Remove MaterialContainerTransition. Long live MaterialContainerTransform.

Author: nickbutcher

Owl/app/src/main/java/com/materialstudies/owl/ui/featured/FeaturedFragment.kt

@@ -24,6 +24,7 @@ import androidx.core.view.doOnNextLayout
 import androidx.fragment.app.Fragment
 import androidx.navigation.findNavController
 import androidx.navigation.fragment.FragmentNavigatorExtras
+import com.google.android.material.transition.Hold
 import com.materialstudies.owl.databinding.FragmentFeaturedBinding
 import com.materialstudies.owl.model.CourseId
 import com.materialstudies.owl.model.courses
@@ -47,17 +48,16 @@ class FeaturedFragment : Fragment() {
                         view to "shared_element"
                     )
                     val action = FeaturedFragmentDirections.actionFeaturedToLearn(courseId)
-                    /* awaiting aosp/987385 in fragment 1.2.0-alpha02
-                    exitTransition = Recede().apply {
+                    exitTransition = Hold().apply {
                         addTarget(root)
                         excludeTarget(view, true)
-                    duration = 300L
-                    }*/
+                        duration = 300L
+                    }
                     view.findNavController().navigate(action, extras)
                 }
             }
             featuredGrid.apply {
-                itemAnimator = SpringAddItemAnimator()
+                //itemAnimator = SpringAddItemAnimator()
                 adapter = FeaturedAdapter(onClick).apply {
                     // add data after layout so that animations run
                     doOnNextLayout {

Owl/app/src/main/java/com/materialstudies/owl/ui/learn/LearnFragment.kt

@@ -24,14 +24,17 @@ import android.view.animation.AnimationUtils
 import androidx.fragment.app.Fragment
 import androidx.navigation.fragment.findNavController
 import androidx.navigation.fragment.navArgs
+import com.google.android.material.transition.MaterialArcMotion
+import com.google.android.material.transition.MaterialContainerTransform
+import com.google.android.material.transition.MaterialContainerTransform.FADE_MODE_THROUGH
 import com.materialstudies.owl.R
 import com.materialstudies.owl.databinding.FragmentLearnBinding
 import com.materialstudies.owl.model.CourseRepo
 import com.materialstudies.owl.model.courses
 import com.materialstudies.owl.ui.lessons.LessonsSheetFragment
-import com.materialstudies.owl.util.transition.DiagonalSlide
-import com.materialstudies.owl.util.transition.MaterialContainerTransition
 import com.materialstudies.owl.util.loadListener
+import com.materialstudies.owl.util.themeColor
+import com.materialstudies.owl.util.transition.DiagonalSlide
 import java.util.concurrent.TimeUnit
 
 /**
@@ -67,7 +70,12 @@ class LearnFragment : Fragment() {
             context,
             android.R.interpolator.fast_out_slow_in
         )
-        sharedElementEnterTransition = MaterialContainerTransition(R.id.scroll).apply {
+        val containerColor = requireContext().themeColor(R.attr.colorSurface)
+        sharedElementEnterTransition = MaterialContainerTransform(requireContext()).apply {
+            drawingViewId = R.id.nav_host
+            this.containerColor = containerColor
+            pathMotion = MaterialArcMotion()
+            fadeMode = FADE_MODE_THROUGH
             duration = 400L
             interpolator = interp
         }
@@ -77,7 +85,11 @@ class LearnFragment : Fragment() {
             duration = 200L
             interpolator = interp
         }
-        sharedElementReturnTransition = MaterialContainerTransition().apply {
+        sharedElementReturnTransition = MaterialContainerTransform(requireContext()).apply {
+            drawingViewId = R.id.nav_host
+            fadeMode = FADE_MODE_THROUGH
+            this.containerColor = containerColor
+            pathMotion = MaterialArcMotion()
             duration = 300L
             interpolator = interp
         }

Owl/app/src/main/java/com/materialstudies/owl/ui/mycourses/MyCoursesFragment.kt

@@ -22,6 +22,7 @@ import androidx.annotation.Px
 import androidx.core.view.doOnNextLayout
 import androidx.fragment.app.Fragment
 import androidx.recyclerview.widget.RecyclerView
+import com.google.android.material.transition.Hold
 import com.materialstudies.owl.R
 import com.materialstudies.owl.databinding.FragmentMyCoursesBinding
 import com.materialstudies.owl.model.courses
@@ -37,7 +38,7 @@ class MyCoursesFragment : Fragment() {
     ): View {
         val binding = FragmentMyCoursesBinding.inflate(inflater, container, false).apply {
             list.apply {
-                itemAnimator = SpringAddItemAnimator()
+                //itemAnimator = SpringAddItemAnimator()
                 addItemDecoration(
                     BottomSpacingItemDecoration(resources.getDimensionPixelSize(R.dimen.grid_2))
                 )
@@ -53,6 +54,7 @@ class MyCoursesFragment : Fragment() {
             }
         }
         postponeEnterTransition(1000L, TimeUnit.MILLISECONDS)
+        exitTransition = Hold()
         return binding.root
     }
 }

Owl/app/src/main/java/com/materialstudies/owl/util/ViewExtensions.kt

@@ -18,27 +18,19 @@ package com.materialstudies.owl.util
 
 import android.animation.ValueAnimator
 import android.content.Context
-import android.graphics.Bitmap
-import android.graphics.Bitmap.Config.ARGB_8888
 import android.graphics.Color
 import android.graphics.drawable.BitmapDrawable
 import android.graphics.drawable.ColorDrawable
 import android.view.View
-import android.view.View.GONE
-import android.view.View.MeasureSpec
-import android.view.View.VISIBLE
+import android.view.View.*
 import android.view.ViewGroup
 import android.view.animation.AnimationUtils
 import androidx.annotation.AttrRes
 import androidx.annotation.ColorInt
 import androidx.annotation.IdRes
-import androidx.annotation.Px
 import androidx.core.animation.doOnEnd
 import androidx.core.content.res.use
-import androidx.core.graphics.applyCanvas
-import androidx.core.view.ViewCompat
 import androidx.core.view.drawToBitmap
-import androidx.core.view.forEach
 import androidx.dynamicanimation.animation.DynamicAnimation.ViewProperty
 import androidx.dynamicanimation.animation.SpringAnimation
 import androidx.dynamicanimation.animation.SpringForce
@@ -108,42 +100,6 @@ fun Context.themeColor(
     }
 }
 
-/**
- * Search this view and any children for a [ColorDrawable] `background` and return it's `color`,
- * else return `colorSurface`.
- */
-@ColorInt
-fun View.descendantBackgroundColor(): Int {
-    val bg = backgroundColor()
-    if (bg != null) {
-        return bg
-    } else if (this is ViewGroup) {
-        forEach {
-            val childBg = descendantBackgroundColorOrNull()
-            if (childBg != null) {
-                return childBg
-            }
-        }
-    }
-    return context.themeColor(android.R.attr.colorBackground)
-}
-
-@ColorInt
-private fun View.descendantBackgroundColorOrNull(): Int? {
-    val bg = backgroundColor()
-    if (bg != null) {
-        return bg
-    } else if (this is ViewGroup) {
-        forEach {
-            val childBg = backgroundColor()
-            if (childBg != null) {
-                return childBg
-            }
-        }
-    }
-    return null
-}
-
 /**
  * Check if this [View]'s `background` is a [ColorDrawable] and if so, return it's `color`,
  * otherwise `null`.
@@ -157,17 +113,6 @@ fun View.backgroundColor(): Int? {
     return null
 }
 
-/**
- * Walk up from a [View] looking for an ancestor with a given `id`.
- */
-fun View.findAncestorById(@IdRes ancestorId: Int): View {
-    return when {
-        id == ancestorId -> this
-        parent is View -> (parent as View).findAncestorById(ancestorId)
-        else -> throw IllegalArgumentException("$ancestorId not a valid ancestor")
-    }
-}
-
 /**
  * Potentially animate showing a [BottomNavigationView].
  *
@@ -247,18 +192,3 @@ fun BottomNavigationView.hide() {
         start()
     }
 }
-
-/**
- * A copy of the KTX method, adding the ability to add extra padding the bottom of the [Bitmap];
- * useful when it will be used in a [android.graphics.BitmapShader][BitmapShader] with
- * a [android.graphics.Shader.TileMode.CLAMP][CLAMP tile mode].
- */
-fun View.drawToBitmap(@Px extraPaddingBottom: Int = 0): Bitmap {
-    if (!ViewCompat.isLaidOut(this)) {
-        throw IllegalStateException("View needs to be laid out before calling drawToBitmap()")
-    }
-    return Bitmap.createBitmap(width, height + extraPaddingBottom, ARGB_8888).applyCanvas {
-        translate(-scrollX.toFloat(), -scrollY.toFloat())
-        draw(this)
-    }
-}

Owl/app/src/main/java/com/materialstudies/owl/util/transition/DiagonalSlide.kt

@@ -18,11 +18,11 @@ package com.materialstudies.owl.util.transition
 
 import android.animation.ObjectAnimator
 import android.animation.PropertyValuesHolder
+import android.transition.TransitionValues
+import android.transition.Visibility
 import android.view.View
 import android.view.ViewGroup
 import androidx.core.animation.doOnEnd
-import androidx.transition.TransitionValues
-import androidx.transition.Visibility
 
 /**
  * A [androidx.transition.Transition] which animates visibility changes by sliding in/out diagonally