Improves rendering performance of the ExoPlayer

app/src/main/java/com/vitorpamplona/amethyst/ui/components/RichTextViewer.kt

@@ -43,6 +43,15 @@ import com.vitorpamplona.amethyst.service.nip19.Nip19
 import com.vitorpamplona.amethyst.ui.note.NoteCompose
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.AccountViewModel
 import com.vitorpamplona.amethyst.ui.uriToRoute
+import kotlinx.collections.immutable.ImmutableList
+import kotlinx.collections.immutable.ImmutableMap
+import kotlinx.collections.immutable.ImmutableSet
+import kotlinx.collections.immutable.persistentListOf
+import kotlinx.collections.immutable.persistentMapOf
+import kotlinx.collections.immutable.persistentSetOf
+import kotlinx.collections.immutable.toImmutableList
+import kotlinx.collections.immutable.toImmutableMap
+import kotlinx.collections.immutable.toImmutableSet
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 import java.net.MalformedURLException
@@ -108,10 +117,10 @@ fun RichTextViewer(
 @Stable
 class RichTextViewerState(
     val content: String,
-    val urlSet: Set<String>,
-    val imagesForPager: Map<String, ZoomableUrlContent>,
-    val imageList: List<ZoomableUrlContent>,
-    val customEmoji: Map<String, String>
+    val urlSet: ImmutableSet<String>,
+    val imagesForPager: ImmutableMap<String, ZoomableUrlContent>,
+    val imageList: ImmutableList<ZoomableUrlContent>,
+    val customEmoji: ImmutableMap<String, String>
 )
 
 @Composable
@@ -124,7 +133,15 @@ private fun RenderRegular(
     nav: (String) -> Unit
 ) {
     var state by remember(content) {
-        mutableStateOf(RichTextViewerState(content, emptySet(), emptyMap(), emptyList(), emptyMap()))
+        mutableStateOf(
+            RichTextViewerState(
+                content,
+                persistentSetOf(),
+                persistentMapOf(),
+                persistentListOf(),
+                persistentMapOf()
+            )
+        )
     }
 
     LaunchedEffect(key1 = content) {
@@ -146,7 +163,13 @@ private fun RenderRegular(
             val emojiMap = tags?.filter { it.size > 2 && it[0] == "emoji" }?.associate { ":${it[1]}:" to it[2] } ?: emptyMap()
 
             if (urlSet.isNotEmpty() || emojiMap.isNotEmpty()) {
-                state = RichTextViewerState(content, urlSet, imagesForPager, imageList, emojiMap)
+                state = RichTextViewerState(
+                    content,
+                    urlSet.toImmutableSet(),
+                    imagesForPager.toImmutableMap(),
+                    imageList.toImmutableList(),
+                    emojiMap.toImmutableMap()
+                )
             }
         }
     }

app/src/main/java/com/vitorpamplona/amethyst/ui/components/VideoView.kt

@@ -54,7 +54,6 @@ import coil.request.ImageRequest
 import com.google.android.exoplayer2.C
 import com.google.android.exoplayer2.ExoPlayer
 import com.google.android.exoplayer2.MediaItem
-import com.google.android.exoplayer2.MediaMetadata
 import com.google.android.exoplayer2.Player
 import com.google.android.exoplayer2.source.ProgressiveMediaSource
 import com.google.android.exoplayer2.ui.AspectRatioFrameLayout
@@ -126,17 +125,17 @@ fun VideoView(videoUri: Uri, description: String? = null, thumb: Drawable? = nul
     var exoPlayer by remember { mutableStateOf<ExoPlayer?>(null) }
 
     LaunchedEffect(key1 = videoUri) {
-        val mediaBuilder = MediaItem.Builder().setUri(videoUri)
-
-        description?.let {
-            mediaBuilder.setMediaMetadata(
-                MediaMetadata.Builder().setDisplayTitle(it).build()
-            )
+        if (exoPlayer == null) {
+            launch(Dispatchers.Default) {
+                exoPlayer = ExoPlayer.Builder(context).build()
+            }
         }
+    }
 
-        val media = mediaBuilder.build()
+    exoPlayer?.let {
+        val media = remember { MediaItem.Builder().setUri(videoUri).build() }
 
-        exoPlayer = ExoPlayer.Builder(context).build().apply {
+        it.apply {
             repeatMode = Player.REPEAT_MODE_ALL
             videoScalingMode = C.VIDEO_SCALING_MODE_SCALE_TO_FIT
             volume = if (mutedInstance.value) 0f else 1f
@@ -151,9 +150,7 @@ fun VideoView(videoUri: Uri, description: String? = null, thumb: Drawable? = nul
             }
             prepare()
         }
-    }
 
-    exoPlayer?.let {
         RenderVideoPlayer(it, context, thumb, onDialog, mutedInstance)
     }
 
@@ -232,14 +229,11 @@ fun Modifier.onVisibilityChanges(onVisibilityChanges: (Boolean) -> Unit): Modifi
     val view = LocalView.current
     var isVisible: Boolean? by remember { mutableStateOf(null) }
 
-    LaunchedEffect(isVisible) {
-        onVisibilityChanges(isVisible == true)
-    }
-
     onGloballyPositioned { coordinates ->
         val newIsVisible = coordinates.isCompletelyVisible(view)
         if (isVisible != newIsVisible) {
             isVisible = newIsVisible
+            onVisibilityChanges(isVisible == true)
         }
     }
 }