Unify fast-scroller

Completely unify the fast scroll indicators and the fast scroll thumb into a single view.

app/build.gradle

@@ -68,9 +68,10 @@ dependencies {
     implementation "androidx.fragment:fragment-ktx:1.3.1"
 
     // UI
+    implementation "androidx.recyclerview:recyclerview:1.1.0"
     implementation "androidx.constraintlayout:constraintlayout:2.0.4"
     implementation "androidx.dynamicanimation:dynamicanimation:1.0.0"
-    
+
     // Lifecycle
     def lifecycle_version = "2.3.0"
     implementation "androidx.lifecycle:lifecycle-common:$lifecycle_version"

app/src/main/java/org/oxycblt/auxio/music/MusicStore.kt

@@ -78,6 +78,7 @@ class MusicStore private constructor() {
      * Find a song from this instance in a safe manner.
      * Using a normal search of the songs list runs the risk of getting the *wrong* song with
      * the same name, so the album name is also used to fix the above problem.
+     * FIXME: Artist names are more unique than album names, use those
      * @param name The name of the song
      * @param albumName The name of the song's album.
      * @return The song requested, null if there isnt one.

app/src/main/java/org/oxycblt/auxio/songs/FastScrollThumb.kt

@@ -1,78 +0,0 @@
-package org.oxycblt.auxio.songs
-
-import android.content.Context
-import android.graphics.drawable.GradientDrawable
-import android.os.Build
-import android.util.AttributeSet
-import android.view.View
-import androidx.constraintlayout.widget.ConstraintLayout
-import androidx.core.view.isVisible
-import androidx.core.widget.TextViewCompat
-import androidx.dynamicanimation.animation.DynamicAnimation
-import androidx.dynamicanimation.animation.SpringAnimation
-import androidx.dynamicanimation.animation.SpringForce
-import org.oxycblt.auxio.R
-import org.oxycblt.auxio.databinding.ViewScrollThumbBinding
-import org.oxycblt.auxio.ui.Accent
-import org.oxycblt.auxio.ui.inflater
-
-/**
- * The companion thumb for [FastScrollView]. This does not need any setup, instead pass it as an
- * argument to [FastScrollView.setup].
- * This code is fundamentally an adaptation of Reddit's IndicatorFastScroll, albeit specialized
- * towards Auxio. The original library is here: https://github.com/reddit/IndicatorFastScroll/
- * @author OxygenCobalt
- */
-class FastScrollThumb @JvmOverloads constructor(
-    context: Context,
-    attrs: AttributeSet? = null,
-    defStyleAttr: Int = -1
-) : ConstraintLayout(context, attrs, defStyleAttr) {
-    private val thumbAnim: SpringAnimation
-    private val binding = ViewScrollThumbBinding.inflate(context.inflater, this, true)
-
-    init {
-        val accent = Accent.get().getStateList(context)
-
-        binding.thumbLayout.apply {
-            backgroundTintList = accent
-
-            // Workaround for API 21 tint bug
-            if (Build.VERSION.SDK_INT == Build.VERSION_CODES.LOLLIPOP) {
-                (background as GradientDrawable).apply {
-                    mutate()
-                    color = accent
-                }
-            }
-        }
-
-        binding.thumbText.apply {
-            isVisible = true
-            TextViewCompat.setTextAppearance(this, R.style.TextAppearance_ThumbIndicator)
-        }
-
-        thumbAnim = SpringAnimation(binding.thumbLayout, DynamicAnimation.TRANSLATION_Y).apply {
-            spring = SpringForce().also {
-                it.dampingRatio = SpringForce.DAMPING_RATIO_NO_BOUNCY
-            }
-        }
-
-        visibility = View.INVISIBLE
-        isActivated = false
-
-        post {
-            visibility = View.VISIBLE
-        }
-    }
-
-    /**
-     * Make the thumb jump to a new position and update its text to the given [indicator].
-     * This is not meant for use outside of the main [FastScrollView] code. Do not use it.
-     */
-    fun jumpTo(indicator: FastScrollView.Indicator, centerY: Int) {
-        binding.thumbText.text = indicator.char.toString()
-        thumbAnim.animateToFinalPosition(
-            centerY.toFloat() - (binding.thumbLayout.measuredHeight / 2)
-        )
-    }
-}

app/src/main/java/org/oxycblt/auxio/songs/FastScrollView.kt

@@ -4,22 +4,26 @@ import android.content.Context
 import android.os.Build
 import android.util.AttributeSet
 import android.util.TypedValue
-import android.view.Gravity
 import android.view.HapticFeedbackConstants
 import android.view.MotionEvent
-import android.widget.LinearLayout
-import android.widget.TextView
-import androidx.appcompat.widget.AppCompatTextView
-import androidx.core.widget.TextViewCompat
+import androidx.constraintlayout.widget.ConstraintLayout
+import androidx.core.view.isVisible
+import androidx.dynamicanimation.animation.DynamicAnimation
+import androidx.dynamicanimation.animation.SpringAnimation
+import androidx.dynamicanimation.animation.SpringForce
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
 import org.oxycblt.auxio.R
+import org.oxycblt.auxio.databinding.ViewFastScrollBinding
 import org.oxycblt.auxio.logD
 import org.oxycblt.auxio.ui.Accent
+import org.oxycblt.auxio.ui.canScroll
+import org.oxycblt.auxio.ui.inflater
 import org.oxycblt.auxio.ui.resolveAttr
 import org.oxycblt.auxio.ui.toColor
 import kotlin.math.ceil
 import kotlin.math.min
+import kotlin.math.roundToInt
 
 /**
  * A view that allows for quick scrolling through a [RecyclerView] with many items. Unlike other
@@ -32,22 +36,23 @@ class FastScrollView @JvmOverloads constructor(
     context: Context,
     attrs: AttributeSet? = null,
     defStyleAttr: Int = -1
-) : LinearLayout(context, attrs, defStyleAttr) {
+) : ConstraintLayout(context, attrs, defStyleAttr) {
 
-    // --- BASIC SETUP ---
+    // --- UI ---
+
+    private val binding = ViewFastScrollBinding.inflate(context.inflater, this, true)
+    private val thumbAnim: SpringAnimation
+
+    // --- RECYCLER ---
 
     private var mRecycler: RecyclerView? = null
-    private var mThumb: FastScrollThumb? = null
     private var mGetItem: ((Int) -> Char)? = null
 
     // --- INDICATORS ---
 
-    /** Representation of a single Indicator character in the view */
-    data class Indicator(val char: Char, val pos: Int)
+    private data class Indicator(val char: Char, val pos: Int)
 
     private var indicators = listOf<Indicator>()
-
-    private val indicatorText: TextView
     private val activeColor = Accent.get().color.toColor(context)
     private val inactiveColor = android.R.attr.textColorSecondary.resolveAttr(context)
 
@@ -59,34 +64,21 @@ class FastScrollView @JvmOverloads constructor(
     init {
         isFocusableInTouchMode = true
         isClickable = true
-        gravity = Gravity.CENTER
 
-        val textPadding = TypedValue.applyDimension(
-            TypedValue.COMPLEX_UNIT_DIP, 4F, resources.displayMetrics
-        )
-
-        // Making this entire view a TextView will cause distortions due to the touch calculations
-        // using a height that is not wrapped to the text.
-        indicatorText = AppCompatTextView(context).apply {
-            gravity = Gravity.CENTER
-            includeFontPadding = false
-
-            TextViewCompat.setTextAppearance(this, R.style.TextAppearance_FastScroll)
-            setLineSpacing(textPadding, lineSpacingMultiplier)
-            setTextColor(inactiveColor)
+        thumbAnim = SpringAnimation(binding.scrollThumb, DynamicAnimation.TRANSLATION_Y).apply {
+            spring = SpringForce().also {
+                it.dampingRatio = SpringForce.DAMPING_RATIO_NO_BOUNCY
+            }
         }
-
-        addView(indicatorText)
     }
 
     /**
      * Set up this view with a [RecyclerView] and a corresponding [FastScrollThumb].
      */
-    fun setup(recycler: RecyclerView, thumb: FastScrollThumb, getItem: (Int) -> Char) {
+    fun setup(recycler: RecyclerView, getItem: (Int) -> Char) {
         check(mRecycler == null) { "Only set up this view once." }
 
         mRecycler = recycler
-        mThumb = thumb
         mGetItem = getItem
 
         postIndicatorUpdate()
@@ -105,6 +97,9 @@ class FastScrollView @JvmOverloads constructor(
                     updateIndicators()
                 }
 
+                // Hide this view if there is nothing to scroll
+                isVisible = recycler.canScroll()
+
                 hasPostedItemUpdate = false
             }
         }
@@ -140,9 +135,9 @@ class FastScrollView @JvmOverloads constructor(
             }
         }
 
-        indicatorText.apply {
-            tag = indicators
-            text = indicators.joinToString("\n") { it.char.toString() }
+        // Then set it as the unified TextView text, for efficiency purposes.
+        binding.scrollIndicatorText.text = indicators.joinToString("\n") { indicator ->
+            indicator.char.toString()
         }
     }
 
@@ -152,37 +147,38 @@ class FastScrollView @JvmOverloads constructor(
     override fun onTouchEvent(event: MotionEvent): Boolean {
         performClick()
 
-        val success = handleTouch(event.action, event.y.toInt())
+        val success = handleTouch(event.action, event.y.roundToInt())
 
         // Depending on the results, update the visibility of the thumb and the pressed state of
         // this view.
         isPressed = success
-        mThumb?.isActivated = success
+        binding.scrollThumb.isActivated = success
 
         return success
     }
 
-    @Suppress("UNCHECKED_CAST")
     private fun handleTouch(action: Int, touchY: Int): Boolean {
         if (action == MotionEvent.ACTION_UP || action == MotionEvent.ACTION_CANCEL) {
-            indicatorText.setTextColor(inactiveColor)
+            binding.scrollIndicatorText.setTextColor(inactiveColor)
             lastPos = -1
 
             return false
         }
 
-        if (touchY in (indicatorText.top until indicatorText.bottom)) {
-            // Try to roughly caculate which indicator the user is currently touching [Since the
-            val textHeight = indicatorText.height / indicators.size
-            val indicatorIndex = min(
-                (touchY - indicatorText.top) / textHeight, indicators.lastIndex
-            )
+        // Try to figure out which indicator the pointer has landed on
+        if (touchY in (binding.scrollIndicatorText.top until binding.scrollIndicatorText.bottom)) {
+            // Get the touch position in regards to the TextView and the rough text height
+            val indicatorTouchY = touchY - binding.scrollIndicatorText.top
+            val textHeight = binding.scrollIndicatorText.height / indicators.size
 
-            val centerY = y.toInt() + (textHeight / 2) + (indicatorIndex * textHeight)
+            // Use that to calculate the indicator index, if the calculation is
+            // invalid just ignore it.
+            val index = min(indicatorTouchY / textHeight, indicators.lastIndex)
 
-            val touchedIndicator = indicators[indicatorIndex]
+            // Also calculate the rough center position of the indicator for the scroll thumb
+            val centerY = binding.scrollIndicatorText.y + (textHeight / 2) + (index * textHeight)
 
-            selectIndicator(touchedIndicator, centerY)
+            selectIndicator(indicators[index], centerY)
 
             return true
         }
@@ -190,20 +186,20 @@ class FastScrollView @JvmOverloads constructor(
         return false
     }
 
-    private fun selectIndicator(indicator: Indicator, indicatorCenterY: Int) {
+    private fun selectIndicator(indicator: Indicator, centerY: Float) {
         if (indicator.pos != lastPos) {
             lastPos = indicator.pos
-            indicatorText.setTextColor(activeColor)
+            binding.scrollIndicatorText.setTextColor(activeColor)
 
             // Stop any scroll momentum and snap-scroll to the position
             mRecycler?.apply {
                 stopScroll()
-                (layoutManager as LinearLayoutManager).scrollToPositionWithOffset(
-                    indicator.pos, 0
-                )
+                (layoutManager as LinearLayoutManager).scrollToPositionWithOffset(indicator.pos, 0)
             }
 
-            mThumb?.jumpTo(indicator, indicatorCenterY)
+            // Update the thumb position/text
+            binding.scrollThumbText.text = indicator.char.toString()
+            thumbAnim.animateToFinalPosition(centerY - (binding.scrollThumb.measuredHeight / 2))
 
             performHapticFeedback(
                 if (Build.VERSION.SDK_INT >= 27) {

app/src/main/java/org/oxycblt/auxio/songs/SongsFragment.kt

@@ -12,7 +12,6 @@ import org.oxycblt.auxio.databinding.FragmentSongsBinding
 import org.oxycblt.auxio.logD
 import org.oxycblt.auxio.music.MusicStore
 import org.oxycblt.auxio.playback.PlaybackViewModel
-import org.oxycblt.auxio.ui.canScroll
 import org.oxycblt.auxio.ui.fixAnimInfoLeak
 import org.oxycblt.auxio.ui.getSpans
 import org.oxycblt.auxio.ui.newMenu
@@ -55,17 +54,9 @@ class SongsFragment : Fragment() {
             if (spans != 1) {
                 layoutManager = GridLayoutManager(requireContext(), spans)
             }
-
-            post {
-                if (!canScroll()) {
-                    // Disable fast scrolling if there is nothing to scroll
-                    binding.songFastScroll.visibility = View.GONE
-                    binding.songFastScrollThumb.visibility = View.GONE
-                }
-            }
         }
 
-        binding.songFastScroll.setup(binding.songRecycler, binding.songFastScrollThumb) { pos ->
+        binding.songFastScroll.setup(binding.songRecycler) { pos ->
             val char = musicStore.songs[pos].name.first
 
             if (char.isDigit()) '#' else char

app/src/main/java/org/oxycblt/auxio/ui/InterfaceUtils.kt

@@ -84,7 +84,7 @@ fun Context.getPlural(@PluralsRes pluralsRes: Int, value: Int): String {
  * @param T The system service in question.
  * @param serviceClass The service's kotlin class [Java class will be used in function call]
  * @return The system service
- * @throws IllegalStateException If the system service cannot be retrieved.
+ * @throws IllegalArgumentException If the system service cannot be retrieved.
  */
 fun <T : Any> Context.getSystemServiceSafe(serviceClass: KClass<T>): T {
     return requireNotNull(ContextCompat.getSystemService(this, serviceClass.java)) {
@@ -218,7 +218,6 @@ fun Activity.isIrregularLandscape(): Boolean {
  * Check if the system bars are on the bottom.
  * @return If the system bars are on the bottom, false if no.
  */
-@Suppress("DEPRECATION")
 private fun isSystemBarOnBottom(activity: Activity): Boolean {
     val realPoint = Point()
     val metrics = DisplayMetrics()
@@ -236,6 +235,7 @@ private fun isSystemBarOnBottom(activity: Activity): Boolean {
             }
         }
     } else {
+        @Suppress("DEPRECATION")
         (activity.getSystemServiceSafe(WindowManager::class)).apply {
             defaultDisplay.getRealSize(realPoint)
             defaultDisplay.getMetrics(metrics)

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

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="oval">
+    <solid android:color="@android:color/white" />
+</shape>

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

@@ -39,13 +39,5 @@
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintTop_toBottomOf="@+id/song_toolbar" />
 
-        <org.oxycblt.auxio.songs.FastScrollThumb
-            android:id="@+id/song_fast_scroll_thumb"
-            android:layout_width="@dimen/width_thumb_view"
-            android:layout_height="0dp"
-            app:layout_constraintBottom_toBottomOf="parent"
-            app:layout_constraintEnd_toStartOf="@+id/song_fast_scroll"
-            app:layout_constraintTop_toBottomOf="@+id/song_toolbar" />
-
     </androidx.constraintlayout.widget.ConstraintLayout>
 </layout>

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

@@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout 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">
+
+    <merge
+        tools:layout_height="match_parent"
+        tools:layout_width="match_parent"
+        tools:parentTag="androidx.constraintlayout.widget.ConstraintLayout">
+
+        <FrameLayout
+            android:id="@+id/scroll_thumb"
+            android:layout_width="@dimen/size_scroll_thumb"
+            android:layout_height="@dimen/size_scroll_thumb"
+            android:background="@drawable/ui_circle"
+            android:elevation="@dimen/elevation_small"
+            android:backgroundTint="?attr/colorPrimary"
+            android:stateListAnimator="@animator/animator_thumb"
+            app:layout_constraintEnd_toStartOf="@+id/scroll_indicator_text">
+
+            <TextView
+                android:id="@+id/scroll_thumb_text"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                android:gravity="center"
+                android:textSize="@dimen/text_size_thumb"
+                android:textColor="?android:attr/windowBackground"
+                android:fontFamily="@font/inter_semibold"
+                tools:text="A" />
+
+        </FrameLayout>
+
+        <TextView
+            android:id="@+id/scroll_indicator_text"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:fontFamily="@font/inter_semibold"
+            android:gravity="center"
+            android:includeFontPadding="false"
+            android:lineSpacingExtra="@dimen/padding_tiny"
+            android:paddingTop="@dimen/padding_tiny"
+            android:paddingBottom="@dimen/padding_tiny"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintTop_toTopOf="parent"
+            tools:text="A\nB\n\C\nD\nE" />
+
+    </merge>
+</layout>

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

@@ -1,31 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- Animator from IndicatorFastScroll (https://github.com/reddit/IndicatorFastScroll) -->
-<layout>
-    <merge 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"
-        tools:layout_height="match_parent"
-        tools:layout_width="@dimen/size_scroll_thumb"
-        tools:parentTag="androidx.constraintlayout.widget.ConstraintLayout">
-
-        <FrameLayout
-            android:id="@+id/thumb_layout"
-            android:layout_width="0dp"
-            android:layout_height="0dp"
-            android:background="@drawable/ui_circular_button"
-            android:elevation="@dimen/elevation_small"
-            android:stateListAnimator="@animator/animator_thumb"
-            app:layout_constraintDimensionRatio="W,1:1"
-            app:layout_constraintEnd_toEndOf="parent"
-            app:layout_constraintStart_toStartOf="parent">
-
-            <TextView
-                android:id="@+id/thumb_text"
-                android:layout_width="match_parent"
-                android:layout_height="match_parent"
-                android:gravity="center"
-                tools:text="A" />
-
-        </FrameLayout>
-    </merge>
-</layout>

app/src/main/res/navigation/nav_main.xml

@@ -24,11 +24,6 @@
         android:name="org.oxycblt.auxio.MainFragment"
         android:label="MainFragment"
         tools:layout="@layout/fragment_main">
-        <action
-            android:id="@+id/action_return_to_loading"
-            app:destination="@id/loading_fragment"
-            app:popUpTo="@id/main_fragment"
-            app:popUpToInclusive="true" />
         <action
             android:id="@+id/action_go_to_playback"
             app:destination="@id/playback_fragment"

app/src/main/res/values/dimens.xml

@@ -40,7 +40,7 @@
 
     <dimen name="size_play_pause">70dp</dimen>
     <dimen name="size_play_pause_compact">36dp</dimen>
-    <dimen name="size_scroll_thumb">32dp</dimen>
+    <dimen name="size_scroll_thumb">48dp</dimen>
     <dimen name="size_clear">32dp</dimen>
 
     <dimen name="size_app_icon">60dp</dimen>

app/src/main/res/values/styles.xml

@@ -98,18 +98,6 @@
         <item name="android:fontFamily">@font/inter_exbold</item>
     </style>
 
-    <!-- Fast scroll text appearance -->
-    <style name="TextAppearance.FastScroll" parent="TextAppearance.AppCompat.Body2">
-        <item name="android:fontFamily">@font/inter_semibold</item>
-        <item name="android:lineSpacingExtra">@dimen/padding_tiny</item>
-    </style>
-
-    <!-- Fast scroll thumb appearance -->
-    <style name="TextAppearance.ThumbIndicator" parent="TextAppearance.FastScroll">
-        <item name="android:textSize">@dimen/text_size_thumb</item>
-        <item name="android:textColor">?android:attr/windowBackground</item>
-    </style>
-
     <!-- Style for the general item background -->
     <style name="ItemSurroundings">
         <item name="android:layout_width">match_parent</item>

build.gradle

@@ -1,23 +1,21 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 buildscript {
-    ext.kotlin_version = '1.4.31'
+    ext.kotlin_version = "1.4.31"
     ext.navigation_version = "2.3.4"
 
     repositories {
         google()
         mavenCentral()
 
-        // TODO: Eliminate Exoplayer when it migrates to GMaven
         jcenter {
             content {
                 includeGroup("org.jetbrains.trove4j")
-                includeGroup("com.google.android.exoplayer")
             }
         }
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:4.1.3'
+        classpath "com.android.tools.build:gradle:4.1.3"
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath "androidx.navigation:navigation-safe-args-gradle-plugin:$navigation_version"
 
@@ -31,9 +29,9 @@ allprojects {
         google()
         mavenCentral()
 
+        // TODO: Eliminate Exoplayer when it migrates to GMaven
         jcenter {
             content {
-                includeGroup("org.jetbrains.trove4j")
                 includeGroup("com.google.android.exoplayer")
             }
         }