Android Tv: get list of channels

问题:

I've installed the androidtv-sample-inputs so I can fake some Tv inputs and have some channels and I wanted to get information about that channels, however, when I query to get that information I get an empty cursors.

What i've tried so far is:

TvInputManager tv = (TvInputManager)getApplicationContext().getSystemService(Context.TV_INPUT_SERVICE);

    List<TvInputInfo> list = tv.getTvInputList();

    String[] projection =  {
            TvContract.Channels._ID,
            TvContract.Channels.COLUMN_DISPLAY_NUMBER
    };

    ContentResolver cr = getContentResolver();

    Iterator<TvInputInfo> it = list.iterator();
    while(it.hasNext()) {
        TvInputInfo aux = it.next();
        Uri uri = TvContract.buildChannelsUriForInput(aux.getId());

        Log.d("TAG", uri.toString());
        Log.d("TAG", aux.toString());

        Cursor cur = cr.query(uri, projection, null, null ,null);
        Log.d("TAG", cur.toString());

        if(cur.moveToFirst()) {
            Log.d("TAG", "not empty cursors");
        }

    }

I have already added the uses-permission and I've checked that the tv input are not pass-through.

<uses-permission android:name="com.android.providers.tv.permission.READ_EPG_DATA" />
<uses-permission android:name="com.android.providers.tv.permission.WRITE_EPG_DATA" />
<uses-permission android:name="com.android.providers.tv.permission.ACCESS_ALL_EPG_DATA"/>

回答1:

What kind of permission are you using ?

If your application isn't systemOrSignature, you can only access your own channels and programs from queries to the TV provider. All the queries you're doing are filtered on your package name.

I guess that the information you can retrieve from a channel are restricted to what is accessible from TvInputInfo.

回答2:

Additionally to "com.android.providers.tv.xxx" EPG permissions needed in the manifest file, you must sign your .apk ! Otherwise you will see all the TvInput available on your device but none of the channels composing these tvInput (and this, without any error returned ;-)). Android Studio provides this features ('BUILD' menu entry then 'Generate Signed APK') see How to sign an android apk file