ReactSwitch.java → Kotlin (facebook#45931)

Summary:
Pull Request resolved: facebook#45931

Migration to Kotlin.

Changelog: [Android][Changed] Migrated ReactSwitch to Kotlin

Reviewed By: cortinico

Differential Revision: D60898267

fbshipit-source-id: 530e240a071deb3eff3e463f04edc590de03c594

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/switchview/ReactSwitch.kt

@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.facebook.react.views.switchview
+
+import android.content.Context
+import android.content.res.ColorStateList
+import android.graphics.PorterDuff
+import android.graphics.PorterDuffColorFilter
+import android.graphics.drawable.ColorDrawable
+import android.graphics.drawable.Drawable
+import android.graphics.drawable.RippleDrawable
+import androidx.appcompat.widget.SwitchCompat
+
+/**
+ * Switch that has its value controlled by JS. Whenever the value of the switch changes, we do not
+ * allow any other changes to that switch until JS sets a value explicitly. This stops the Switch
+ * from changing its value multiple times, when those changes have not been processed by JS first.
+ */
+internal class ReactSwitch(context: Context) : SwitchCompat(context) {
+
+  private var allowChange = true
+  private var trackColorForFalse: Int? = null
+  private var trackColorForTrue: Int? = null
+
+  override fun setChecked(checked: Boolean) {
+    if (allowChange && isChecked != checked) {
+      allowChange = false
+      super.setChecked(checked)
+      setTrackColor(checked)
+    } else {
+      // Even if mAllowChange is set to false or the checked value hasn't changed, we still must
+      // call the super method, since it will make sure the thumb is moved back to the correct edge.
+      // Without calling the super method, the thumb might stuck in the middle of the switch.
+      super.setChecked(isChecked)
+    }
+  }
+
+  override fun setBackgroundColor(color: Int) {
+    background =
+        RippleDrawable(createRippleDrawableColorStateList(color), ColorDrawable(color), null)
+  }
+
+  public fun setColor(drawable: Drawable, color: Int?): Unit {
+    if (color == null) {
+      drawable.clearColorFilter()
+    } else {
+      drawable.setColorFilter(PorterDuffColorFilter(color, PorterDuff.Mode.MULTIPLY))
+    }
+  }
+
+  public fun setTrackColor(color: Int?): Unit {
+    setColor(super.getTrackDrawable(), color)
+  }
+
+  public fun setThumbColor(color: Int?): Unit {
+    setColor(super.getThumbDrawable(), color)
+
+    // Set the ripple color if background is instance of RippleDrawable
+    if (color != null && super.getBackground() is RippleDrawable) {
+      val customColorState = createRippleDrawableColorStateList(color)
+      (super.getBackground() as RippleDrawable).setColor(customColorState)
+    }
+  }
+
+  public fun setOn(on: Boolean): Unit {
+    // If the switch has a different value than the value sent by JS, we must change it.
+    if (isChecked != on) {
+      super.setChecked(on)
+      setTrackColor(on)
+    }
+    allowChange = true
+  }
+
+  public fun setTrackColorForTrue(color: Int?): Unit {
+    if (color == trackColorForTrue) {
+      return
+    }
+    trackColorForTrue = color
+    if (isChecked) {
+      setTrackColor(trackColorForTrue)
+    }
+  }
+
+  public fun setTrackColorForFalse(color: Int?): Unit {
+    if (color == trackColorForFalse) {
+      return
+    }
+    trackColorForFalse = color
+    if (!isChecked) {
+      setTrackColor(trackColorForFalse)
+    }
+  }
+
+  private fun setTrackColor(checked: Boolean) {
+    if (trackColorForTrue != null || trackColorForFalse != null) {
+      // Update the track color to reflect the new value. We only want to do this if these
+      // props were actually set from JS; otherwise we'll just reset the color to the default.
+      val currentTrackColor = if (checked) trackColorForTrue else trackColorForFalse
+      setTrackColor(currentTrackColor)
+    }
+  }
+
+  private fun createRippleDrawableColorStateList(color: Int): ColorStateList =
+      ColorStateList(arrayOf(intArrayOf(android.R.attr.state_pressed)), intArrayOf(color))
+}