Update fast scroll behavior

Update the behavior of the fast scroller so that the scroll only begins when the pointer is in the indicator box itself, instead of the general view.

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

@@ -59,6 +59,7 @@ class FastScrollView @JvmOverloads constructor(
     // --- STATE ---
 
     private var hasPostedItemUpdate = false
+    private var wasValidTouch = false
     private var lastPos = -1
 
     init {
@@ -147,6 +148,7 @@ class FastScrollView @JvmOverloads constructor(
 
     @Suppress("ClickableViewAccessibility")
     override fun onTouchEvent(event: MotionEvent): Boolean {
+        super.onTouchEvent(event)
         performClick()
 
         val success = handleTouch(event.action, event.x.roundToInt(), event.y.roundToInt())
@@ -160,15 +162,25 @@ class FastScrollView @JvmOverloads constructor(
     }
 
     private fun handleTouch(action: Int, touchX: Int, touchY: Int): Boolean {
-        if (action == MotionEvent.ACTION_UP || action == MotionEvent.ACTION_CANCEL) {
-            binding.scrollIndicatorText.setTextColor(inactiveColor)
-            lastPos = -1
+        when (action) {
+            MotionEvent.ACTION_UP, MotionEvent.ACTION_CANCEL -> {
+                binding.scrollIndicatorText.setTextColor(inactiveColor)
+                wasValidTouch = false
+                lastPos = -1
 
-            return false
+                return false
+            }
+
+            // Since this view is unified between the thumb and the indicators, we have
+            // to check if the initial pointer position was in the indicators to prevent the
+            // scroll from being triggered outside its bounds.
+            MotionEvent.ACTION_DOWN -> {
+                wasValidTouch = binding.scrollIndicatorText.contains(touchX, touchY)
+            }
         }
 
         // Try to figure out which indicator the pointer has landed on
-        if (binding.scrollIndicatorText.isBeingPressed(touchX, touchY)) {
+        if (binding.scrollIndicatorText.containsY(touchY) && wasValidTouch) {
             // 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
@@ -214,10 +226,11 @@ class FastScrollView @JvmOverloads constructor(
         }
     }
 
-    /**
-     * Returns if the pointer is currently in the view
-     */
-    private fun View.isBeingPressed(x: Int, y: Int): Boolean {
+    private fun View.contains(x: Int, y: Int): Boolean {
+        return x in (left until right) && containsY(y)
+    }
+
+    private fun View.containsY(y: Int): Boolean {
         return y in (top until bottom)
     }
 }

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/item_accent.xml

@@ -12,7 +12,7 @@
             android:id="@+id/accent"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
-            android:background="@drawable/ui_circular_button"
+            android:background="@drawable/ui_circle_ripple"
             android:padding="@dimen/margin_medium"
             android:scaleType="fitCenter"
             android:src="@drawable/ic_check"

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

@@ -12,7 +12,7 @@
             android:id="@+id/scroll_thumb"
             android:layout_width="@dimen/size_scroll_thumb"
             android:layout_height="@dimen/size_scroll_thumb"
-            android:background="@drawable/ui_circular_button"
+            android:background="@drawable/ui_circle"
             android:elevation="@dimen/elevation_small"
             android:backgroundTint="?attr/colorPrimary"
             android:stateListAnimator="@animator/animator_thumb"

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

@@ -213,7 +213,7 @@
     <style name="PlayPause">
         <item name="android:layout_height">@dimen/size_play_pause</item>
         <item name="android:layout_width">@dimen/size_play_pause</item>
-        <item name="android:background">@drawable/ui_circular_button</item>
+        <item name="android:background">@drawable/ui_circle_ripple</item>
         <item name="android:backgroundTint">?attr/colorPrimary</item>
         <item name="android:tint">?android:attr/windowBackground</item>
         <item name="android:layout_marginStart">@dimen/margin_large</item>