Refactor LauncherAccessibilityDelegate so it can be used outside of Launcher

Bug: 198438631
Test: used talkback on launcher
Change-Id: I991320184ad93816c4ba21fb8fcfe12202bfae25

src/com/android/launcher3/accessibility/BaseAccessibilityDelegate.java

@@ -0,0 +1,192 @@
+/*
+ * 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.accessibility;
+
+import android.content.Context;
+import android.graphics.Rect;
+import android.os.Bundle;
+import android.text.TextUtils;
+import android.util.SparseArray;
+import android.view.View;
+import android.view.accessibility.AccessibilityNodeInfo;
+
+import com.android.launcher3.DropTarget;
+import com.android.launcher3.LauncherSettings;
+import com.android.launcher3.dragndrop.DragController;
+import com.android.launcher3.dragndrop.DragOptions;
+import com.android.launcher3.model.data.FolderInfo;
+import com.android.launcher3.model.data.ItemInfo;
+import com.android.launcher3.model.data.LauncherAppWidgetInfo;
+import com.android.launcher3.model.data.WorkspaceItemInfo;
+import com.android.launcher3.popup.PopupContainerWithArrow;
+import com.android.launcher3.util.Thunk;
+import com.android.launcher3.views.ActivityContext;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public abstract class BaseAccessibilityDelegate<T extends Context & ActivityContext>
+        extends View.AccessibilityDelegate implements DragController.DragListener {
+
+    public enum DragType {
+        ICON,
+        FOLDER,
+        WIDGET
+    }
+
+    public static class DragInfo {
+        public DragType dragType;
+        public ItemInfo info;
+        public View item;
+    }
+
+    protected final SparseArray<LauncherAction> mActions = new SparseArray<>();
+    protected final T mContext;
+
+    protected DragInfo mDragInfo = null;
+
+    protected BaseAccessibilityDelegate(T context) {
+        mContext = context;
+    }
+
+    @Override
+    public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfo info) {
+        super.onInitializeAccessibilityNodeInfo(host, info);
+        if (host.getTag() instanceof ItemInfo) {
+            ItemInfo item = (ItemInfo) host.getTag();
+
+            List<LauncherAction> actions = new ArrayList<>();
+            getSupportedActions(host, item, actions);
+            actions.forEach(la -> info.addAction(la.accessibilityAction));
+
+            if (!itemSupportsLongClick(host, item)) {
+                info.setLongClickable(false);
+                info.removeAction(AccessibilityNodeInfo.AccessibilityAction.ACTION_LONG_CLICK);
+            }
+        }
+    }
+
+    /**
+     * Adds all the accessibility actions that can be handled.
+     */
+    protected abstract void getSupportedActions(View host, ItemInfo item, List<LauncherAction> out);
+
+    private boolean itemSupportsLongClick(View host, ItemInfo info) {
+        return PopupContainerWithArrow.canShow(host, info);
+    }
+
+    protected boolean itemSupportsAccessibleDrag(ItemInfo item) {
+        if (item instanceof WorkspaceItemInfo) {
+            // Support the action unless the item is in a context menu.
+            return item.screenId >= 0
+                    && item.container != LauncherSettings.Favorites.CONTAINER_HOTSEAT_PREDICTION;
+        }
+        return (item instanceof LauncherAppWidgetInfo)
+                || (item instanceof FolderInfo);
+    }
+
+    @Override
+    public boolean performAccessibilityAction(View host, int action, Bundle args) {
+        if ((host.getTag() instanceof ItemInfo)
+                && performAction(host, (ItemInfo) host.getTag(), action, false)) {
+            return true;
+        }
+        return super.performAccessibilityAction(host, action, args);
+    }
+
+    protected abstract boolean performAction(
+            View host, ItemInfo item, int action, boolean fromKeyboard);
+
+    @Thunk
+    protected void announceConfirmation(String confirmation) {
+        mContext.getDragLayer().announceForAccessibility(confirmation);
+
+    }
+
+    public boolean isInAccessibleDrag() {
+        return mDragInfo != null;
+    }
+
+    public DragInfo getDragInfo() {
+        return mDragInfo;
+    }
+
+    /**
+     * @param clickedTarget the actual view that was clicked
+     * @param dropLocation relative to {@param clickedTarget}. If provided, its center is used
+     * as the actual drop location otherwise the views center is used.
+     */
+    public void handleAccessibleDrop(View clickedTarget, Rect dropLocation,
+            String confirmation) {
+        if (!isInAccessibleDrag()) return;
+
+        int[] loc = new int[2];
+        if (dropLocation == null) {
+            loc[0] = clickedTarget.getWidth() / 2;
+            loc[1] = clickedTarget.getHeight() / 2;
+        } else {
+            loc[0] = dropLocation.centerX();
+            loc[1] = dropLocation.centerY();
+        }
+
+        mContext.getDragLayer().getDescendantCoordRelativeToSelf(clickedTarget, loc);
+        mContext.getDragController().completeAccessibleDrag(loc);
+
+        if (!TextUtils.isEmpty(confirmation)) {
+            announceConfirmation(confirmation);
+        }
+    }
+
+    protected abstract boolean beginAccessibleDrag(View item, ItemInfo info, boolean fromKeyboard);
+
+
+    @Override
+    public void onDragEnd() {
+        mContext.getDragController().removeDragListener(this);
+        mDragInfo = null;
+    }
+
+    @Override
+    public void onDragStart(DropTarget.DragObject dragObject, DragOptions options) {
+        // No-op
+    }
+
+    public class LauncherAction {
+        public final int keyCode;
+        public final AccessibilityNodeInfo.AccessibilityAction accessibilityAction;
+
+        private final BaseAccessibilityDelegate<T> mDelegate;
+
+        public LauncherAction(int id, int labelRes, int keyCode) {
+            this.keyCode = keyCode;
+            accessibilityAction = new AccessibilityNodeInfo.AccessibilityAction(
+                    id, mContext.getString(labelRes));
+            mDelegate = BaseAccessibilityDelegate.this;
+        }
+
+        /**
+         * Invokes the action for the provided host
+         */
+        public boolean invokeFromKeyboard(View host) {
+            if (host != null && host.getTag() instanceof ItemInfo) {
+                return mDelegate.performAction(
+                        host, (ItemInfo) host.getTag(), accessibilityAction.getId(), true);
+            } else {
+                return false;
+            }
+        }
+    }
+}