Merge "Add task layer drawable class for Recents Go." into ub-launcher3-qt-dev
diff --git a/go/quickstep/res/drawable/empty_content_box.xml b/go/quickstep/res/drawable/empty_content_box.xml
new file mode 100644
index 0000000..a488388
--- /dev/null
+++ b/go/quickstep/res/drawable/empty_content_box.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+ Copyright (C) 2019 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.
+-->
+<shape
+ xmlns:android="http://schemas.android.com/apk/res/android"
+ android:shape="rectangle">
+ <solid android:color="@android:color/transparent"/>
+ <stroke android:color="@android:color/white" android:width="4px"/>
+ <corners android:radius="2dp"/>
+</shape>
\ No newline at end of file
diff --git a/go/quickstep/src/com/android/quickstep/views/TaskLayerDrawable.java b/go/quickstep/src/com/android/quickstep/views/TaskLayerDrawable.java
new file mode 100644
index 0000000..3a23048
--- /dev/null
+++ b/go/quickstep/src/com/android/quickstep/views/TaskLayerDrawable.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2019 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.quickstep.views;
+
+import android.content.Context;
+import android.graphics.drawable.Drawable;
+import android.graphics.drawable.LayerDrawable;
+
+import androidx.annotation.NonNull;
+
+import com.android.launcher3.R;
+
+/**
+ * A layer drawable for task content that transitions between two drawables by crossfading. Similar
+ * to {@link android.graphics.drawable.TransitionDrawable} but allows callers to control transition
+ * progress and provides a default, empty drawable.
+ */
+public final class TaskLayerDrawable extends LayerDrawable {
+ private final Drawable mEmptyDrawable;
+
+ public TaskLayerDrawable(Context context) {
+ super(new Drawable[0]);
+
+ // Use empty drawable for both layers initially.
+ mEmptyDrawable = context.getResources().getDrawable(
+ R.drawable.empty_content_box, context.getTheme());
+ addLayer(mEmptyDrawable);
+ addLayer(mEmptyDrawable);
+ setTransitionProgress(1.0f);
+ }
+
+ /**
+ * Immediately set the front-most drawable layer.
+ *
+ * @param drawable drawable to set
+ */
+ public void setCurrentDrawable(@NonNull Drawable drawable) {
+ setDrawable(0, drawable);
+ }
+
+ /**
+ * Immediately reset the drawable to showing the empty drawable.
+ */
+ public void resetDrawable() {
+ setCurrentDrawable(mEmptyDrawable);
+ }
+
+ /**
+ * Prepare to start animating the transition by pushing the current drawable to the back and
+ * setting a new drawable to the front layer and making it invisible.
+ *
+ * @param endDrawable drawable to animate to
+ */
+ public void startNewTransition(@NonNull Drawable endDrawable) {
+ Drawable oldDrawable = getDrawable(0);
+ setDrawable(1, oldDrawable);
+ setDrawable(0, endDrawable);
+ setTransitionProgress(0.0f);
+ }
+
+ /**
+ * Set the progress of the transition animation to crossfade the two drawables.
+ *
+ * @param progress current transition progress between 0 (front view invisible) and 1
+ * (front view visible)
+ */
+ public void setTransitionProgress(float progress) {
+ if (progress > 1 || progress < 0) {
+ throw new IllegalArgumentException("Transition progress should be between 0 and 1");
+ }
+ int drawableAlpha = (int) (progress * 255);
+ getDrawable(0).setAlpha(drawableAlpha);
+ getDrawable(1).setAlpha(255 - drawableAlpha);
+ invalidateSelf();
+ }
+}