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

   1 /*
   2  * Copyright(c) 2021 Samsung Electronics Co., Ltd.
   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 using System;
  18 using System.Collections.Generic;
  19 using System.ComponentModel;
  20 using Tizen.NUI.BaseComponents;
  21
  22 namespace Tizen.NUI.Components
  23 {
  24     /// <summary>
  25     /// TabButtonSelectedEventArgs is a class to record tab button selected event
  26     /// arguments which will be sent to a user.
  27     /// </summary>
  28     [EditorBrowsable(EditorBrowsableState.Never)]
  29     public class TabButtonSelectedEventArgs : EventArgs
  30     {
  31         /// <summary>
  32         /// Creates a new instance of TabButtonSelectedEventArgs.
  33         /// </summary>
  34         /// <param name="index">The selected index.</param>
  35         [EditorBrowsable(EditorBrowsableState.Never)]
  36         public TabButtonSelectedEventArgs(int index)
  37         {
  38             Index = index;
  39         }
  40
  41         /// <summary>
  42         /// The index of the selected tab button.
  43         /// </summary>
  44         [EditorBrowsable(EditorBrowsableState.Never)]
  45         public int Index { get; }
  46     }
  47
  48     /// <summary>
  49     /// TabBar is a class which contains a set of TabButtons and has one of them selected.
  50     /// </summary>
  51     [EditorBrowsable(EditorBrowsableState.Never)]
  52     public class TabBar : Control
  53     {
  54         private IList<TabButton> tabButtons;
  55
  56         private TabButtonGroup tabButtonGroup;
  57
  58         /// <summary>
  59         /// Creates a new instance of TabBar.
  60         /// </summary>
  61         [EditorBrowsable(EditorBrowsableState.Never)]
  62         public TabBar()
  63         {
  64             Layout = new LinearLayout() { LinearOrientation = LinearLayout.Orientation.Horizontal };
  65
  66             WidthSpecification = LayoutParamPolicies.MatchParent;
  67
  68             tabButtons = new List<TabButton>();
  69             tabButtonGroup = new TabButtonGroup();
  70             SelectedIndex = -1;
  71         }
  72
  73         /// <summary>
  74         /// An event for the tab button selected signal which can be used to
  75         /// subscribe or unsubscribe the event handler provided by a user.
  76         /// </summary>
  77         [EditorBrowsable(EditorBrowsableState.Never)]
  78         public event EventHandler<TabButtonSelectedEventArgs> TabButtonSelected;
  79
  80         /// <summary>
  81         /// The index of the selected tab button.
  82         /// </summary>
  83         [EditorBrowsable(EditorBrowsableState.Never)]
  84         protected int SelectedIndex { get; set; }
  85
  86         /// <summary>
  87         /// Gets the count of tab buttons.
  88         /// </summary>
  89         [EditorBrowsable(EditorBrowsableState.Never)]
  90         public int TabButtonCount => tabButtons.Count;
  91
  92         /// <summary>
  93         /// Adds a tab button to TabBar.
  94         /// </summary>
  95         /// <param name="tabButton">A tab button to be added to TabBar.</param>
  96         /// <exception cref="ArgumentNullException">Thrown when the argument tabButton is null.</exception>
  97         [EditorBrowsable(EditorBrowsableState.Never)]
  98         protected internal void AddTabButton(TabButton tabButton)
  99         {
 100             if (tabButton == null)
 101             {
 102                 throw new ArgumentNullException(nameof(tabButton), "tabButton should not be null.");
 103             }
 104
 105             tabButtons.Add(tabButton);
 106             Add(tabButton);
 107             tabButtonGroup.Add(tabButton);
 108
 109             tabButton.Clicked += (object sender, ClickedEventArgs e) =>
 110             {
 111                 int index = tabButtons.IndexOf(tabButton);
 112
 113                 if (SelectedIndex == index)
 114                 {
 115                     return;
 116                 }
 117
 118                 SelectedIndex = index;
 119
 120                 if (TabButtonSelected != null)
 121                 {
 122                     TabButtonSelectedEventArgs args = new TabButtonSelectedEventArgs(SelectedIndex);
 123                     TabButtonSelected(this, args);
 124                 }
 125             };
 126
 127             if (SelectedIndex == -1)
 128             {
 129                 tabButton.IsSelected = true;
 130                 SelectedIndex = 0;
 131
 132                 if (TabButtonSelected != null)
 133                 {
 134                     TabButtonSelectedEventArgs args = new TabButtonSelectedEventArgs(SelectedIndex);
 135                     TabButtonSelected(this, args);
 136                 }
 137             }
 138
 139             //TODO: To support non-unified tab button size.
 140             CalculateUnifiedTabButtonSize();
 141         }
 142
 143         /// <summary>
 144         /// Removes a tab button from TabBar.
 145         /// </summary>
 146         /// <param name="tabButton">A tab button to be removed from TabBar.</param>
 147         /// <exception cref="ArgumentNullException">Thrown when the argument tabButton is null.</exception>
 148         /// <exception cref="ArgumentException">Thrown when the argument tabButton does not exist in TabBar.</exception>
 149         [EditorBrowsable(EditorBrowsableState.Never)]
 150         protected internal void RemoveTabButton(TabButton tabButton)
 151         {
 152             if (tabButton == null)
 153             {
 154                 throw new ArgumentNullException(nameof(tabButton), "tabButton should not be null.");
 155             }
 156
 157             if (tabButtons.Contains(tabButton) == false)
 158             {
 159                 throw new ArgumentException("tabButton does not exist in TabBar.", nameof(tabButton));
 160             }
 161
 162             int index = tabButtons.IndexOf(tabButton);
 163             TabButton selectedTabButton = tabButtons[SelectedIndex];
 164
 165             tabButtons.Remove(tabButton);
 166             Remove(tabButton);
 167             tabButtonGroup.Remove(tabButton);
 168
 169             if ((index < SelectedIndex) || (tabButtons.Count == SelectedIndex))
 170             {
 171                 SelectedIndex -= 1;
 172
 173                 if (TabButtonSelected != null)
 174                 {
 175                     TabButtonSelectedEventArgs args = new TabButtonSelectedEventArgs(SelectedIndex);
 176                     TabButtonSelected(this, args);
 177                 }
 178             }
 179
 180             if ((SelectedIndex != -1) && (selectedTabButton != tabButtons[SelectedIndex]))
 181             {
 182                 tabButtons[SelectedIndex].IsSelected = true;
 183             }
 184
 185             //TODO: To support non-unified tab button size.
 186             CalculateUnifiedTabButtonSize();
 187         }
 188
 189         /// <inheritdoc/>
 190         public override void OnRelayout(Vector2 size, RelayoutContainer container)
 191         {
 192             base.OnRelayout(size, container);
 193
 194             //TODO: To support non-unified tab button size.
 195             CalculateUnifiedTabButtonSize();
 196         }
 197
 198         private void CalculateUnifiedTabButtonSize()
 199         {
 200             if (tabButtons.Count <= 0)
 201             {
 202                 return;
 203             }
 204
 205             var tabButtonWidth = Size.Width / tabButtons.Count;
 206
 207             foreach (TabButton tabButton in tabButtons)
 208             {
 209                 if (tabButton.Size.Width != tabButtonWidth)
 210                 {
 211                     tabButton.Size = new Size(tabButtonWidth, tabButton.Size.Height);
 212                 }
 213             }
 214         }
 215
 216         /// <summary>
 217         /// Gets the tab button at the specified index of TabBar.
 218         /// </summary>
 219         /// <param name="index">The index of TabBar where the specified tab button exists.</param>
 220         /// <exception cref="ArgumentOutOfRangeException">Thrown when the index is less than 0, or greater than or equal to the number of tab buttons.</exception>
 221         [EditorBrowsable(EditorBrowsableState.Never)]
 222         public TabButton GetTabButton(int index)
 223         {
 224             if ((index < 0) || (index >= tabButtons.Count))
 225             {
 226                 throw new ArgumentOutOfRangeException(nameof(index), "index should not be greater than or equal to 0, and less than the number of tab buttons.");
 227             }
 228
 229             return tabButtons[index];
 230         }
 231
 232         /// <summary>
 233         /// Dispose TabBar and all children on it.
 234         /// </summary>
 235         /// <param name="type">Dispose type.</param>
 236         [EditorBrowsable(EditorBrowsableState.Never)]
 237         protected override void Dispose(DisposeTypes type)
 238         {
 239             if (disposed)
 240             {
 241                 return;
 242             }
 243
 244             if (type == DisposeTypes.Explicit)
 245             {
 246                 if (tabButtons != null)
 247                 {
 248                     foreach (TabButton tabButton in tabButtons)
 249                     {
 250                         Utility.Dispose(tabButton);
 251                     }
 252
 253                     tabButtons = null;
 254                 }
 255
 256                 tabButtonGroup = null;
 257             }
 258
 259             base.Dispose(type);
 260         }
 261     }
 262 }