added in version 1.0.0
belongs to Maven artifact androidx.tvprovider:tvprovider:1.0.0-beta01

PreviewChannelHelper

public class PreviewChannelHelper
extends Object

java.lang.Object
   ↳ androidx.tvprovider.media.tv.PreviewChannelHelper


From a user's perspective, the TV home screen has two types of channels: the single Live Channels row versus the App preview Channels. This class is concerned with App Channels; or more precisely: your app's preview Channels. In API 26+, all TV apps are allowed to create multiple channels and publish those Channels to the home screen.

This class provides convenience methods to help you publish, update and delete channels; add, update or remove programs in a channel. You do not need to know anything about Content Providers, Content Resolvers, Cursors or such to publish your channels. This class abstracts away all database interactions for you.

To make it easy for you to distinguish classes that help you build App Channels, the support library uses the prefix Preview- to denote the classes that pertain to app Channels. Hence, the classes PreviewChannel and PreviewProgram help your app add channels to the TV home page. All calls to methods in the class should be made on worker threads.

Summary

Public constructors

PreviewChannelHelper(Context context)
PreviewChannelHelper(Context context, int urlConnectionTimeoutMillis, int urlReadTimeoutMillis)

Public methods

void deletePreviewChannel(long channelId)

Removes a preview channel from the system's content provider (aka TvProvider).

void deletePreviewProgram(long programId)

Removes programs from a preview channel.

List<PreviewChannel> getAllChannels()

The TvProvider does not allow select queries.

PreviewChannel getPreviewChannel(long channelId)

Retrieves a single preview channel from the TvProvider.

PreviewProgram getPreviewProgram(long programId)

Retrieves a single preview program from the system content provider (aka TvProvider).

WatchNextProgram getWatchNextProgram(long programId)

Retrieves a single WatchNext program from the system content provider (aka TvProvider).

long publishChannel(PreviewChannel channel)

Publishing a channel to the TV home screen is a two step process: first, you add the channel to the TV content provider; second, you make the channel browsable (i.e.

long publishDefaultChannel(PreviewChannel channel)

This is a convenience method that simply publishes your first channel for you.

long publishPreviewProgram(PreviewProgram program)

Adds programs to a preview channel.

long publishWatchNextProgram(WatchNextProgram program)

Adds a program to the Watch Next channel

void updatePreviewChannel(long channelId, PreviewChannel update)

To update a preview channel, you need to use the PreviewChannel.Builder to set the attributes you wish to change.

void updatePreviewProgram(long programId, PreviewProgram update)

Updates programs in a preview channel.

void updateWatchNextProgram(WatchNextProgram upgrade, long programId)

Updates a WatchNext program.

Protected methods

Bitmap downloadBitmap(Uri logoUri)

Downloads a Bitmap from a remote server.

Inherited methods

Public constructors

PreviewChannelHelper

added in version 1.0.0
public PreviewChannelHelper (Context context)

Parameters
context Context

PreviewChannelHelper

added in version 1.0.0
public PreviewChannelHelper (Context context, 
                int urlConnectionTimeoutMillis, 
                int urlReadTimeoutMillis)

Parameters
context Context

urlConnectionTimeoutMillis int: see URLConnection.setConnectTimeout(int)

urlReadTimeoutMillis int: see URLConnection.setReadTimeout(int)

Public methods

deletePreviewChannel

added in version 1.0.0
public void deletePreviewChannel (long channelId)

Removes a preview channel from the system's content provider (aka TvProvider).

Parameters
channelId long

deletePreviewProgram

added in version 1.0.0
public void deletePreviewProgram (long programId)

Removes programs from a preview channel.

Parameters
programId long

getAllChannels

added in version 1.0.0
public List<PreviewChannel> getAllChannels ()

The TvProvider does not allow select queries. Hence, unless you are querying for a single PreviewChannel by id, you must get all of your channels at once and then use the returned list as necessary.

Returns
List<PreviewChannel>

getPreviewChannel

added in version 1.0.0
public PreviewChannel getPreviewChannel (long channelId)

Retrieves a single preview channel from the TvProvider. When you publish a preview channel, the TvProvider assigns an ID to it. That's the channelId to use here.

Parameters
channelId long: ID of preview channel in TvProvider

Returns
PreviewChannel PreviewChannel or null if not found

getPreviewProgram

added in version 1.0.0
public PreviewProgram getPreviewProgram (long programId)

Retrieves a single preview program from the system content provider (aka TvProvider).

Parameters
programId long

Returns
PreviewProgram

getWatchNextProgram

added in version 1.0.0
public WatchNextProgram getWatchNextProgram (long programId)

Retrieves a single WatchNext program from the system content provider (aka TvProvider).

Parameters
programId long

Returns
WatchNextProgram

publishChannel

added in version 1.0.0
public long publishChannel (PreviewChannel channel)

Publishing a channel to the TV home screen is a two step process: first, you add the channel to the TV content provider; second, you make the channel browsable (i.e. visible). This method adds the channel to the TV content provider for you and returns a channelId. Next you must use the channelId to make the channel browsable.
There are two ways you can make a channel browsable:
a) For your first channel, simply ask the system to make the channel browsable: TvContractCompat.requestChannelBrowsable(context,channelId)
b) For any additional channel beyond the first channel, you must get permission from the user. So if this channel is not your first channel, you must request user permission through the following intent. So take the channelId returned by this method and do the following inside an Activity or Fragment:

 intent = new Intent(TvContractCompat.ACTION_REQUEST_CHANNEL_BROWSABLE);
 intent.putExtra(TvContractCompat.EXTRA_CHANNEL_ID, channelId);
 startActivityForResult(intent, REQUEST_CHANNEL_BROWSABLE);
 

Creating a PreviewChannel, you may pass to the builder a url as your logo. In such case, updatePreviewChannel(long, PreviewChannel) will load the logo over the network. To use your own networking code, override downloadBitmap(Uri).

Parameters
channel PreviewChannel

Returns
long channelId or -1 if insertion fails. This is the id the system assigns to your published channel. You can use it later to get a reference to this published PreviewChannel.

Throws
IOException

publishDefaultChannel

added in version 1.0.0
public long publishDefaultChannel (PreviewChannel channel)

This is a convenience method that simply publishes your first channel for you. After calling publishChannel(PreviewChannel) to add the channel to the TvProvider, it calls TvContractCompat.requestChannelBrowsable(Context, long) to make the channel visible.

Only use this method to publish your first channel as you do not need user permission to make your first channel browsable (i.e. visible on home screen). For additional channels, see the documentations for publishChannel(PreviewChannel).

Creating a PreviewChannel, you may pass to the builder a url as your logo. In such case, updatePreviewChannel(long, PreviewChannel) will load the logo over the network. To use your own networking code, override downloadBitmap(Uri).

Parameters
channel PreviewChannel

Returns
long channelId: This is the id the system assigns to your published channel. You can use it later to get a reference to this published PreviewChannel.

Throws
IOException

publishPreviewProgram

added in version 1.0.0
public long publishPreviewProgram (PreviewProgram program)

Adds programs to a preview channel.

Parameters
program PreviewProgram

Returns
long

publishWatchNextProgram

added in version 1.0.0
public long publishWatchNextProgram (WatchNextProgram program)

Adds a program to the Watch Next channel

Parameters
program WatchNextProgram

Returns
long

updatePreviewChannel

added in version 1.0.0
public void updatePreviewChannel (long channelId, 
                PreviewChannel update)

To update a preview channel, you need to use the PreviewChannel.Builder to set the attributes you wish to change. Then simply pass in the built channel and the channelId of the preview channel. (The channelId is the ID you received when you originally published the preview channel.)

Creating a PreviewChannel, you may pass to the builder a url as your logo. In such case, updatePreviewChannel(long, PreviewChannel) will load the logo over the network. To use your own networking code, override downloadBitmap(Uri).

Parameters
channelId long

update PreviewChannel

Throws
IOException

updatePreviewProgram

added in version 1.0.0
public void updatePreviewProgram (long programId, 
                PreviewProgram update)

Updates programs in a preview channel.

Parameters
programId long

update PreviewProgram

updateWatchNextProgram

added in version 1.0.0
public void updateWatchNextProgram (WatchNextProgram upgrade, 
                long programId)

Updates a WatchNext program.

Parameters
upgrade WatchNextProgram

programId long

Protected methods

downloadBitmap

added in version 1.0.0
protected Bitmap downloadBitmap (Uri logoUri)

Downloads a Bitmap from a remote server. It is declared protected to allow you to override it to use your own networking implementation if you so wish.

Parameters
logoUri Uri

Returns
Bitmap

Throws
IOException