Improve screen transitions

app/src/main/kotlin/it/vfsfitvnm/vimusic/ui/components/themed/MediaItemMenu.kt

@@ -3,6 +3,8 @@ package it.vfsfitvnm.vimusic.ui.components.themed
 import android.content.Intent
 import android.text.format.DateUtils
 import androidx.compose.animation.AnimatedContentScope
+import androidx.compose.animation.EnterTransition
+import androidx.compose.animation.ExitTransition
 import androidx.compose.animation.ExperimentalAnimationApi
 import androidx.compose.animation.with
 import androidx.compose.foundation.background
@@ -35,7 +37,6 @@ import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.unit.dp
 import androidx.media3.common.MediaItem
 import it.vfsfitvnm.route.RouteHandler
-import it.vfsfitvnm.route.empty
 import it.vfsfitvnm.vimusic.Database
 import it.vfsfitvnm.vimusic.LocalPlayerServiceBinder
 import it.vfsfitvnm.vimusic.R
@@ -282,7 +283,7 @@ fun MediaItemMenu(
                     else -> when (initialState.route) {
                         viewPlaylistsRoute -> slideIntoContainer(AnimatedContentScope.SlideDirection.Right) with
                                 slideOutOfContainer(AnimatedContentScope.SlideDirection.Right)
-                        else -> empty
+                        else -> EnterTransition.None with ExitTransition.None
                     }
                 }
             }

app/src/main/kotlin/it/vfsfitvnm/vimusic/ui/screens/home/HomeScreen.kt

@@ -5,6 +5,12 @@ import androidx.compose.foundation.ExperimentalFoundationApi
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.saveable.rememberSaveableStateHolder
 import it.vfsfitvnm.route.RouteHandler
+import it.vfsfitvnm.route.defaultStacking
+import it.vfsfitvnm.route.defaultStill
+import it.vfsfitvnm.route.defaultUnstacking
+import it.vfsfitvnm.route.isStacking
+import it.vfsfitvnm.route.isUnknown
+import it.vfsfitvnm.route.isUnstacking
 import it.vfsfitvnm.vimusic.Database
 import it.vfsfitvnm.vimusic.R
 import it.vfsfitvnm.vimusic.models.SearchQuery
@@ -33,7 +39,21 @@ import it.vfsfitvnm.vimusic.utils.rememberPreference
 fun HomeScreen(onPlaylistUrl: (String) -> Unit) {
     val saveableStateHolder = rememberSaveableStateHolder()
 
-    RouteHandler(listenToGlobalEmitter = true) {
+    RouteHandler(
+        listenToGlobalEmitter = true,
+        transitionSpec = {
+            when {
+                isStacking -> defaultStacking
+                isUnstacking -> defaultUnstacking
+                isUnknown -> when {
+                    initialState.route == searchRoute && targetState.route == searchResultRoute -> defaultStacking
+                    initialState.route == searchResultRoute && targetState.route == searchRoute -> defaultUnstacking
+                    else -> defaultStill
+                }
+                else -> defaultStill
+            }
+        }
+    ) {
         globalRoutes()
 
         settingsRoute {
@@ -65,6 +85,7 @@ fun HomeScreen(onPlaylistUrl: (String) -> Unit) {
             SearchScreen(
                 initialTextInput = initialTextInput,
                 onSearch = { query ->
+                    pop()
                     searchResultRoute(query)
 
                     query {

compose-routing/src/main/kotlin/it/vfsfitvnm/route/RouteHandler.kt

@@ -21,7 +21,13 @@ fun RouteHandler(
     modifier: Modifier = Modifier,
     listenToGlobalEmitter: Boolean = false,
     handleBackPress: Boolean = true,
-    transitionSpec: AnimatedContentScope<RouteHandlerScope>.() -> ContentTransform = { fastFade },
+    transitionSpec: AnimatedContentScope<RouteHandlerScope>.() -> ContentTransform = {
+        when {
+            isStacking -> defaultStacking
+            isStill -> defaultStill
+            else -> defaultUnstacking
+        }
+    },
     content: @Composable RouteHandlerScope.() -> Unit
 ) {
     var route by rememberSaveable(stateSaver = Route.Saver) {
@@ -47,7 +53,13 @@ fun RouteHandler(
     modifier: Modifier = Modifier,
     listenToGlobalEmitter: Boolean = false,
     handleBackPress: Boolean = true,
-    transitionSpec: AnimatedContentScope<RouteHandlerScope>.() -> ContentTransform = { fastFade },
+    transitionSpec: AnimatedContentScope<RouteHandlerScope>.() -> ContentTransform = {
+        when {
+            isStacking -> defaultStacking
+            isStill -> defaultStill
+            else -> defaultUnstacking
+        }
+    },
     content: @Composable RouteHandlerScope.() -> Unit
 ) {
     val backDispatcher = LocalOnBackPressedDispatcherOwner.current?.onBackPressedDispatcher

compose-routing/src/main/kotlin/it/vfsfitvnm/route/Transitions.kt

@@ -3,27 +3,44 @@ package it.vfsfitvnm.route
 import androidx.compose.animation.AnimatedContentScope
 import androidx.compose.animation.ContentTransform
 import androidx.compose.animation.EnterTransition
-import androidx.compose.animation.ExitTransition
 import androidx.compose.animation.ExperimentalAnimationApi
-import androidx.compose.animation.core.tween
 import androidx.compose.animation.fadeIn
 import androidx.compose.animation.fadeOut
-import androidx.compose.animation.with
+import androidx.compose.animation.scaleOut
 
 @ExperimentalAnimationApi
-val AnimatedContentScope<RouteHandlerScope>.leftSlide: ContentTransform
-    get() = slideIntoContainer(AnimatedContentScope.SlideDirection.Left) with
-            slideOutOfContainer(AnimatedContentScope.SlideDirection.Left)
+val defaultStacking = ContentTransform(
+    initialContentExit = scaleOut(targetScale = 0.9f) + fadeOut(),
+    targetContentEnter = fadeIn(),
+    targetContentZIndex = 1f
+)
 
 @ExperimentalAnimationApi
-val AnimatedContentScope<RouteHandlerScope>.rightSlide: ContentTransform
-    get() = slideIntoContainer(AnimatedContentScope.SlideDirection.Right) with
-            slideOutOfContainer(AnimatedContentScope.SlideDirection.Right)
+val defaultUnstacking = ContentTransform(
+    initialContentExit = fadeOut(),
+    targetContentEnter = EnterTransition.None,
+    targetContentZIndex = 0f
+)
 
 @ExperimentalAnimationApi
-val AnimatedContentScope<RouteHandlerScope>.fastFade: ContentTransform
-    get() = fadeIn(tween(200)) with fadeOut(tween(200))
+val defaultStill = ContentTransform(
+    initialContentExit = scaleOut(targetScale = 0.9f) + fadeOut(),
+    targetContentEnter = fadeIn(),
+    targetContentZIndex = 1f
+)
 
 @ExperimentalAnimationApi
-val AnimatedContentScope<RouteHandlerScope>.empty: ContentTransform
-    get() = EnterTransition.None with ExitTransition.None
+inline val AnimatedContentScope<RouteHandlerScope>.isStacking: Boolean
+    get() = initialState.route == null && targetState.route != null
+
+@ExperimentalAnimationApi
+inline val AnimatedContentScope<RouteHandlerScope>.isUnstacking: Boolean
+    get() = initialState.route != null && targetState.route == null
+
+@ExperimentalAnimationApi
+inline val AnimatedContentScope<RouteHandlerScope>.isStill: Boolean
+    get() = initialState.route == null && targetState.route == null
+
+@ExperimentalAnimationApi
+inline val AnimatedContentScope<RouteHandlerScope>.isUnknown: Boolean
+    get() = initialState.route != null && targetState.route != null