SimpleTraversalStrategy.java

/*
 * Copyright (C) 2015 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.utils.traversal;

import android.support.v4.view.accessibility.AccessibilityNodeInfoCompat;
import com.android.utils.AccessibilityNodeInfoRef;

import java.util.Map;

public class SimpleTraversalStrategy implements TraversalStrategy {

    @Override
    public AccessibilityNodeInfoCompat findFocus(AccessibilityNodeInfoCompat startNode,
                                                 @SearchDirection int direction) {
        if (startNode == null) {
            return null;
        }

        AccessibilityNodeInfoRef ref = AccessibilityNodeInfoRef.obtain(startNode);
        boolean focusFound = direction == TraversalStrategy.SEARCH_FOCUS_FORWARD ?
                ref.nextInOrder() : ref.previousInOrder();
        if (focusFound) {
            return ref.get();
        }

        ref.recycle();
        return null;
    }

    @Override
    public AccessibilityNodeInfoCompat focusInitial(AccessibilityNodeInfoCompat root,
            @SearchDirection int direction) {
        if (root == null) {
            return null;
        }

        if (direction == SEARCH_FOCUS_FORWARD) {
            return AccessibilityNodeInfoCompat.obtain(root);
        } else if (direction == SEARCH_FOCUS_BACKWARD) {
            AccessibilityNodeInfoRef ref = AccessibilityNodeInfoRef.obtain(root);
            if (ref.lastDescendant()) {
                return ref.get();
            } else {
                ref.recycle();
                return null;
            }
        }

        return null;
    }

    @Override
    public Map<AccessibilityNodeInfoCompat, Boolean> getSpeakingNodesCache() {
        return null;
    }

    @Override
    public void recycle() {
    }
}