Add text to chapter FAB, shrink extended FABs on scroll

app/src/main/java/eu/kanade/tachiyomi/ui/catalogue/browse/BrowseCatalogueController.kt

@@ -36,6 +36,7 @@ import eu.kanade.tachiyomi.util.system.connectivityManager
 import eu.kanade.tachiyomi.util.system.toast
 import eu.kanade.tachiyomi.util.view.gone
 import eu.kanade.tachiyomi.util.view.inflate
+import eu.kanade.tachiyomi.util.view.shrinkOnScroll
 import eu.kanade.tachiyomi.util.view.snack
 import eu.kanade.tachiyomi.util.view.visible
 import eu.kanade.tachiyomi.widget.AutofitRecyclerView
@@ -203,8 +204,8 @@ open class BrowseCatalogueController(bundle: Bundle) :
             }
         }
 
-        // Add bottom padding if filter FAB is visible
         if (presenter.sourceFilters.isNotEmpty()) {
+            // Add bottom padding if filter FAB is visible
             recycler.setPadding(
                 0,
                 0,
@@ -212,6 +213,8 @@ open class BrowseCatalogueController(bundle: Bundle) :
                 view.resources.getDimensionPixelOffset(R.dimen.fab_list_padding)
             )
             recycler.clipToPadding = false
+
+            binding.fabFilter.shrinkOnScroll(recycler)
         }
 
         recycler.setHasFixedSize(true)

app/src/main/java/eu/kanade/tachiyomi/ui/manga/chapter/ChaptersController.kt

@@ -32,6 +32,7 @@ import eu.kanade.tachiyomi.ui.reader.ReaderActivity
 import eu.kanade.tachiyomi.util.system.getResourceColor
 import eu.kanade.tachiyomi.util.system.toast
 import eu.kanade.tachiyomi.util.view.getCoordinates
+import eu.kanade.tachiyomi.util.view.shrinkOnScroll
 import eu.kanade.tachiyomi.util.view.snack
 import timber.log.Timber
 
@@ -110,6 +111,7 @@ class ChaptersController : NucleusController<ChaptersPresenter>(),
                 view.context.toast(R.string.no_next_chapter)
             }
         }
+        binding.fab.shrinkOnScroll(binding.recycler)
     }
 
     override fun onDestroyView(view: View) {

app/src/main/java/eu/kanade/tachiyomi/util/view/ViewExtensions.kt

@@ -13,8 +13,10 @@ import android.widget.ImageView
 import android.widget.TextView
 import androidx.annotation.MenuRes
 import androidx.appcompat.widget.PopupMenu
+import androidx.recyclerview.widget.RecyclerView
 import com.amulyakhare.textdrawable.TextDrawable
 import com.amulyakhare.textdrawable.util.ColorGenerator
+import com.google.android.material.floatingactionbutton.ExtendedFloatingActionButton
 import com.google.android.material.snackbar.Snackbar
 import eu.kanade.tachiyomi.R
 import kotlin.math.min
@@ -94,3 +96,19 @@ fun ImageView.roundTextIcon(text: String) {
             )
     )
 }
+
+/**
+ * Shrink an ExtendedFloatingActionButton when the associated RecyclerView is scrolled down.
+ *
+ * @param recycler [RecyclerView] that the FAB should shrink/extend in response to.
+ */
+fun ExtendedFloatingActionButton.shrinkOnScroll(recycler: RecyclerView) {
+    recycler.addOnScrollListener(object : RecyclerView.OnScrollListener() {
+        override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
+            if (dy <= 0)
+                extend()
+            else
+                shrink()
+        }
+    })
+}

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

@@ -50,10 +50,11 @@
         android:layout_height="wrap_content"
         android:layout_gravity="bottom" />
 
-    <com.google.android.material.floatingactionbutton.FloatingActionButton
+    <com.google.android.material.floatingactionbutton.ExtendedFloatingActionButton
         android:id="@+id/fab"
         style="@style/Theme.Widget.FAB"
+        android:text="@string/action_resume"
         app:layout_anchor="@id/recycler"
-        app:srcCompat="@drawable/ic_play_arrow_24dp" />
+        app:icon="@drawable/ic_play_arrow_24dp" />
 
 </androidx.coordinatorlayout.widget.CoordinatorLayout>