Add the KeyboardQuickSwitchView (2/2)

Adding KeyboardQuickSwitchView and associated flows.

Test: Manually tested alt-tab and alt-shift-tab in and out of overview on a tablet and phone
Bug: 258854035
Change-Id: Ifb48b005067b3a9c66acfd5ecdbae144b359d3be

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

@@ -0,0 +1,192 @@
+/*
+ * Copyright (C) 2023 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 android.content.ComponentName;
+import android.content.pm.ActivityInfo;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.android.launcher3.R;
+import com.android.launcher3.taskbar.overlay.TaskbarOverlayContext;
+import com.android.quickstep.RecentsModel;
+import com.android.quickstep.util.GroupTask;
+import com.android.systemui.shared.recents.model.Task;
+import com.android.systemui.shared.recents.model.ThumbnailData;
+
+import java.io.PrintWriter;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.function.Consumer;
+import java.util.stream.Collectors;
+
+/**
+ * Handles initialization of the {@link KeyboardQuickSwitchViewController}.
+ */
+public final class KeyboardQuickSwitchController implements
+        TaskbarControllers.LoggableTaskbarController {
+
+    static final int MAX_TASKS = 6;
+
+    @NonNull private final ControllerCallbacks mControllerCallbacks = new ControllerCallbacks();
+
+    // Initialized on init
+    @Nullable private RecentsModel mModel;
+
+    // Used to keep track of the last requested task list id, so that we do not request to load the
+    // tasks again if we have already requested it and the task list has not changed
+    private int mTaskListChangeId = -1;
+    // Only empty before the recent tasks list has been loaded the first time
+    @NonNull private List<GroupTask> mTasks = new ArrayList<>();
+    private int mNumHiddenTasks = 0;
+
+    // Initialized in init
+    private TaskbarControllers mControllers;
+
+    @Nullable private KeyboardQuickSwitchViewController mQuickSwitchViewController;
+
+    /** Initialize the controller. */
+    public void init(@NonNull TaskbarControllers controllers) {
+        mControllers = controllers;
+        mModel = RecentsModel.INSTANCE.get(controllers.taskbarActivityContext);
+    }
+
+    void onConfigurationChanged(@ActivityInfo.Config int configChanges) {
+        if (mQuickSwitchViewController == null) {
+            return;
+        }
+        if ((configChanges & (ActivityInfo.CONFIG_KEYBOARD
+                | ActivityInfo.CONFIG_KEYBOARD_HIDDEN)) != 0) {
+            mQuickSwitchViewController.closeQuickSwitchView(true);
+            return;
+        }
+        int currentFocusedIndex = mQuickSwitchViewController.getCurrentFocusedIndex();
+        onDestroy();
+        if (currentFocusedIndex != -1) {
+            mControllers.taskbarActivityContext.getMainThreadHandler().post(
+                    () -> openQuickSwitchView(currentFocusedIndex));
+        }
+    }
+
+    void openQuickSwitchView() {
+        openQuickSwitchView(-1);
+    }
+
+    private void openQuickSwitchView(int currentFocusedIndex) {
+        if (mQuickSwitchViewController != null) {
+            return;
+        }
+        TaskbarOverlayContext overlayContext =
+                mControllers.taskbarOverlayController.requestWindow();
+        KeyboardQuickSwitchView keyboardQuickSwitchView =
+                (KeyboardQuickSwitchView) overlayContext.getLayoutInflater()
+                        .inflate(
+                                R.layout.keyboard_quick_switch_view,
+                                overlayContext.getDragLayer(),
+                                /* attachToRoot= */ false);
+        mQuickSwitchViewController = new KeyboardQuickSwitchViewController(
+                mControllers, overlayContext, keyboardQuickSwitchView, mControllerCallbacks);
+
+        if (mModel.isTaskListValid(mTaskListChangeId)) {
+            mQuickSwitchViewController.openQuickSwitchView(
+                    mTasks, mNumHiddenTasks, /* updateTasks= */ false, currentFocusedIndex);
+            return;
+        }
+        mTaskListChangeId = mModel.getTasks((tasks) -> {
+            // Only store MAX_TASK tasks, from most to least recent
+            Collections.reverse(tasks);
+            mTasks = tasks.stream().limit(MAX_TASKS).collect(Collectors.toList());
+            mNumHiddenTasks = Math.max(0, tasks.size() - MAX_TASKS);
+            mQuickSwitchViewController.openQuickSwitchView(
+                    mTasks, mNumHiddenTasks, /* updateTasks= */ true, currentFocusedIndex);
+        });
+    }
+
+    void closeQuickSwitchView() {
+        if (mQuickSwitchViewController == null) {
+            return;
+        }
+        mQuickSwitchViewController.closeQuickSwitchView(true);
+    }
+
+    /**
+     * See {@link TaskbarUIController#launchFocusedTask()}
+     */
+    int launchFocusedTask() {
+        // Return -1 so that the RecentsView is not incorrectly opened when the user closes the
+        // quick switch view by tapping the screen.
+        return mQuickSwitchViewController == null
+                ? -1 : mQuickSwitchViewController.launchFocusedTask();
+    }
+
+    void onDestroy() {
+        if (mQuickSwitchViewController != null) {
+            mQuickSwitchViewController.onDestroy();
+        }
+    }
+
+    @Override
+    public void dumpLogs(String prefix, PrintWriter pw) {
+        pw.println(prefix + "KeyboardQuickSwitchController:");
+
+        pw.println(prefix + "\tisOpen=" + (mQuickSwitchViewController != null));
+        pw.println(prefix + "\tmNumHiddenTasks=" + mNumHiddenTasks);
+        pw.println(prefix + "\tmTaskListChangeId=" + mTaskListChangeId);
+        pw.println(prefix + "\tmTasks=[");
+        for (GroupTask task : mTasks) {
+            Task task1 = task.task1;
+            Task task2 = task.task2;
+            ComponentName cn1 = task1.getTopComponent();
+            ComponentName cn2 = task2 != null ? task2.getTopComponent() : null;
+            pw.println(prefix + "\t\tt1: (id=" + task1.key.id
+                    + "; package=" + (cn1 != null ? cn1.getPackageName() + ")" : "no package)")
+                    + " t2: (id=" + (task2 != null ? task2.key.id : "-1")
+                    + "; package=" + (cn2 != null ? cn2.getPackageName() + ")"
+                    : "no package)"));
+        }
+        pw.println(prefix + "\t]");
+
+        if (mQuickSwitchViewController != null) {
+            mQuickSwitchViewController.dumpLogs(prefix + '\t', pw);
+        }
+    }
+
+    class ControllerCallbacks {
+
+        int getTaskCount() {
+            return mNumHiddenTasks == 0 ? mTasks.size() : MAX_TASKS + 1;
+        }
+
+        @Nullable
+        GroupTask getTaskAt(int index) {
+            return index < 0 || index >= mTasks.size() ? null : mTasks.get(index);
+        }
+
+        void updateThumbnailInBackground(Task task, Consumer<ThumbnailData> callback) {
+            mModel.getThumbnailCache().updateThumbnailInBackground(task, callback);
+        }
+
+        void updateTitleInBackground(Task task, Consumer<Task> callback) {
+            mModel.getIconCache().updateIconInBackground(task, callback);
+        }
+
+        void onCloseComplete() {
+            mQuickSwitchViewController = null;
+        }
+    }
+}