Merge "Animate changes between action icons." into 24D1-dev am: 6610b19405

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/27196797

Change-Id: I95faa93346c7e7c3541ad65090aa6cbacf9263a8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/packages/SystemUI/src/com/android/systemui/screenshot/ui/TransitioningIconDrawable.kt b/packages/SystemUI/src/com/android/systemui/screenshot/ui/TransitioningIconDrawable.kt
new file mode 100644
index 0000000..0bc280c
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/screenshot/ui/TransitioningIconDrawable.kt
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.screenshot.ui
+
+import android.animation.ValueAnimator
+import android.content.res.ColorStateList
+import android.graphics.Canvas
+import android.graphics.ColorFilter
+import android.graphics.drawable.Drawable
+import androidx.core.animation.doOnEnd
+import java.util.Objects
+
+/**  */
+class TransitioningIconDrawable : Drawable() {
+    // The drawable for the current icon of this view. During icon transitions, this is the one
+    // being animated out.
+    private var drawable: Drawable? = null
+
+    // The incoming new icon. Only populated during transition animations (when drawable is also
+    // non-null).
+    private var enteringDrawable: Drawable? = null
+    private var colorFilter: ColorFilter? = null
+    private var tint: ColorStateList? = null
+    private var alpha = 255
+
+    private var transitionAnimator =
+        ValueAnimator.ofFloat(0f, 1f).also { it.doOnEnd { onTransitionComplete() } }
+
+    /**
+     * Set the drawable to be displayed, potentially animating the transition from one icon to the
+     * next.
+     */
+    fun setIcon(incomingDrawable: Drawable?) {
+        if (Objects.equals(drawable, incomingDrawable) && !transitionAnimator.isRunning) {
+            return
+        }
+
+        incomingDrawable?.colorFilter = colorFilter
+        incomingDrawable?.setTintList(tint)
+
+        if (drawable == null) {
+            // No existing icon drawn, just show the new one without a transition
+            drawable = incomingDrawable
+            invalidateSelf()
+            return
+        }
+
+        if (enteringDrawable != null) {
+            // There's already an entrance animation happening, just update the entering icon, not
+            // maintaining a queue or anything.
+            enteringDrawable = incomingDrawable
+            return
+        }
+
+        // There was already an icon, need to animate between icons.
+        enteringDrawable = incomingDrawable
+        transitionAnimator.setCurrentFraction(0f)
+        transitionAnimator.start()
+        invalidateSelf()
+    }
+
+    override fun draw(canvas: Canvas) {
+        // Scale the old one down, scale the new one up.
+        drawable?.let {
+            val scale =
+                if (transitionAnimator.isRunning) {
+                    1f - transitionAnimator.animatedFraction
+                } else {
+                    1f
+                }
+            drawScaledDrawable(it, canvas, scale)
+        }
+        enteringDrawable?.let {
+            val scale = transitionAnimator.animatedFraction
+            drawScaledDrawable(it, canvas, scale)
+        }
+
+        if (transitionAnimator.isRunning) {
+            invalidateSelf()
+        }
+    }
+
+    private fun drawScaledDrawable(drawable: Drawable, canvas: Canvas, scale: Float) {
+        drawable.bounds = getBounds()
+        canvas.save()
+        canvas.scale(
+            scale,
+            scale,
+            (drawable.intrinsicWidth / 2).toFloat(),
+            (drawable.intrinsicHeight / 2).toFloat()
+        )
+        drawable.draw(canvas)
+        canvas.restore()
+    }
+
+    private fun onTransitionComplete() {
+        drawable = enteringDrawable
+        enteringDrawable = null
+        invalidateSelf()
+    }
+
+    override fun setTintList(tint: ColorStateList?) {
+        super.setTintList(tint)
+        drawable?.setTintList(tint)
+        enteringDrawable?.setTintList(tint)
+        this.tint = tint
+    }
+
+    override fun setAlpha(alpha: Int) {
+        this.alpha = alpha
+    }
+
+    override fun setColorFilter(colorFilter: ColorFilter?) {
+        this.colorFilter = colorFilter
+        drawable?.colorFilter = colorFilter
+        enteringDrawable?.colorFilter = colorFilter
+    }
+
+    override fun getOpacity(): Int = alpha
+}
diff --git a/packages/SystemUI/src/com/android/systemui/screenshot/ui/binder/ActionButtonViewBinder.kt b/packages/SystemUI/src/com/android/systemui/screenshot/ui/binder/ActionButtonViewBinder.kt
index 3c5a0ec..750bd53 100644
--- a/packages/SystemUI/src/com/android/systemui/screenshot/ui/binder/ActionButtonViewBinder.kt
+++ b/packages/SystemUI/src/com/android/systemui/screenshot/ui/binder/ActionButtonViewBinder.kt
@@ -21,6 +21,7 @@
 import android.widget.LinearLayout
 import android.widget.TextView
 import com.android.systemui.res.R
+import com.android.systemui.screenshot.ui.TransitioningIconDrawable
 import com.android.systemui.screenshot.ui.viewmodel.ActionButtonViewModel
 
 object ActionButtonViewBinder {
@@ -28,7 +29,13 @@
     fun bind(view: View, viewModel: ActionButtonViewModel) {
         val iconView = view.requireViewById<ImageView>(R.id.overlay_action_chip_icon)
         val textView = view.requireViewById<TextView>(R.id.overlay_action_chip_text)
-        iconView.setImageDrawable(viewModel.appearance.icon)
+        if (iconView.drawable == null) {
+            iconView.setImageDrawable(TransitioningIconDrawable())
+        }
+        val drawable = iconView.drawable as? TransitioningIconDrawable
+        // Note we never re-bind a view to a different ActionButtonViewModel, different view
+        // models would remove/create separate views.
+        drawable?.setIcon(viewModel.appearance.icon)
         textView.text = viewModel.appearance.label
         setMargins(iconView, textView, viewModel.appearance.label?.isNotEmpty() ?: false)
         if (viewModel.onClicked != null) {