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 17 package com.android.launcher3.dragndrop; 18 19 import android.graphics.Point; 20 21 import com.android.launcher3.DropTarget; 22 23 /** 24 * Set of options to control the drag and drop behavior. 25 */ 26 public 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 /** Scale of the icons over the workspace icon size. */ 38 public float intrinsicIconScaleFactor = 1f; 39 40 /** 41 * Specifies a condition that must be met before DragListener#onDragStart() is called. 42 * By default, there is no condition and onDragStart() is called immediately following 43 * DragController#startDrag(). 44 * 45 * This condition can be overridden, and callbacks are provided for the following cases: 46 * - The pre-drag starts, but onDragStart() is deferred (onPreDragStart()). 47 * - The pre-drag ends before the condition is met (onPreDragEnd(false)). 48 * - The actual drag starts when the condition is met (onPreDragEnd(true)). 49 */ 50 public interface PreDragCondition { 51 shouldStartDrag(double distanceDragged)52 public boolean shouldStartDrag(double distanceDragged); 53 54 /** 55 * The pre-drag has started, but onDragStart() is 56 * deferred until shouldStartDrag() returns true. 57 */ onPreDragStart(DropTarget.DragObject dragObject)58 void onPreDragStart(DropTarget.DragObject dragObject); 59 60 /** 61 * The pre-drag has ended. This gets called at the same time as onDragStart() 62 * if the condition is met, otherwise at the same time as onDragEnd(). 63 * @param dragStarted Whether the pre-drag ended because the actual drag started. 64 * This will be true if the condition was met, otherwise false. 65 */ onPreDragEnd(DropTarget.DragObject dragObject, boolean dragStarted)66 void onPreDragEnd(DropTarget.DragObject dragObject, boolean dragStarted); 67 } 68 } 69