Merge "Add task content animation property" into ub-launcher3-master
diff --git a/go/quickstep/src/com/android/quickstep/TaskAdapter.java b/go/quickstep/src/com/android/quickstep/TaskAdapter.java
index 674fcae..66c074b 100644
--- a/go/quickstep/src/com/android/quickstep/TaskAdapter.java
+++ b/go/quickstep/src/com/android/quickstep/TaskAdapter.java
@@ -94,7 +94,7 @@
             return;
         }
         Task task = tasks.get(position);
-        holder.bindTask(task);
+        holder.bindTask(task, false /* willAnimate */);
         mLoader.loadTaskIconAndLabel(task, () -> {
             // Ensure holder still has the same task.
             if (Objects.equals(task, holder.getTask())) {
@@ -110,6 +110,13 @@
     }
 
     @Override
+    public void onBindViewHolder(@NonNull TaskHolder holder, int position,
+            @NonNull List<Object> payloads) {
+        // TODO: Bind task in preparation for animation. For now, we apply UI changes immediately.
+        super.onBindViewHolder(holder, position, payloads);
+    }
+
+    @Override
     public void onViewAttachedToWindow(@NonNull TaskHolder holder) {
         if (holder.getTask() == null) {
             return;
diff --git a/go/quickstep/src/com/android/quickstep/TaskHolder.java b/go/quickstep/src/com/android/quickstep/TaskHolder.java
index 98dc989..91a3534 100644
--- a/go/quickstep/src/com/android/quickstep/TaskHolder.java
+++ b/go/quickstep/src/com/android/quickstep/TaskHolder.java
@@ -15,6 +15,9 @@
  */
 package com.android.quickstep;
 
+import android.graphics.Bitmap;
+
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.recyclerview.widget.RecyclerView.ViewHolder;
 
@@ -40,13 +43,28 @@
     }
 
     /**
-     * Bind a task to the holder, resetting the view and preparing it for content to load in.
+     * Bind the task model to the holder. This will take the current task content in the task
+     * object (i.e. icon, thumbnail, label) and either apply the content immediately or simply bind
+     * the content to animate to at a later time. If the task does not have all its content loaded,
+     * the view will prepare appropriate default placeholders and it is the callers responsibility
+     * to change them at a later time.
+     *
+     * Regardless of whether it is animating, input handlers will be bound immediately (see
+     * {@link TaskActionController}).
      *
      * @param task the task to bind to the view
+     * @param willAnimate true if UI should animate in later, false if it should apply immediately
      */
-    public void bindTask(Task task) {
+    public void bindTask(@NonNull Task task, boolean willAnimate) {
         mTask = task;
-        mTaskItemView.resetTaskItemView();
+        Bitmap thumbnail = (task.thumbnail != null) ? task.thumbnail.thumbnail : null;
+        if (willAnimate) {
+            mTaskItemView.startContentAnimation(task.icon, thumbnail, task.titleDescription);
+        } else {
+            mTaskItemView.setIcon(task.icon);
+            mTaskItemView.setThumbnail(thumbnail);
+            mTaskItemView.setLabel(task.titleDescription);
+        }
     }
 
     /**
diff --git a/go/quickstep/src/com/android/quickstep/views/TaskItemView.java b/go/quickstep/src/com/android/quickstep/views/TaskItemView.java
index 0a3fba8..a8fc78a 100644
--- a/go/quickstep/src/com/android/quickstep/views/TaskItemView.java
+++ b/go/quickstep/src/com/android/quickstep/views/TaskItemView.java
@@ -21,6 +21,7 @@
 import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.Drawable;
 import android.util.AttributeSet;
+import android.util.FloatProperty;
 import android.view.View;
 import android.widget.ImageView;
 import android.widget.LinearLayout;
@@ -39,15 +40,37 @@
     private static final String DEFAULT_LABEL = "...";
     private final Drawable mDefaultIcon;
     private final Drawable mDefaultThumbnail;
+    private final TaskLayerDrawable mIconDrawable;
+    private final TaskLayerDrawable mThumbnailDrawable;
     private TextView mLabelView;
     private ImageView mIconView;
     private ImageView mThumbnailView;
+    private float mContentTransitionProgress;
+
+    /**
+     * Property representing the content transition progress of the view. 1.0f represents that the
+     * currently bound icon, thumbnail, and label are fully animated in and visible.
+     */
+    public static FloatProperty CONTENT_TRANSITION_PROGRESS =
+            new FloatProperty<TaskItemView>("taskContentTransitionProgress") {
+                @Override
+                public void setValue(TaskItemView view, float progress) {
+                    view.setContentTransitionProgress(progress);
+                }
+
+                @Override
+                public Float get(TaskItemView view) {
+                    return view.mContentTransitionProgress;
+                }
+            };
 
     public TaskItemView(Context context, AttributeSet attrs) {
         super(context, attrs);
         Resources res = context.getResources();
         mDefaultIcon = res.getDrawable(android.R.drawable.sym_def_app_icon, context.getTheme());
         mDefaultThumbnail = res.getDrawable(R.drawable.default_thumbnail, context.getTheme());
+        mIconDrawable = new TaskLayerDrawable(context);
+        mThumbnailDrawable = new TaskLayerDrawable(context);
     }
 
     @Override
@@ -56,6 +79,12 @@
         mLabelView = findViewById(R.id.task_label);
         mThumbnailView = findViewById(R.id.task_thumbnail);
         mIconView = findViewById(R.id.task_icon);
+
+        mThumbnailView.setImageDrawable(mThumbnailDrawable);
+        mIconView.setImageDrawable(mIconDrawable);
+
+        resetTaskItemView();
+        CONTENT_TRANSITION_PROGRESS.setValue(this, 1.0f);
     }
 
     /**
@@ -74,6 +103,7 @@
      */
     public void setLabel(@Nullable String label) {
         mLabelView.setText(getSafeLabel(label));
+        // TODO: Animation for label
     }
 
     /**
@@ -86,7 +116,7 @@
         // The icon proper is actually smaller than the drawable and has "padding" on the side for
         // the purpose of drawing the shadow, allowing the icon to pop up, so we need to scale the
         // view if we want the icon to be flush with the bottom of the thumbnail.
-        mIconView.setImageDrawable(getSafeIcon(icon));
+        mIconDrawable.setCurrentDrawable(getSafeIcon(icon));
     }
 
     /**
@@ -95,13 +125,38 @@
      * @param thumbnail task thumbnail for the task
      */
     public void setThumbnail(@Nullable Bitmap thumbnail) {
-        mThumbnailView.setImageDrawable(getSafeThumbnail(thumbnail));
+        mThumbnailDrawable.setCurrentDrawable(getSafeThumbnail(thumbnail));
     }
 
     public View getThumbnailView() {
         return mThumbnailView;
     }
 
+    /**
+     * Start a new animation from the current task content to the specified new content. The caller
+     * is responsible for the actual animation control via the property
+     * {@link #CONTENT_TRANSITION_PROGRESS}.
+     *
+     * @param endIcon the icon to animate to
+     * @param endThumbnail the thumbnail to animate to
+     * @param endLabel the label to animate to
+     */
+    public void startContentAnimation(@Nullable Drawable endIcon, @Nullable Bitmap endThumbnail,
+            @Nullable String endLabel) {
+        mIconDrawable.startNewTransition(getSafeIcon(endIcon));
+        mThumbnailDrawable.startNewTransition(getSafeThumbnail(endThumbnail));
+        // TODO: Animation for label
+
+        setContentTransitionProgress(0.0f);
+    }
+
+    private void setContentTransitionProgress(float progress) {
+        mContentTransitionProgress = progress;
+        mIconDrawable.setTransitionProgress(progress);
+        mThumbnailDrawable.setTransitionProgress(progress);
+        // TODO: Animation for label
+    }
+
     private @NonNull Drawable getSafeIcon(@Nullable Drawable icon) {
         return (icon != null) ? icon : mDefaultIcon;
     }