getContentResolver().query(TvContract.Channel.CONTENT_URI, 投影, null, null, null) 返回空 cursor

Question

I am trying to get all the available channels in TvProvider database (tv.db), with help of the below code. But the cursor is returning as empty.

val tvInputManager = getSystemService(TvInputManager::class.java)
tvInputManager.registerCallback(tvInputCallback, handler)

if (tvInputManager.tvInputList != null && tvInputManager.tvInputList.size > 0) {
    for (input in tvInputManager.tvInputList) {
        if (input != null && !input.isPassthroughInput) {
            val projection = arrayOf(
                TvContract.Channels._ID,
                TvContract.Channels.COLUMN_DISPLAY_NUMBER
            )
            var tvInputInfo = tvInputManager.getTvInputInfo(input.id)
            var uri = TvContractCompat.buildChannelsUriForInput(tvInputInfo?.id)
            val cursor = contentResolver.query(TvContract.Channels.CONTENT_URI, projection, null, null, null)
            Log.d("CHANNELS_DATA", "${TvContract.Channels.CONTENT_URI}")
            cursor?.moveToFirst()
            Log.d("CHANNELS_DATA", "${cursor?.count} CHANNELS FOUND")
        }
    }
}

Below are the permissions added in the Android Manifest file

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_TV_LISTINGS" />
<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" />
<uses-permission android:name="com.android.providers.tv.permission.ACCESS_WATCHED_PROGRAMS" />

Answer 1

You will get only own channels (channels added by your Tv Input Service). To be able to list all entries your app should have special ( signatureOrSystem ) permission: ACCESS_ALL_EPG_DATA . Please check docs: https://source.android.com/devices/tv#permissions_and_access_control