaSession = MediaSession.Builder(this, localPlayer).build() remotePlayer.setSessionAvailabilityListener( object : SessionAvailabilityListener { override fun onCastSessionAvailable() { transferPlaybackState(localPlayer, remotePlayer) } override fun onCastSessionUnavailable() { transferPlaybackState(remotePlayer, localPlayer) } } ) } private fun transferPlaybackState(previousPlayer: Player, newPlayer: Player) { if (previousPlayer.mediaItemCount > 0) { val transferStateBuilder = PlayerTransferState.builderFromPlayer(previousPlayer) if (previousPlayer.playbackState == Player.STATE_ENDED || previousPlayer.currentPosition == C.TIME_END_OF_SOURCE) { transferStateBuilder.setCurrentMediaItemIndex(0) transferStateBuilder.setCurrentPosition(0) } transferStateBuilder.build().setToPlayer(newPlayer) } previousPlayer.stop() previousPlayer.clearMediaItems() newPlayer.prepare() mediaSession?.setPlayer(newPlayer) } }
Step 4: Set up the UI
Compose-based UI
To complete this step, you MUST ensure the following:
See the "Add a MediaRouteButton Composable to the Player" section in Getting started with CastPlayer for Compose integration guidelines.
Use the
MediaRouteButtoncomposable fromandroidx.media3.castpackage.Don't use
AndroidViewin the Compose UI hierarchy.Place
MediaRouteButtonin an area next to playback controls. Don't hide it behind system UI.Don't use
PlayerSurfacefor custom player UI. Use the Material3Playercomposable.Force recomposition on playback location shifts to ensure UI sync. Use key constraints on
DeviceInfochanges:@OptIn(UnstableApi::class) @Composable fun MainScreen() { val player = rememberMediaController() val deviceInfo = rememberDeviceInfo(player) player?.let { activePlayer -> key(deviceInfo) { PlayerScreen(player = activePlayer) } } } @Composable private fun rememberMediaController(): Player? { // Logic to connect MediaController to MediaSession and release it } @Composable private fun rememberDeviceInfo(player: Player?): DeviceInfo? { var deviceInfo by remember(player) { mutableStateOf(player?.deviceInfo) } DisposableEffect(player) { val activePlayer = player ?: return@DisposableEffect onDispose {} deviceInfo = activePlayer.deviceInfo val listener = object : Player.Listener { override fun onDeviceInfoChanged(info: DeviceInfo) { deviceInfo = info } } activePlayer.addListener(listener) onDispose { activePlayer.removeListener(listener) } } return deviceInfo }
View-based UI
To complete this step, you MUST ensure the following:
For View-based UI setups, see the "Add UI elements" section in Getting started with CastPlayer.
Casting Activities must extend
AppCompatActivityorFragmentActivityand use aTheme.AppCompatdescendant.Ensure the
AppCompattheme has a visibleActionBarif addingMediaRouteButtonto the options menu.Replace all instances and imports of
CastButtonFactorywithMediaRouteButtonFactory.Rebind
PlayerView.playerreferences upononDeviceInfoChangedevents to prevent black screens or UI freezes:private val playerListener: Player.Listener = object : Player.Listener { override fun onDeviceInfoChanged(deviceInfo: DeviceInfo) { // Resetting to null bypasses PlayerView.setPlayer()'s instance equality check // (this.player == player), forcing it to re-bind the video surface to the controller. playerView.player = null playerView.player = controller } }Migration to Compose:
Don't use
AndroidViewto wrap the legacyPlayerView.Implement Material3
Playercomposable andMediaRouteButtoncomposable as per Getting started with CastPlayer.Remove legacy XML layout declarations, menu files, and View component references.
Step 5: Clean up legacy Cast SDK code
[!WARNING] Warning: Don't perform cleanup directly. Remove legacy files and dependencies only when explicitly requested by the user.
To complete this step, you MUST ensure the following:
Remove legacy GMS Cast SDK (
libs.play.services.cast.framework) and MediaRouter (libs.androidx.mediarouter) dependencies.Delete custom
OptionsProviderclasses and manifest entries ifDefaultCastOptionsProvideris adopted.Remove legacy
MediaTransferReceivermanifest declarations if present.Remove all references to legacy Cast SDK components such as legacy helper wrappers, forwarding players, and
RemoteMediaClientinterfaces.Delete legacy View XML layouts, menu files, and references to
PlayerViewif the migration to Compose is complete.
Files
- ATTRIBUTION.mdAdded by AutoGineer978 B
- LICENSELicence file added by AutoGineer11.1 KiB
- SKILL.md10.5 KiB
- references/android/media/media3/cast/create-castplayer.md14.0 KiB
- references/android/media/media3/cast/customize-castoptions.md2.9 KiB
- references/android/media/media3/cast/index.md1.3 KiB
LICENSE
Apache License
Version 2.0, January 2004
http://www.apache.org/licenses/
TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
1. Definitions.
"License" shall mean the terms and conditions for use, reproduction,
and distribution as defined by Sections 1 through 9 of this document.
"Licensor" shall mean the copyright owner or entity authorized by
the copyright owner that is granting the License.
"Legal Entity" shall mean the union of the acting entity and all
other entities that control, are controlled by, or are under common
control with that entity. For the purposes of this definition,
"control" means (i) the power, direct or indirect, to cause the
direction or management of such entity, whether by contract or
otherwise, or (ii) ownership of fifty percent (50%) or more of the
outstanding shares, or (iii) beneficial ownership of such entity.
"You" (or "Your") shall mean an individual or Legal Entity
exercising permissions granted by this License.
"Source" form shall mean the preferred form for making modifications,
including but not limited to software source code, documentation
source, and configuration files.
"Object" form shall mean any form resulting from mechanical
transformation or translation of a Source form, including but
not limited to compiled object code, generated documentation,
and conversions to other media types.
"Work" shall mean the work of authorship, whether in Source or
Object form, made available under the License, as indicated by a
copyright notice that is included in or attached to the work
(an example is provided in the Appendix below).
"Derivative Works" shall mean any work, whether in Source or Object
form, that is based on (or derived from) the Work and for which the
editorial revisions, annotations, elaborations, or other modifications
represent, as a whole, an original work of authorship. For the purposes
of this License, Derivative Works shall not include works that remain
separable from, or merely link (or bind by name) to the interfaces of,
the Work and Derivative Works thereof.
"Contribution" shall mean any work of authorship, including
the original version of the Work and any modifications or additions
to that Work or Derivative Works thereof, that is intentionally
submitted to Licensor for inclusion in the Work by the copyright owner
or by an individual or Legal Entity authorized to submit on behalf of
the copyright owner. For the purposes of this definition, "submitted"
means any form of electronic, verbal, or written communication sent
to the Licensor or its representatives, including but not limited to
communication on electronic mailing lists, source code control systems,
and issue tracking systems that are managed by, or on behalf of, the
Licensor for the purpose of discussing and improving the Work, but
excluding communication that is conspicuously marked or otherwise
designated in writing by the copyright owner as "Not a Contribution."
"Contributor" shall mean Licensor and any individual or Legal Entity
on behalf of whom a Contribution has been received by Licensor and
subsequently incorporated within the Work.
2. Grant of Copyright License. Subject to the terms and conditions of
this License, each Contributor hereby grants to You a perpetual,
worldwide, non-exclusive, no-charge, royalty-free, irrevocable
copyright license to reproduce, prepare Derivative Works of,
publicly display, publicly perform, sublicense, and distribute the
Work and such Derivative Works in Source or Object form.
3. Grant of Patent License. Subject to the terms and conditions of
this License, each Contributor hereby grants to You a perpetual,
worldwide, non-exclusive, no-charge, royalty-free, irrevocable
(except as stated in this section) patent license to make, have made,
use, offer to sell, sell, import, and otherwise transfer the Work,
where such license applies only to those patent claims licensable
by such Contributor that are necessarily infringed by their
Contribution(s) alone or by combination of their Contribution(s)
with the Work to which such Contribution(s) was submitted. If You
institute patent litigation against any entity (including a
cross-claim or counterclaim in a lawsuit) alleging that the Work
or a Contribution incorporated within the Work constitutes direct
or contributory patent infringement, then any patent licenses
granted to You under this License for that Work shall terminate
as of the date such litigation is filed.
4. Redistribution. You may reproduce and distribute copies of the
Work or Derivative Works thereof in any medium, with or without
modifications, and in Source or Object form, provided that You
meet the following conditions:
(a) You must give any other recipients of the Work or
Derivative Works a copy of this License; and
(b) You must cause any modified files to carry prominent notices
stating that You changed the files; and
(c) You must retain, in the Source form of any Derivative Works
that You distribute, all copyright, patent, trademark, and
attribution notices from the Source form of the Work,
excluding those notices that do not pertain to any part of
the Derivative Works; and
(d) If the Work includes a "NOTICE" text file as part of its
distribution, then any Derivative Works that You distribute must
include a readable copy of the attribution notices contained
within such NOTICE file, excluding those notices that do not
pertain to any part of the Derivative Works, in at least one
of the following places: within a NOTICE text file distributed
as part of the Derivative Works; within the Source form or
documentation, if provided along with the Derivative Works; or,
within a display generated by the Derivative Works, if and
wherever such third-party notices normally appear. The contents
of the NOTICE file are for informational purposes only and
do not modify the License. You may add Your own attribution
notices within Derivative Works that You distribute, alongside
or as an addendum to the NOTICE text from the Work, provided
that such additional attribution notices cannot be construed
as modifying the License.
You may add Your own copyright statement to Your modifications and
may provide additional or different license terms and conditions
for use, reproduction, or distribution of Your modifications, or
for any such Derivative Works as a whole, provided Your use,
reproduction, and distribution of the Work otherwise complies with
the conditions stated in this License.
5. Submission of Contributions. Unless You explicitly state otherwise,
any Contribution intentionally submitted for inclusion in the Work
by You to the Licensor shall be under the terms and conditions of
this License, without any additional terms or conditions.
Notwithstanding the above, nothing herein shall supersede or modify
the terms of any separate license agreement you may have executed
with Licensor regarding such Contributions.
6. Trademarks. This License does not grant permission to use the trade
names, trademarks, service marks, or product names of the Licensor,
except as required for reasonable and customary use in describing the
origin of the Work and reproducing the content of the NOTICE file.
7. Disclaimer of Warranty. Unless required by applicable law or
agreed to in writing, Licensor provides the Work (and each
Contributor provides its Contributions) on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
implied, including, without limitation, any warranties or conditions
of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
PARTICULAR PURPOSE. You are solely responsible for determining the
appropriateness of using or redistributing the Work and assume any
risks associated with Your exercise of permissions under this License.
8. Limitation of Liability. In no event and under no legal theory,
whether in tort (including negligence), contract, or otherwise,
unless required by applicable law (such as deliberate and grossly
negligent acts) or agreed to in writing, shall any Contributor be
liable to You for damages, including any direct, indirect, special,
incidental, or consequential damages of any character arising as a
result of this License or out of the use or inability to use the
Work (including but not limited to damages for loss of goodwill,
work stoppage, computer failure or malfunction, or any and all
other commercial damages or losses), even if such Contributor
has been advised of the possibility of such damages.
9. Accepting Warranty or Additional Liability. While redistributing
the Work or Derivative Works thereof, You may choose to offer,
and charge a fee for, acceptance of support, warranty, indemnity,
or other liability obligations and/or rights consistent with this
License. However, in accepting such obligations, You may act only
on Your own behalf and on Your sole responsibility, not on behalf
of any other Contributor, and only if You agree to indemnify,
defend, and hold each Contributor harmless for any liability
incurred by, or claims asserted against, such Contributor by reason
of your accepting any such warranty or additional liability.
END OF TERMS AND CONDITIONS
APPENDIX: How to apply the Apache License to your work.
To apply the Apache License to your work, attach the following
boilerplate notice, with the fields enclosed by brackets "[]"
replaced with your own identifying information. (Don't include
the brackets!) The text should be enclosed in the appropriate
comment syntax for the file format. We also recommend that a
file or class name and description of purpose be included on the
same "printed page" as the copyright notice for easier
identification within third-party archives.
Copyright [yyyy] [name of copyright owner]
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.Requirements and compatibility
Works with: Claude Code, Claude apps, OpenAI Codex, GitHub Copilot, Cursor, Gemini CLI, Kiro, OpenCode, Goose, Amp, Roo Code, JetBrains Junie, Factory Droid, Devin (ex-Windsurf), Mistral Vibe, OpenHands, Letta
“Works with” means the tool reads the open Agent Skills format; a skill written for one tool may use features others lack.
Security
No issues found by our static scan· No issues found
A static scan is not a guarantee. Skills are third-party content: review a skill before you let an agent use it.
Attribution and licence
- Created by
- Google LLC
- Publisher
- Android (Google) (Official)
- Distributed by
- Android (Google)
- Source
- android/skills · media/media3-cast-integration · commit bf68e2d
- Licence
- Apache License 2.0 (redistribution allowed)
- LICENSE (added by AutoGineer from LICENSE.txt)
- ATTRIBUTION.md (written by AutoGineer)
- Synced
AutoGineer is not affiliated with or endorsed by Google LLC or Android (Google).
Download ZIP
The ZIP holds the skill’s files, its licence files and an ATTRIBUTION.md. Download media3-cast-integration.zip