Reorganize taskbar controllers

Organize existing properties as follows:
- TaskbarViewController contains properties affecting TaskbarView (though child icons are still supplied by TaskbarHotseatController)
- TaskbarDragLayerController contains properties related to TaskbarDragLayer itself
- Renamed NavbarButtonUiController to NavbarButtonsViewController, following the pattern of TaskbarViewController and TaskbarDragLayerController
- TaskbarControllers contains the different controllers to make it easier to construct, initialize, destroy, and pass them around
- Removed TaskbarIconController as its responsibilities were moved to more specific controllers

Test: compiles and runs, manually tested
Bug: 187353581
Change-Id: Idccd95d47117101bf9617e5532a5b87635d2b8f6

quickstep/src/com/android/launcher3/taskbar/TaskbarDragLayerController.java

@@ -0,0 +1,137 @@
+/*
+ * Copyright (C) 2021 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.launcher3.taskbar;
+
+import static com.android.launcher3.AbstractFloatingView.TYPE_ALL;
+import static com.android.systemui.shared.system.ViewTreeObserverWrapper.InsetsInfo.TOUCHABLE_INSETS_FRAME;
+import static com.android.systemui.shared.system.ViewTreeObserverWrapper.InsetsInfo.TOUCHABLE_INSETS_REGION;
+
+import android.content.res.Resources;
+import android.graphics.Rect;
+
+import com.android.launcher3.AbstractFloatingView;
+import com.android.launcher3.R;
+import com.android.launcher3.anim.AlphaUpdateListener;
+import com.android.quickstep.AnimatedFloat;
+import com.android.systemui.shared.system.ViewTreeObserverWrapper.InsetsInfo;
+
+/**
+ * Handles properties/data collection, then passes the results to TaskbarDragLayer to render.
+ */
+public class TaskbarDragLayerController {
+
+    private final TaskbarActivityContext mActivity;
+    private final TaskbarDragLayer mTaskbarDragLayer;
+    private final int mFolderMargin;
+    // Alpha properties for taskbar background.
+    private final AnimatedFloat mBgTaskbar = new AnimatedFloat(this::updateBackgroundAlpha);
+    private final AnimatedFloat mBgNavbar = new AnimatedFloat(this::updateBackgroundAlpha);
+
+    // Initialized in init.
+    private TaskbarControllers mControllers;
+
+    public TaskbarDragLayerController(TaskbarActivityContext activity,
+            TaskbarDragLayer taskbarDragLayer) {
+        mActivity = activity;
+        mTaskbarDragLayer = taskbarDragLayer;
+        final Resources resources = mTaskbarDragLayer.getResources();
+        mFolderMargin = resources.getDimensionPixelSize(R.dimen.taskbar_folder_margin);
+    }
+
+    public void init(TaskbarControllers controllers) {
+        mControllers = controllers;
+        mTaskbarDragLayer.init(new TaskbarDragLayerCallbacks());
+    }
+
+    public void onDestroy() {
+        mTaskbarDragLayer.onDestroy();
+    }
+
+    /**
+     * @return Bounds (in TaskbarDragLayer coordinates) where an opened Folder can display.
+     */
+    public Rect getFolderBoundingBox() {
+        Rect boundingBox = new Rect(0, 0, mTaskbarDragLayer.getWidth(),
+                mTaskbarDragLayer.getHeight() - mActivity.getDeviceProfile().taskbarSize);
+        boundingBox.inset(mFolderMargin, mFolderMargin);
+        return boundingBox;
+    }
+
+    public AnimatedFloat getTaskbarBackgroundAlpha() {
+        return mBgTaskbar;
+    }
+
+    public AnimatedFloat getNavbarBackgroundAlpha() {
+        return mBgNavbar;
+    }
+
+    private void updateBackgroundAlpha() {
+        mTaskbarDragLayer.setTaskbarBackgroundAlpha(Math.max(mBgNavbar.value, mBgTaskbar.value));
+    }
+
+    /**
+     * Callbacks for {@link TaskbarDragLayer} to interact with its controller.
+     */
+    public class TaskbarDragLayerCallbacks {
+
+        /**
+         * Called to update the touchable insets.
+         * @see InsetsInfo#setTouchableInsets(int)
+         */
+        public void updateInsetsTouchability(InsetsInfo insetsInfo) {
+            insetsInfo.touchableRegion.setEmpty();
+            if (mTaskbarDragLayer.getAlpha() < AlphaUpdateListener.ALPHA_CUTOFF_THRESHOLD) {
+                // Let touches pass through us.
+                insetsInfo.setTouchableInsets(TOUCHABLE_INSETS_REGION);
+            } else if (mControllers.navbarButtonsViewController.isImeVisible()) {
+                insetsInfo.setTouchableInsets(TOUCHABLE_INSETS_FRAME);
+            } else if (!mControllers.uiController.isTaskbarTouchable()) {
+                // Let touches pass through us.
+                insetsInfo.setTouchableInsets(TOUCHABLE_INSETS_REGION);
+            } else if (mControllers.taskbarViewController.areIconsVisible()) {
+                // Buttons are visible, take over the full taskbar area
+                insetsInfo.setTouchableInsets(TOUCHABLE_INSETS_FRAME);
+            } else {
+                mControllers.navbarButtonsViewController.addVisibleButtonsRegion(
+                        mTaskbarDragLayer, insetsInfo.touchableRegion);
+                insetsInfo.setTouchableInsets(TOUCHABLE_INSETS_REGION);
+            }
+        }
+
+        /**
+         * Called to update the {@link InsetsInfo#contentInsets}.
+         */
+        public void updateContentInsets(Rect outContentInsets) {
+            mControllers.uiController.updateContentInsets(outContentInsets);
+        }
+
+        /**
+         * Called when a child is removed from TaskbarDragLayer.
+         */
+        public void onDragLayerViewRemoved() {
+            if (AbstractFloatingView.getOpenView(mActivity, TYPE_ALL) == null) {
+                mActivity.setTaskbarWindowFullscreen(false);
+            }
+        }
+
+        /**
+         * Returns how tall the background should be drawn at the bottom of the screen.
+         */
+        public int getTaskbarBackgroundHeight() {
+            return mActivity.getDeviceProfile().taskbarSize;
+        }
+    }
+}