1/*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.launcher3.dragndrop;
18
19import android.graphics.Point;
20
21import com.android.launcher3.DropTarget;
22
23/**
24 * Set of options to control the drag and drop behavior.
25 */
26public class DragOptions {
27
28    /** Whether or not an accessible drag operation is in progress. */
29    public boolean isAccessibleDrag = false;
30
31    /** Specifies the start location for the system DnD, null when using internal DnD */
32    public Point systemDndStartPoint = null;
33
34    /** Determines when a pre-drag should transition to a drag. By default, this is immediate. */
35    public PreDragCondition preDragCondition = null;
36
37    /**
38     * Specifies a condition that must be met before DragListener#onDragStart() is called.
39     * By default, there is no condition and onDragStart() is called immediately following
40     * DragController#startDrag().
41     *
42     * This condition can be overridden, and callbacks are provided for the following cases:
43     * - The pre-drag starts, but onDragStart() is deferred (onPreDragStart()).
44     * - The pre-drag ends before the condition is met (onPreDragEnd(false)).
45     * - The actual drag starts when the condition is met (onPreDragEnd(true)).
46     */
47    public interface PreDragCondition {
48
49        public boolean shouldStartDrag(double distanceDragged);
50
51        /**
52         * The pre-drag has started, but onDragStart() is
53         * deferred until shouldStartDrag() returns true.
54         */
55        void onPreDragStart(DropTarget.DragObject dragObject);
56
57        /**
58         * The pre-drag has ended. This gets called at the same time as onDragStart()
59         * if the condition is met, otherwise at the same time as onDragEnd().
60         * @param dragStarted Whether the pre-drag ended because the actual drag started.
61         *                    This will be true if the condition was met, otherwise false.
62         */
63        void onPreDragEnd(DropTarget.DragObject dragObject, boolean dragStarted);
64    }
65}
66