[Slider] Add mouse support for slider control.

This change makes it so that mouse input does not behave exactly like touch when using a slider. Previously, any time a touch event was detected on a slider bar, we would postpone updating the slider position because there was potential for a pan drag if the container was a scrollable view. See cl/286431744. However for mouse input this should never apply because a mouse down event should not be able to scroll the container.

This change also fixes the halo not updating when clicking or touching down on the slider (without dragging). This isn't very noticeable when only using touch input but when hovering over the control with a mouse, you can see the halo was in the last position of the slider instead of the current position.

PiperOrigin-RevId: 495905645

Author: Material Design Team

lib/java/com/google/android/material/slider/BaseSlider.java

@@ -1943,7 +1943,7 @@ public boolean onTouchEvent(@NonNull MotionEvent event) {
 
         // If we're inside a vertical scrolling container,
         // we should start dragging in ACTION_MOVE
-        if (isInVerticalScrollingContainer()) {
+        if (isPotentialVerticalScroll(event)) {
           break;
         }
 
@@ -1964,7 +1964,7 @@ public boolean onTouchEvent(@NonNull MotionEvent event) {
       case MotionEvent.ACTION_MOVE:
         if (!thumbIsPressed) {
           // Check if we're trying to scroll vertically instead of dragging this Slider
-          if (isInVerticalScrollingContainer() && abs(x - touchDownX) < scaledTouchSlop) {
+          if (isPotentialVerticalScroll(event) && abs(x - touchDownX) < scaledTouchSlop) {
             return false;
           }
           getParent().requestDisallowInterceptTouchEvent(true);
@@ -1996,6 +1996,7 @@ && abs(lastEvent.getY() - event.getY()) <= scaledTouchSlop) {
 
         if (activeThumbIdx != -1) {
           snapTouchPosition();
+          updateHaloHotspot();
           activeThumbIdx = -1;
           onStopTrackingTouch();
         }
@@ -2347,6 +2348,14 @@ private boolean isInVerticalScrollingContainer() {
     return false;
   }
 
+  private static boolean isMouseEvent(MotionEvent event) {
+    return event.getToolType(0) == MotionEvent.TOOL_TYPE_MOUSE;
+  }
+
+  private boolean isPotentialVerticalScroll(MotionEvent event) {
+    return !isMouseEvent(event) && isInVerticalScrollingContainer();
+  }
+
   @SuppressWarnings("unchecked")
   private void dispatchOnChangedProgrammatically() {
     for (L listener : changeListeners) {