Disables StateListAnimator for React Slider Android 6 and 7

Summary:
This diff disables the StateListAnimator for the ReactSlider component in Android 6 and 7
This is this is a hack to prevent T37452851 and https://github.com/facebook/react-native/issues/9979

Reviewed By: yungsters

Differential Revision: D13404685

fbshipit-source-id: d4c4f8796664c890f6a6b3502d3493370e17c300

ReactAndroid/src/main/java/com/facebook/react/views/slider/ReactSlider.java

@@ -1,57 +1,64 @@
 /**
  * Copyright (c) Facebook, Inc. and its affiliates.
  *
- * This source code is licensed under the MIT license found in the
+ * <p>This source code is licensed under the MIT license found in the LICENSE file in the root
- * LICENSE file in the root directory of this source tree.
+ * directory of this source tree.
  */
-
 package com.facebook.react.views.slider;
 
 import android.content.Context;
+import android.os.Build;
 import android.util.AttributeSet;
 import android.widget.SeekBar;
-
 import javax.annotation.Nullable;
 
 /**
  * Slider that behaves more like the iOS one, for consistency.
  *
- * On iOS, the value is 0..1. Android SeekBar only supports integer values.
+ * <p>On iOS, the value is 0..1. Android SeekBar only supports integer values. For consistency, we
- * For consistency, we pretend in JS that the value is 0..1 but set the
+ * pretend in JS that the value is 0..1 but set the SeekBar value to 0..100.
- * SeekBar value to 0..100.
  *
- * Note that the slider is _not_ a controlled component (setValue isn't called
+ * <p>Note that the slider is _not_ a controlled component (setValue isn't called during dragging).
- * during dragging).
  */
 public class ReactSlider extends SeekBar {
 
   /**
-   * If step is 0 (unset) we default to this total number of steps.
+   * If step is 0 (unset) we default to this total number of steps. Don't use 100 which leads to
-   * Don't use 100 which leads to rounding errors (0.200000000001).
+   * rounding errors (0.200000000001).
    */
   private static int DEFAULT_TOTAL_STEPS = 128;
 
   /**
-   * We want custom min..max range.
+   * We want custom min..max range. Android only supports 0..max range so we implement this
-   * Android only supports 0..max range so we implement this ourselves.
+   * ourselves.
    */
   private double mMinValue = 0;
+
   private double mMaxValue = 0;
 
   /**
-   * Value sent from JS (setState).
+   * Value sent from JS (setState). Doesn't get updated during drag (slider is not a controlled
-   * Doesn't get updated during drag (slider is not a controlled component).
+   * component).
    */
   private double mValue = 0;
 
-  /**
+  /** If zero it's determined automatically. */
-   * If zero it's determined automatically.
-   */
   private double mStep = 0;
+
   private double mStepCalculated = 0;
 
   public ReactSlider(Context context, @Nullable AttributeSet attrs, int style) {
     super(context, attrs, style);
+    disableStateListAnimatorIfNeeded();
+  }
+
+  private void disableStateListAnimatorIfNeeded() {
+    // We disable the state list animator for Android 6 and 7; this is a hack to prevent T37452851
+    // and https://github.com/facebook/react-native/issues/9979
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M
+        && Build.VERSION.SDK_INT < Build.VERSION_CODES.O) {
+      super.setStateListAnimator(null);
+    }
   }
 
   /* package */ void setMaxValue(double max) {
@@ -75,8 +82,7 @@ public class ReactSlider extends SeekBar {
   }
 
   /**
-   * Convert SeekBar's native progress value (e.g. 0..100) to a value
+   * Convert SeekBar's native progress value (e.g. 0..100) to a value passed to JS (e.g. -1.0..2.5).
-   * passed to JS (e.g. -1.0..2.5).
    */
   public double toRealProgress(int seekBarProgress) {
     if (seekBarProgress == getMax()) {
@@ -85,9 +91,7 @@ public class ReactSlider extends SeekBar {
     return seekBarProgress * getStepValue() + mMinValue;
   }
 
-  /**
+  /** Update underlying native SeekBar's values. */
-   * Update underlying native SeekBar's values.
-   */
   private void updateAll() {
     if (mStep == 0) {
       mStepCalculated = (mMaxValue - mMinValue) / (double) DEFAULT_TOTAL_STEPS;
@@ -96,12 +100,9 @@ public class ReactSlider extends SeekBar {
     updateValue();
   }
 
-  /**
+  /** Update value only (optimization in case only value is set). */
-   * Update value only (optimization in case only value is set).
-   */
   private void updateValue() {
-    setProgress((int) Math.round(
+    setProgress((int) Math.round((mValue - mMinValue) / (mMaxValue - mMinValue) * getTotalSteps()));
-      (mValue - mMinValue) / (mMaxValue - mMinValue) * getTotalSteps()));
   }
 
   private int getTotalSteps() {