From 5639fe4517ba9137ea96a32f254d586a8f899c1f Mon Sep 17 00:00:00 2001
From: Kirill Kamakin <k.kamakin@protonmail.ch>
Date: Sun, 21 Nov 2021 20:45:15 +0300
Subject: [PATCH] Implement toolbar hiding on scroll

---
 .../java/gq/kirmanak/mealient/MainActivity.kt |  1 +
 app/src/main/res/layout/main_activity.xml     | 29 ++++++++++++-------
 2 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/app/src/main/java/gq/kirmanak/mealient/MainActivity.kt b/app/src/main/java/gq/kirmanak/mealient/MainActivity.kt
index cd0da6d..c068336 100644
--- a/app/src/main/java/gq/kirmanak/mealient/MainActivity.kt
+++ b/app/src/main/java/gq/kirmanak/mealient/MainActivity.kt
@@ -31,6 +31,7 @@ class MainActivity : AppCompatActivity() {
     private fun setToolbarRoundCorner() {
         Timber.v("setToolbarRoundCorner() called")
         val drawables = listOf(
+            binding.toolbarHolder.background as? MaterialShapeDrawable,
             binding.toolbar.background as? MaterialShapeDrawable,
         )
         Timber.d("setToolbarRoundCorner: drawables = $drawables")
diff --git a/app/src/main/res/layout/main_activity.xml b/app/src/main/res/layout/main_activity.xml
index 4b4b4c9..3986213 100644
--- a/app/src/main/res/layout/main_activity.xml
+++ b/app/src/main/res/layout/main_activity.xml
@@ -1,29 +1,38 @@
 <?xml version="1.0" encoding="utf-8"?>
-<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
 	xmlns:app="http://schemas.android.com/apk/res-auto"
 	xmlns:tools="http://schemas.android.com/tools"
 	android:layout_width="match_parent"
 	android:layout_height="match_parent"
 	tools:context=".MainActivity">
 
-	<com.google.android.material.appbar.MaterialToolbar
-		android:id="@+id/toolbar"
-		style="@style/Widget.MaterialComponents.Toolbar.Primary"
+	<com.google.android.material.appbar.AppBarLayout
+		android:id="@+id/toolbar_holder"
+		android:layout_width="match_parent"
 		android:layout_height="wrap_content"
+		app:layout_constraintTop_toTopOf="parent"
 		app:layout_constraintEnd_toEndOf="parent"
 		app:layout_constraintStart_toStartOf="parent"
-		android:layout_width="match_parent"
-		app:layout_constraintTop_toTopOf="parent" />
+		app:liftOnScroll="true">
+
+		<com.google.android.material.appbar.MaterialToolbar
+			android:id="@+id/toolbar"
+			style="@style/Widget.MaterialComponents.Toolbar.Primary"
+			android:layout_width="match_parent"
+			android:layout_height="?actionBarSize"
+			app:layout_scrollFlags="scroll|snap" />
+	</com.google.android.material.appbar.AppBarLayout>
 
 	<androidx.fragment.app.FragmentContainerView
 		android:id="@+id/nav_host"
 		android:name="androidx.navigation.fragment.NavHostFragment"
-		android:layout_width="0dp"
-		android:layout_height="0dp"
+		android:layout_width="match_parent"
+		android:layout_height="match_parent"
+		app:layout_behavior="@string/appbar_scrolling_view_behavior"
 		app:defaultNavHost="true"
 		app:layout_constraintBottom_toBottomOf="parent"
 		app:layout_constraintEnd_toEndOf="parent"
 		app:layout_constraintStart_toStartOf="parent"
-		app:layout_constraintTop_toBottomOf="@+id/toolbar"
+		app:layout_constraintTop_toBottomOf="@+id/toolbar_holder"
 		app:navGraph="@navigation/nav_graph" />
-</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
+</androidx.coordinatorlayout.widget.CoordinatorLayout>
\ No newline at end of file