Bottom nav now snaps to bottom or top after scroll

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

@@ -235,7 +235,6 @@ class LibraryController(
                     showCategoryText(currentCategory.name)
                 }
             }
-            updateFilterSheetY()
             val savedCurrentCategory = getHeader(true)?.category ?: return
             if (savedCurrentCategory.order != lastUsedCategory) {
                 lastUsedCategory = savedCurrentCategory.order
@@ -252,7 +251,6 @@ class LibraryController(
                 }
                 RecyclerView.SCROLL_STATE_IDLE -> {
                     updateHopperPosition()
-                    updateFilterSheetY()
                 }
             }
         }
@@ -262,7 +260,6 @@ class LibraryController(
         val bottomBar = activity?.bottom_nav
         filter_bottom_sheet ?: return
         if (bottomBar != null) {
-            updateHopperY()
             if (filter_bottom_sheet.sheetBehavior.isHidden()) {
                 val pad = bottomBar.translationY - bottomBar.height
                 filter_bottom_sheet.translationY = pad
@@ -283,6 +280,7 @@ class LibraryController(
                 view?.rootWindowInsets?.getBottomGestureInsets() ?: 0
             )
             filter_bottom_sheet.sheetBehavior?.peekHeight = 60.dpToPx + padding
+            updateHopperY()
             fast_scroller.updateLayoutParams<ViewGroup.MarginLayoutParams> {
                 bottomMargin = -pad.toInt()
             }
@@ -387,9 +385,6 @@ class LibraryController(
 
         adapter = LibraryCategoryAdapter(this)
         setRecyclerLayout()
-        recycler.post {
-            updateFilterSheetY()
-        }
 
         recycler.manager.spanSizeLookup = (
             object : GridLayoutManager.SpanSizeLookup() {
@@ -442,6 +437,9 @@ class LibraryController(
                 },
                 onLeavingController = {
                     header_title?.gone()
+                },
+                onBottomNavUpdate = {
+                    updateFilterSheetY()
                 }
             )
 

app/src/main/java/eu/kanade/tachiyomi/ui/recents/RecentsController.kt

@@ -134,6 +134,9 @@ class RecentsController(bundle: Bundle? = null) :
             afterInsets = {
                 headerHeight = it.systemWindowInsetTop + appBarHeight
                 recycler.updatePaddingRelative(bottom = activity!!.bottom_nav.height)
+            },
+            onBottomNavUpdate = {
+                setBottomPadding()
             }
         )
 
@@ -144,17 +147,6 @@ class RecentsController(bundle: Bundle? = null) :
                 adapter.addScrollableHeader(presenter.generalHeader)
             }
         }
-        recycler?.post {
-            setBottomPadding()
-        }
-        recycler.addOnScrollListener(
-            object : RecyclerView.OnScrollListener() {
-                override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
-                    super.onScrolled(recyclerView, dx, dy)
-                    setBottomPadding()
-                }
-            }
-        )
 
         dl_bottom_sheet.onCreate(this)
 

app/src/main/java/eu/kanade/tachiyomi/ui/source/SourceController.kt

@@ -13,7 +13,6 @@ import android.view.ViewGroup
 import androidx.appcompat.widget.SearchView
 import androidx.core.content.ContextCompat
 import androidx.core.graphics.ColorUtils
-import androidx.recyclerview.widget.RecyclerView
 import com.bluelinelabs.conductor.ControllerChangeHandler
 import com.bluelinelabs.conductor.ControllerChangeType
 import com.bluelinelabs.conductor.RouterTransaction
@@ -153,21 +152,15 @@ class SourceController :
             afterInsets = {
                 headerHeight = it.systemWindowInsetTop + appBarHeight
                 recycler.updatePaddingRelative(bottom = activity?.bottom_nav?.height ?: 0)
+            },
+            onBottomNavUpdate = {
+                setBottomPadding()
             }
         )
 
         recycler?.post {
-            setBottomPadding()
             setBottomSheetTabs(if (ext_bottom_sheet?.sheetBehavior.isCollapsed()) 0f else 1f)
         }
-        recycler.addOnScrollListener(
-            object : RecyclerView.OnScrollListener() {
-                override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
-                    super.onScrolled(recyclerView, dx, dy)
-                    setBottomPadding()
-                }
-            }
-        )
 
         requestPermissionsSafe(arrayOf(WRITE_EXTERNAL_STORAGE), 301)
         ext_bottom_sheet.onCreate(this)
@@ -230,7 +223,6 @@ class SourceController :
 
     fun setBottomSheetTabs(progress: Float) {
         val bottomSheet = ext_bottom_sheet ?: return
-        val bottomBar = activity?.bottom_nav ?: return
         ext_bottom_sheet.tabs.updateLayoutParams<ViewGroup.MarginLayoutParams> {
             topMargin = ((activity?.appbar?.height?.minus(9f.dpToPx) ?: 0f) * progress).toInt()
         }

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

@@ -104,7 +104,8 @@ fun Controller.scrollViewWith(
     swipeRefreshLayout: SwipeRefreshLayout? = null,
     afterInsets: ((WindowInsets) -> Unit)? = null,
     liftOnScroll: ((Boolean) -> Unit)? = null,
-    onLeavingController: (() -> Unit)? = null
+    onLeavingController: (() -> Unit)? = null,
+    onBottomNavUpdate: (() -> Unit)? = null
 ): ((Boolean) -> Unit) {
     var statusBarHeight = -1
     activity?.appbar?.y = 0f
@@ -120,6 +121,9 @@ fun Controller.scrollViewWith(
             recycler.requestApplyInsets()
         }
     }
+    recycler.post {
+        onBottomNavUpdate?.invoke()
+    }
     val randomTag = Random.nextLong()
     var lastY = 0f
     var fakeToolbarView: View? = null
@@ -219,10 +223,17 @@ fun Controller.scrollViewWith(
                         val shortAnimationDuration = resources?.getInteger(
                             android.R.integer.config_shortAnimTime
                         ) ?: 0
-                        activity!!.appbar.animate().y(0f).setDuration(shortAnimationDuration.toLong())
+                        activity!!.appbar.animate().y(0f)
+                            .setDuration(shortAnimationDuration.toLong())
                             .start()
-                        activity!!.bottom_nav?.animate()?.translationYBy(0f)?.setDuration(shortAnimationDuration.toLong())
-                            ?.start()
+                        activity!!.bottom_nav?.let {
+                            val animator = it.animate()?.translationY(0f)
+                                ?.setDuration(shortAnimationDuration.toLong())
+                            animator?.setUpdateListener {
+                                onBottomNavUpdate?.invoke()
+                            }
+                            animator?.start()
+                        }
                         lastY = 0f
                         if (elevate) elevateFunc(false)
                     } else {
@@ -243,6 +254,7 @@ fun Controller.scrollViewWith(
                                     tabBar.height.toFloat()
                                 )
                                 activity!!.bottom_view?.translationY = tabBar.translationY
+                                onBottomNavUpdate?.invoke()
                             } else if (tabBar.translationY != 0f) {
                                 tabBar.translationY = 0f
                                 activity!!.bottom_view?.translationY = 0f
@@ -279,6 +291,17 @@ fun Controller.scrollViewWith(
                         val atTop = !recycler.canScrollVertically(-1)
                         lastY = if (closerToTop && !atTop) (-activity!!.appbar.height.toFloat()) else 0f
                         activity!!.appbar.animate().y(lastY).setDuration(shortAnimationDuration.toLong()).start()
+                        activity!!.bottom_nav?.let {
+                            val halfWayBottom = abs((it.height.toFloat()) / 2)
+                            val closerToBottom = it.translationY > halfWayBottom
+                            val lastBottomY = if (closerToBottom && !atTop) it.height.toFloat() else 0f
+                            val animator = it.animate()?.translationY(lastBottomY)
+                                ?.setDuration(shortAnimationDuration.toLong())
+                            animator?.setUpdateListener {
+                                onBottomNavUpdate?.invoke()
+                            }
+                            animator?.start()
+                        }
                         if (recycler.canScrollVertically(-1) && !elevate) elevateFunc(true)
                         else if (!recycler.canScrollVertically(-1) && elevate) elevateFunc(false)
                     }