Add spring animation for newly created desktop

spring into place from 40 dp offscreen:
expressive default spatial spring
    damping: 0.8,
    stiffness: 380

Bug: 399642211
Flag: com.android.window.flags.enable_multiple_desktops_frontend
Flag: com.android.window.flags.enable_multiple_desktops_backend
Test: create desktop and check animation
Change-Id: Ie15b4f58d394590ea24d72036a587111f1e6cf3b

quickstep/src/com/android/quickstep/views/RecentsView.java

@@ -5045,7 +5045,8 @@ public abstract class RecentsView<
      *
      * @param offsetProgress From 0 to 1 where 0 means no offset and 1 means offset offscreen.
      */
-    private float getHorizontalOffsetSize(int childIndex, int midpointIndex, float offsetProgress) {
+    protected float getHorizontalOffsetSize(int childIndex, int midpointIndex,
+            float offsetProgress) {
         if (offsetProgress == 0) {
             // Don't bother calculating everything below if we won't offset anyway.
             return 0;

quickstep/src/com/android/quickstep/views/RecentsViewUtils.kt

@@ -29,11 +29,16 @@ import android.view.View.LAYOUT_DIRECTION_LTR
 import android.view.View.LAYOUT_DIRECTION_RTL
 import androidx.core.view.children
 import androidx.core.view.isInvisible
+import androidx.dynamicanimation.animation.FloatPropertyCompat
+import androidx.dynamicanimation.animation.SpringAnimation
+import androidx.dynamicanimation.animation.SpringForce
 import com.android.launcher3.AbstractFloatingView.TYPE_TASK_MENU
 import com.android.launcher3.AbstractFloatingView.getTopOpenViewWithType
 import com.android.launcher3.Flags.enableDesktopExplodedView
 import com.android.launcher3.Flags.enableLargeDesktopWindowingTile
 import com.android.launcher3.Flags.enableOverviewOnConnectedDisplays
+import com.android.launcher3.PagedView.INVALID_PAGE
+import com.android.launcher3.R
 import com.android.launcher3.Utilities.getPivotsForScalingRectToRect
 import com.android.launcher3.statehandlers.DesktopVisibilityController
 import com.android.launcher3.statehandlers.DesktopVisibilityController.Companion.INACTIVE_DESK_ID
@@ -256,6 +261,44 @@ class RecentsViewUtils(private val recentsView: RecentsView<*, *>) : DesktopVisi
         recentsView.addDeskButton?.isInvisible = !canCreateDesks
     }
 
+    private fun animateDesktopTaskViewSpringIn(desktopTaskView: DesktopTaskView) {
+        val taskDismissFloatProperty =
+            FloatPropertyCompat.createFloatPropertyCompat(
+                desktopTaskView.primaryDismissTranslationProperty
+            )
+
+        with(recentsView) {
+            // Calculate initial translation to bring it offscreen.
+            val desktopTaskViewIndex = indexOfChild(desktopTaskView)
+            val midpointIndex =
+                if (getTaskViewAt(desktopTaskViewIndex + 1) != null) desktopTaskViewIndex + 1
+                else INVALID_PAGE
+            var offscreenTranslationX =
+                getHorizontalOffsetSize(desktopTaskViewIndex, midpointIndex, 1f)
+
+            // Add 40dp to the offscreen translation.
+            val additionalOffsetPx =
+                context.resources.getDimensionPixelSize(
+                    R.dimen.newly_created_desktop_offscreen_position
+                )
+            offscreenTranslationX += if (isRtl) additionalOffsetPx else -additionalOffsetPx
+            desktopTaskView.primaryDismissTranslationProperty.set(
+                desktopTaskView,
+                offscreenTranslationX,
+            )
+            desktopTaskView.isInvisible = false
+
+            val dampingRatio =
+                context.resources.getFloat(R.dimen.newly_created_desktop_spring_damping_ratio)
+            val stiffness =
+                context.resources.getFloat(R.dimen.newly_created_desktop_spring_stiffness)
+
+            SpringAnimation(desktopTaskView, taskDismissFloatProperty)
+                .setSpring(SpringForce(0f).setDampingRatio(dampingRatio).setStiffness(stiffness))
+                .start()
+        }
+    }
+
     override fun onDeskAdded(displayId: Int, deskId: Int) {
         with(recentsView) {
             // Ignore desk changes that don't belong to this display.
@@ -278,12 +321,14 @@ class RecentsViewUtils(private val recentsView: RecentsView<*, *>) : DesktopVisi
                 pagedViewOrientedState,
                 taskOverlayFactory,
             )
+            desktopTaskView.isInvisible = true
 
             val insertionIndex = 1 + indexOfChild(addDeskButton!!)
             addView(desktopTaskView, insertionIndex)
             updateTaskSize()
             updateChildTaskOrientations()
             updateScrollSynchronously()
+            animateDesktopTaskViewSpringIn(desktopTaskView)
 
             // Set Current Page based on the stored TaskView.
             currentTaskView?.let { setCurrentPage(indexOfChild(it)) }