Basic behavior on the background mode

For now I can't get properly the Stream with the data, but with
a hardcoded url it works.

app/src/main/java/com/github/libretube/VideoOptionsDialog.kt

@@ -4,14 +4,39 @@ import android.app.Dialog
 import android.os.Bundle
 import android.widget.ArrayAdapter
 import androidx.fragment.app.DialogFragment
+import androidx.lifecycle.lifecycleScope
+import com.github.libretube.obj.Streams
+import com.google.android.exoplayer2.ExoPlayer
+import com.google.android.exoplayer2.MediaItem
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
 
-class VideoOptionsDialog : DialogFragment() {
+/**
+ * Dialog with different options for a selected video.
+ *
+ * @param videoId The video id.
+ */
+class VideoOptionsDialog(private val videoId: String) : DialogFragment() {
     /**
-     * List that stores the different menu options.
+     * List that stores the different menu options. In the future could be add more options here.
      */
-    private val list = arrayListOf("Background mode")
+    private val list = listOf("Background mode")
 
+    /**
+     * The response that gets when called the Api.
+     */
+    private lateinit var response: Streams
+
+    /**
+     * The [ExoPlayer] player. Followed tutorial [here](https://developer.android.com/codelabs/exoplayer-intro)
+     */
+    private var player: ExoPlayer? = null
+    private var playWhenReady = true
+    private var currentItem = 0
+    private var playbackPosition = 0L
+
+    /**
+     * Dialog that returns a [MaterialAlertDialogBuilder] showing a menu of options.
+     */
     override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
         return MaterialAlertDialogBuilder(requireContext())
             .setAdapter(
@@ -20,22 +45,56 @@ class VideoOptionsDialog : DialogFragment() {
                     R.layout.video_options_dialog_item,
                     list
                 )
-            ) { _, which ->
+            ) { dialog, which ->
                 // For now, this checks the position of the option with the position that is in the
                 // list. I don't like it, but we will do like this for now.
                 when (which) {
                     // This for example will be the "Background mode" option
-                    1 -> {
-                        TODO("Implement the background mode option")
+                    0 -> {
+                        lifecycleScope.launchWhenCreated {
+                            // FIXME: For some reason I can't get the response
+                            response = RetrofitInstance.api.getStreams(videoId)
+                            initializePlayer()
+
+                            player?.playWhenReady = playWhenReady
+                            player?.seekTo(currentItem, playbackPosition)
+                            player?.prepare()
+                        }
                     }
                     else -> {
-                        this.dismiss()
+                        dialog.dismiss()
                     }
                 }
             }
             .show()
     }
 
+    /**
+     * Initializes the [Exoplayer] player with the [MediaItem].
+     */
+    private fun initializePlayer() {
+        player = ExoPlayer.Builder(requireContext())
+            .build()
+            .also { exoPlayer ->
+                val mediaItem = MediaItem.fromUri(response.hls!!)
+                exoPlayer.setMediaItem(mediaItem)
+            }
+    }
+
+    /**
+     * Releases the [ExoPlayer].
+     */
+    private fun releasePlayer() {
+        player?.let { exoPlayer ->
+            playbackPosition = exoPlayer.currentPosition
+            currentItem = exoPlayer.currentMediaItemIndex
+            playWhenReady = exoPlayer.playWhenReady
+            exoPlayer.release()
+        }
+        player = null
+    }
+
+
     companion object {
         const val TAG = "VideoOptionsDialog"
     }

app/src/main/java/com/github/libretube/adapters/TrendingAdapter.kt

@@ -78,7 +78,8 @@ class TrendingAdapter(
                 .commitNow()
         }
         holder.v.setOnLongClickListener {
-            VideoOptionsDialog().show(childFragmentManager, VideoOptionsDialog.TAG)
+            val videoId = trending.url!!.replace("/watch?v=", "")
+            VideoOptionsDialog(videoId).show(childFragmentManager, VideoOptionsDialog.TAG)
             true
         }
     }