src/Tizen.NUI.Components/Controls/RecyclerView/RecyclerView.cs

   1 /* Copyright (c) 2020 Samsung Electronics Co., Ltd.
   2  *
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at
   6  *
   7  * http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  *
  15  */
  16 using System;
  17 using Tizen.NUI.BaseComponents;
  18 using System.Collections.Generic;
  19 using System.ComponentModel;
  20
  21 namespace Tizen.NUI.Components
  22 {
  23     /// <summary>
  24     /// [Draft] This class provides a View that can recycle items to improve performance.
  25     /// </summary>
  26     /// This may be public opened in tizen_6.0 after ACR done. Before ACR, need to be hidden as inhouse API.
  27     [EditorBrowsable(EditorBrowsableState.Never)]
  28     public class RecyclerView : ScrollableBase
  29     {
  30         protected RecycleAdapter mAdapter;
  31         protected View mContainer;
  32         protected RecycleLayoutManager mLayoutManager;
  33         protected int mTotalItemCount = 15;
  34         private List<PropertyNotification> notifications = new List<PropertyNotification>();
  35
  36         public RecyclerView() : base()
  37         {
  38             Initialize(new RecycleAdapter(), new RecycleLayoutManager());
  39         }
  40
  41         /// <summary>
  42         /// Default constructor.
  43         /// </summary>
  44         /// <param name="adapter">Recycle adapter of RecyclerView.</param>
  45         /// <param name="layoutManager">Recycle layoutManager of RecyclerView.</param>
  46         /// <since_tizen> 8 </since_tizen>
  47         /// This may be public opened in tizen_6.0 after ACR done. Before ACR, need to be hidden as inhouse API
  48         [EditorBrowsable(EditorBrowsableState.Never)]
  49         public RecyclerView(RecycleAdapter adapter, RecycleLayoutManager layoutManager)
  50         {
  51             Initialize(adapter, layoutManager);
  52         }
  53
  54         private void Initialize(RecycleAdapter adapter, RecycleLayoutManager layoutManager)
  55         {
  56             Scrolling += OnScrolling;
  57
  58             mAdapter = adapter;
  59             mAdapter.OnDataChanged += OnAdapterDataChanged;
  60
  61             mLayoutManager = layoutManager;
  62             mLayoutManager.Container = ContentContainer;
  63             mLayoutManager.ItemSize = mAdapter.CreateRecycleItem().Size;
  64             mLayoutManager.DataCount = mAdapter.Data.Count;
  65
  66             InitializeItems();
  67         }
  68
  69         private void OnItemSizeChanged(object source, PropertyNotification.NotifyEventArgs args)
  70         {
  71             mLayoutManager.Layout(ScrollingDirection == Direction.Horizontal ? ContentContainer.CurrentPosition.X : ContentContainer.CurrentPosition.Y);
  72         }
  73
  74         public int TotalItemCount
  75         {
  76             get
  77             {
  78                 return mTotalItemCount;
  79             }
  80             set
  81             {
  82                 mTotalItemCount = value;
  83                 InitializeItems();
  84             }
  85         }
  86
  87         private void InitializeItems()
  88         {
  89             for(int i = Children.Count -1 ; i > -1 ; i--)
  90             {
  91                 Children[i].Unparent();
  92                 notifications[i].Notified -= OnItemSizeChanged;
  93                 notifications.RemoveAt(i);
  94             }
  95
  96             for (int i = 0; i < mTotalItemCount; i++)
  97             {
  98                 RecycleItem item = mAdapter.CreateRecycleItem();
  99                 item.DataIndex = i;
 100                 item.Name = "[" + i + "] recycle";
 101
 102                 if (i < mAdapter.Data.Count)
 103                 {
 104                     mAdapter.BindData(item);
 105                 }
 106                 Add(item);
 107
 108                 PropertyNotification noti = item.AddPropertyNotification("size", PropertyCondition.Step(0.1f));
 109                 noti.Notified += OnItemSizeChanged;
 110                 notifications.Add(noti);
 111             }
 112
 113             mLayoutManager.Layout(0.0f);
 114
 115             if (ScrollingDirection == Direction.Horizontal)
 116             {
 117                 ContentContainer.SizeWidth = mLayoutManager.CalculateLayoutOrientationSize();
 118             }
 119             else
 120             {
 121                 ContentContainer.SizeHeight = mLayoutManager.CalculateLayoutOrientationSize();
 122             }
 123         }
 124
 125
 126         public new Direction ScrollingDirection
 127         {
 128             get
 129             {
 130                 return base.ScrollingDirection;
 131             }
 132             set
 133             {
 134                 base.ScrollingDirection = value;
 135
 136                 if (ScrollingDirection == Direction.Horizontal)
 137                 {
 138                     ContentContainer.SizeWidth = mLayoutManager.CalculateLayoutOrientationSize();
 139                 }
 140                 else
 141                 {
 142                     ContentContainer.SizeHeight = mLayoutManager.CalculateLayoutOrientationSize();
 143                 }
 144             }
 145         }
 146
 147         /// <summary>
 148         /// Recycler adpater.
 149         /// </summary>
 150         /// <since_tizen> 8 </since_tizen>
 151         /// This may be public opened in tizen_6.0 after ACR done. Before ACR, need to be hidden as inhouse API
 152         [EditorBrowsable(EditorBrowsableState.Never)]
 153         public RecycleAdapter Adapter
 154         {
 155             get
 156             {
 157                 return mAdapter;
 158             }
 159             set
 160             {
 161                 if(mAdapter != null)
 162                 {
 163                     mAdapter.OnDataChanged -= OnAdapterDataChanged;
 164                 }
 165
 166                 mAdapter = value;
 167                 mAdapter.OnDataChanged += OnAdapterDataChanged;
 168                 mLayoutManager.ItemSize = mAdapter.CreateRecycleItem().Size;
 169                 mLayoutManager.DataCount = mAdapter.Data.Count;
 170                 InitializeItems();
 171             }
 172         }
 173
 174         /// <summary>
 175         /// Recycler layoutManager.
 176         /// </summary>
 177         /// <since_tizen> 8 </since_tizen>
 178         /// This may be public opened in tizen_6.0 after ACR done. Before ACR, need to be hidden as inhouse API
 179         [EditorBrowsable(EditorBrowsableState.Never)]
 180         public RecycleLayoutManager LayoutManager
 181         {
 182             get
 183             {
 184                 return mLayoutManager;
 185             }
 186             set
 187             {
 188                 mLayoutManager = value;
 189                 mLayoutManager.Container = ContentContainer;
 190                 mLayoutManager.ItemSize = mAdapter.CreateRecycleItem().Size;
 191                 mLayoutManager.DataCount = mAdapter.Data.Count;
 192                 InitializeItems();
 193             }
 194         }
 195
 196         private void OnScrolling(object source, ScrollEventArgs args)
 197         {
 198             mLayoutManager.Layout(ScrollingDirection == Direction.Horizontal ? args.Position.X : args.Position.Y);
 199             List<RecycleItem> recycledItemList = mLayoutManager.Recycle(ScrollingDirection == Direction.Horizontal ? args.Position.X : args.Position.Y);
 200             BindData(recycledItemList);
 201         }
 202
 203         private void OnAdapterDataChanged(object source, EventArgs args)
 204         {
 205             List<RecycleItem> changedData = new List<RecycleItem>();
 206
 207             foreach (RecycleItem item in Children)
 208             {
 209                 changedData.Add(item);
 210             }
 211
 212             BindData(changedData);
 213         }
 214
 215         private void BindData(List<RecycleItem> changedData)
 216         {
 217             foreach (RecycleItem item in changedData)
 218             {
 219                 if (item.DataIndex > -1 && item.DataIndex < mAdapter.Data.Count)
 220                 {
 221                     item.Show();
 222                     item.Name = "["+item.DataIndex+"]";
 223                     mAdapter.BindData(item);
 224                 }
 225                 else
 226                 {
 227                     item.Hide();
 228                 }
 229             }
 230         }
 231
 232         /// <summary>
 233         /// Adjust scrolling position by own scrolling rules.
 234         /// Override this function when developer wants to change destination of flicking.(e.g. always snap to center of item)
 235         /// </summary>
 236         /// <param name="position">Scroll position which is calculated by ScrollableBase</param>
 237         /// <returns>Adjusted scroll destination</returns>
 238         /// <since_tizen> 8 </since_tizen>
 239         /// This may be public opened in tizen_6.0 after ACR done. Before ACR, need to be hidden as inhouse API
 240         [EditorBrowsable(EditorBrowsableState.Never)]
 241         protected override float AdjustTargetPositionOfScrollAnimation(float position)
 242         {
 243             // Destination is depending on implementation of layout manager.
 244             // Get destination from layout manager.
 245             return mLayoutManager.CalculateCandidateScrollPosition(position);
 246         }
 247     }
 248 }