1/* 2 * Copyright 2018 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 androidx.recyclerview.widget; 18 19import android.graphics.Canvas; 20import android.view.View; 21 22/** 23 * Utility class for {@link ItemTouchHelper} which handles item transformations for different 24 * API versions. 25 * <p/> 26 * This class has methods that map to {@link ItemTouchHelper.Callback}'s drawing methods. Default 27 * implementations in {@link ItemTouchHelper.Callback} call these methods with 28 * {@link RecyclerView.ViewHolder#itemView} and {@link ItemTouchUIUtil} makes necessary changes 29 * on the View depending on the API level. You can access the instance of {@link ItemTouchUIUtil} 30 * via {@link ItemTouchHelper.Callback#getDefaultUIUtil()} and call its methods with the children 31 * of ViewHolder that you want to apply default effects. 32 * 33 * @see ItemTouchHelper.Callback#getDefaultUIUtil() 34 */ 35public interface ItemTouchUIUtil { 36 37 /** 38 * The default implementation for {@link ItemTouchHelper.Callback#onChildDraw(Canvas, 39 * RecyclerView, RecyclerView.ViewHolder, float, float, int, boolean)} 40 */ 41 void onDraw(Canvas c, RecyclerView recyclerView, View view, 42 float dX, float dY, int actionState, boolean isCurrentlyActive); 43 44 /** 45 * The default implementation for {@link ItemTouchHelper.Callback#onChildDrawOver(Canvas, 46 * RecyclerView, RecyclerView.ViewHolder, float, float, int, boolean)} 47 */ 48 void onDrawOver(Canvas c, RecyclerView recyclerView, View view, 49 float dX, float dY, int actionState, boolean isCurrentlyActive); 50 51 /** 52 * The default implementation for {@link ItemTouchHelper.Callback#clearView(RecyclerView, 53 * RecyclerView.ViewHolder)} 54 */ 55 void clearView(View view); 56 57 /** 58 * The default implementation for {@link ItemTouchHelper.Callback#onSelectedChanged( 59 * RecyclerView.ViewHolder, int)} 60 */ 61 void onSelected(View view); 62} 63 64