MD2'ified the category list hopper

Also library recycler now scrolls a bit to match the padding when exposing the list

app/src/main/java/eu/kanade/tachiyomi/ui/library/LibraryController.kt

@@ -172,7 +172,7 @@ class LibraryController(
                 preferences.lastUsedCategory().set(order)
                 activeCategory = order
                 setActiveCategory()
-                if (presenter.categories.size > 1 && dy != 0) {
+                if (presenter.categories.size > 1 && dy != 0 && recyclerView.translationY == 0f) {
                     val headerItem = getHeader() ?: return
                     val view = fast_scroller ?: return
 
@@ -334,7 +334,7 @@ class LibraryController(
         }
         category_recycler.onCategoryClicked = {
             scrollToHeader(it)
-            showCategories(false)
+            showCategories(show = false, scroll = false)
         }
         category_recycler.onShowAllClicked = { isChecked ->
             preferences.showAllCategories().set(isChecked)
@@ -601,15 +601,29 @@ class LibraryController(
         }
     }
 
-    private fun showCategories(show: Boolean) {
+    private fun showCategories(show: Boolean, scroll: Boolean = true) {
         recycler_cover.isClickable = show
         recycler_cover.isFocusable = show
-        val translateY = if (show) {
+        val full = category_layout.height.toFloat() + recycler.paddingTop
-            category_layout.height.toFloat() + recycler.paddingTop
+        val translateY = if (show) full else 0f
-        } else {
-            0f
-        }
         recycler.animate().translationY(translateY).start()
+        if (scroll) {
+            // Smooth scroll the recycler to hide the hidden content blocked by the app bar
+            ValueAnimator.ofInt(recycler.translationY.roundToInt(), translateY.roundToInt()).apply {
+                var start = 0f
+                var last = recycler.translationY.roundToInt()
+                val distance = abs(recycler.translationY.roundToInt() - translateY.roundToInt())
+                addUpdateListener {
+                    val diff = abs(it.animatedValue as Int - last)
+                    last = it.animatedValue as Int
+                    start += diff.toFloat() / distance * recycler.paddingTop.toFloat()
+                    if (start > 1) {
+                        recycler.scrollBy(0, start.toInt() * if (show) 1 else -1)
+                        start %= 1
+                    }
+                }
+            }.start()
+        }
         recycler_cover.animate().translationY(translateY).start()
         recycler_cover.animate().alpha(if (show) 0.75f else 0f).start()
         if (show) {

app/src/main/res/drawable/material_list_item_selector.xml

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="utf-8"?>
+<ripple xmlns:android="http://schemas.android.com/apk/res/android"
+    android:color="@color/fullRippleColor">
+    <item android:id="@android:id/mask"
+        android:left="12dp"
+        android:right="12dp">
+        <shape android:shape="rectangle">
+            <corners android:radius="4dp" />
+            <solid android:color="@color/fullRippleColor" />
+        </shape>
+    </item>
+    <item
+        android:left="12dp"
+        android:right="12dp">
+        <selector>
+            <item android:state_selected="true">
+                <shape android:shape="rectangle">
+                    <corners android:radius="4dp" />
+                    <solid android:color="@color/rippleColor" />
+                </shape>
+            </item>
+
+            <item android:state_activated="true">
+                <shape android:shape="rectangle">
+                    <corners android:radius="4dp" />
+                    <solid android:color="@color/fullRippleColor" />
+                </shape>
+            </item>
+
+            <item android:id="@android:id/mask">
+                <shape android:shape="rectangle">
+                    <corners android:radius="4dp" />
+                    <solid android:color="?android:colorBackground" />
+                </shape>
+            </item>
+        </selector>
+    </item>
+</ripple>

app/src/main/res/drawable/square_ripple.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <ripple xmlns:android="http://schemas.android.com/apk/res/android"
-    android:color="@color/gray_button">
+    android:color="@color/fullRippleColor">
     <item android:id="@android:id/mask">
         <shape android:shape="rectangle">
             <corners android:radius="4dp" />

app/src/main/res/layout/catergory_text_view.xml

@@ -1,20 +1,16 @@
 <?xml version="1.0" encoding="utf-8"?>
-<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<com.google.android.material.textview.MaterialTextView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/category_text"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
-    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_marginTop="2dp"
-    android:background="@drawable/list_item_selector">
+    android:layout_marginBottom="2dp"
-
+    android:background="@drawable/material_list_item_selector"
-    <com.google.android.material.textview.MaterialTextView
+    android:paddingStart="24dp"
-        android:id="@+id/category_text"
+    android:paddingTop="8dp"
-        android:layout_width="match_parent"
+    android:paddingEnd="0dp"
-        android:layout_height="wrap_content"
+    android:paddingBottom="8dp"
-        android:background="@drawable/list_item_selector"
+    android:textAppearance="@style/TextAppearance.MaterialComponents.Headline6"
-        android:paddingStart="12dp"
+    android:textSize="16sp"
-        android:paddingTop="8dp"
+    tools:text="@string/categories" />
-        android:paddingEnd="0dp"
-        android:paddingBottom="8dp"
-        tools:text="@string/categories"
-        android:textAppearance="@style/TextAppearance.MaterialComponents.Headline6"
-        android:textSize="16sp" />
-</FrameLayout>

app/src/main/res/layout/library_list_controller.xml

@@ -33,6 +33,7 @@
                     android:id="@+id/category_recycler"
                     android:layout_width="0dp"
                     android:layout_height="wrap_content"
+                    android:paddingBottom="4dp"
                     app:layout_constraintBottom_toBottomOf="parent"
                     app:layout_constraintEnd_toEndOf="parent"
                     app:layout_constraintStart_toStartOf="parent"