| | 1 | | using PropertyGridHelpers.Support; |
| | 2 | | using PropertyGridHelpers.UIEditors; |
| | 3 | | using System; |
| | 4 | | using System.ComponentModel; |
| | 5 | | using System.Globalization; |
| | 6 | | using System.Windows.Forms; |
| | 7 | | using System.Drawing.Design; |
| | 8 | |
|
| | 9 | | namespace PropertyGridHelpers.Controls |
| | 10 | | { |
| | 11 | | /// <summary> |
| | 12 | | /// A custom <see cref="CheckedListBox"/> control designed for editing |
| | 13 | | /// properties backed by [Flags] enumerations. It presents each enum value |
| | 14 | | /// as a checkbox, allowing users to select multiple values that combine |
| | 15 | | /// into a composite flag. |
| | 16 | | /// |
| | 17 | | /// This control is typically hosted in a drop-down editor (e.g., |
| | 18 | | /// <see cref="UITypeEditor"/>) using <see cref="DropDownVisualizer{TControl}"/> |
| | 19 | | /// to support property editing within a <see cref="PropertyGrid"/>. |
| | 20 | | /// </summary> |
| | 21 | | /// <remarks> |
| | 22 | | /// When the associated enum is set via the <see cref="EnumValue"/> property, |
| | 23 | | /// the control automatically populates with all defined enum values and |
| | 24 | | /// checks those corresponding to the current composite value. |
| | 25 | | /// As checkboxes are toggled, the internal representation is updated accordingly. |
| | 26 | | /// |
| | 27 | | /// This control assumes that the enum is decorated with the |
| | 28 | | /// <see cref="FlagsAttribute"/>; an exception will be thrown otherwise. |
| | 29 | | /// |
| | 30 | | /// Optional display customization is supported via a custom |
| | 31 | | /// <see cref="EnumConverter"/> assigned to |
| | 32 | | /// <see cref="Converter"/>. |
| | 33 | | /// </remarks> |
| | 34 | | /// <example> |
| | 35 | | /// Typical usage: |
| | 36 | | /// <code> |
| | 37 | | /// [Editor(typeof(FlagEnumUIEditor), typeof(UITypeEditor))] |
| | 38 | | /// public MyFlagsEnum FlagsProperty { get; set; } |
| | 39 | | /// </code> |
| | 40 | | /// </example> |
| | 41 | | /// <seealso cref="CheckedListBox"/> |
| | 42 | | /// <seealso cref="IDropDownEditorControl"/> |
| | 43 | | /// <seealso cref="DropDownVisualizer{TControl}"/> |
| | 44 | | /// <seealso cref="FlagEnumUIEditor"/> |
| | 45 | | /// <seealso cref="FlagEnumUIEditor{T}"/> |
| | 46 | | public partial class FlagCheckedListBox |
| | 47 | | : CheckedListBox, IDropDownEditorControl |
| | 48 | | { |
| | 49 | | /// <summary> |
| | 50 | | /// Initializes a new instance of the <see cref="FlagCheckedListBox" /> class. |
| | 51 | | /// </summary> |
| 128 | 52 | | public FlagCheckedListBox() => |
| 128 | 53 | | InitializeComponent(); |
| | 54 | |
|
| | 55 | | /// <summary> |
| | 56 | | /// Occurs when the user has finished editing the selection |
| | 57 | | /// and commits the current value. |
| | 58 | | /// </summary> |
| 128 | 59 | | public event EventHandler ValueCommitted = delegate { }; |
| | 60 | |
|
| | 61 | | /// <summary> |
| | 62 | | /// Releases unmanaged and - optionally - managed resources. |
| | 63 | | /// </summary> |
| | 64 | | /// <param name="disposing"><c>true</c> to release both managed and unmanaged resources; <c>false</c> to release |
| 128 | 65 | | protected override void Dispose(bool disposing) => base.Dispose(disposing); |
| | 66 | |
|
| | 67 | | #region Component Designer generated code ^^^^^^^^^ |
| | 68 | |
|
| | 69 | | /// <summary> |
| | 70 | | /// Initializes the component. |
| | 71 | | /// </summary> |
| | 72 | | private void InitializeComponent() => |
| 128 | 73 | | CheckOnClick = true; |
| | 74 | |
|
| | 75 | | #endregion |
| | 76 | |
|
| | 77 | | /// <summary> |
| | 78 | | /// Adds a new item to the checklist with the specified bitwise value and display caption. |
| | 79 | | /// </summary> |
| | 80 | | /// <param name="value">The bitwise integer value representing a flag.</param> |
| | 81 | | /// <param name="caption">The display text for the item.</param> |
| | 82 | | /// <returns> |
| | 83 | | /// A <see cref="FlagCheckedListBoxItem"/> representing the added item. |
| | 84 | | /// </returns> |
| | 85 | | public FlagCheckedListBoxItem Add(int value, string caption) |
| 188 | 86 | | { |
| 196 | 87 | | var item = new FlagCheckedListBoxItem(value, caption); |
| 196 | 88 | | _ = Items.Add(item); |
| 196 | 89 | | return item; |
| 188 | 90 | | } |
| | 91 | |
|
| | 92 | | /// <summary> |
| | 93 | | /// Removes all items from the checklist and resets its state. |
| | 94 | | /// </summary> |
| | 95 | | public void Clear() => |
| 20 | 96 | | Items.Clear(); |
| | 97 | |
|
| | 98 | | /// <summary> |
| | 99 | | /// Adds an existing <see cref="FlagCheckedListBoxItem"/> to the checklist. |
| | 100 | | /// </summary> |
| | 101 | | /// <param name="item">The item to add.</param> |
| | 102 | | /// <returns> |
| | 103 | | /// The added <see cref="FlagCheckedListBoxItem"/>. |
| | 104 | | /// </returns> |
| | 105 | | public FlagCheckedListBoxItem Add(FlagCheckedListBoxItem item) |
| 44 | 106 | | { |
| 52 | 107 | | _ = Items.Add(item); |
| 48 | 108 | | return item; |
| 40 | 109 | | } |
| | 110 | |
|
| | 111 | | /// <summary> |
| | 112 | | /// Raises the <see cref="CheckedListBox.ItemCheck" /> event. |
| | 113 | | /// </summary> |
| | 114 | | /// <param name="ice">The <see cref="ItemCheckEventArgs" /> instance containing the event data.</param> |
| | 115 | | protected override void OnItemCheck(ItemCheckEventArgs ice) |
| 104 | 116 | | { |
| 112 | 117 | | base.OnItemCheck(ice); |
| | 118 | |
|
| 112 | 119 | | if (ice == null) return; |
| | 120 | |
|
| 112 | 121 | | if (isUpdatingCheckStates) |
| 92 | 122 | | return; |
| | 123 | |
|
| | 124 | | // Get the checked/unchecked item |
| 36 | 125 | | var item = Items[ice.Index] as FlagCheckedListBoxItem; |
| | 126 | | // Update other items |
| 36 | 127 | | UpdateCheckedItems(item, ice.NewValue); |
| 112 | 128 | | } |
| | 129 | |
|
| | 130 | | /// <summary> |
| | 131 | | /// Updates the check state of all items based on the provided bitwise value. |
| | 132 | | /// </summary> |
| | 133 | | /// <param name="value"> |
| | 134 | | /// A bitwise integer representing the currently active flags. |
| | 135 | | /// </param> |
| | 136 | | protected internal void UpdateCheckedItems(int value) |
| 84 | 137 | | { |
| 92 | 138 | | isUpdatingCheckStates = true; |
| | 139 | |
|
| | 140 | | // Iterate over all items |
| 584 | 141 | | for (var i = 0; i < Items.Count; i++) |
| 216 | 142 | | { |
| 224 | 143 | | var item = Items[i] as FlagCheckedListBoxItem; |
| | 144 | |
|
| 224 | 145 | | switch (item.Value) |
| | 146 | | { |
| | 147 | | case 0: |
| 48 | 148 | | SetItemChecked(i, value == 0); |
| 48 | 149 | | break; |
| | 150 | | default: |
| | 151 | | // If the bit for the current item is on in the bit value, check it |
| 192 | 152 | | SetItemChecked(i, (item.Value & value) == item.Value && item.Value != 0); |
| 184 | 153 | | break; |
| | 154 | | } |
| 216 | 155 | | } |
| | 156 | |
|
| 92 | 157 | | isUpdatingCheckStates = false; |
| 92 | 158 | | } |
| | 159 | |
|
| | 160 | | /// <summary> |
| | 161 | | /// Updates the check states of items in response to a change in one item, |
| | 162 | | /// maintaining the consistency of the composite flag value. |
| | 163 | | /// </summary> |
| | 164 | | /// <param name="composite">The item that changed.</param> |
| | 165 | | /// <param name="cs">The new check state of that item.</param> |
| | 166 | | protected internal void UpdateCheckedItems( |
| | 167 | | FlagCheckedListBoxItem composite, |
| | 168 | | CheckState cs) |
| 44 | 169 | | { |
| | 170 | | // If the value of the item is 0, call directly. |
| 52 | 171 | | if (composite?.Value == 0) |
| 20 | 172 | | UpdateCheckedItems(0); |
| | 173 | |
|
| | 174 | | // Get the total value of all checked items |
| 52 | 175 | | var sum = 0; |
| 200 | 176 | | for (var i = 0; i < Items.Count; i++) |
| 64 | 177 | | { |
| 72 | 178 | | var item = Items[i] as FlagCheckedListBoxItem; |
| | 179 | |
|
| | 180 | | // If item is checked, add its value to the sum. |
| 72 | 181 | | if (GetItemChecked(i)) |
| 36 | 182 | | sum |= item.Value; |
| 64 | 183 | | } |
| | 184 | |
|
| | 185 | | // Check if composite is null before accessing its Value |
| 52 | 186 | | if (composite != null) |
| 40 | 187 | | { |
| | 188 | | // If the item has been unchecked, remove its bits from the sum |
| 48 | 189 | | if (cs == CheckState.Unchecked) |
| 20 | 190 | | sum &= ~composite.Value; |
| | 191 | | // If the item has been checked, combine its bits with the sum |
| | 192 | | else |
| 44 | 193 | | sum |= composite.Value; |
| 40 | 194 | | } |
| | 195 | |
|
| | 196 | | // Update all items in the CheckListBox based on the final bit value |
| 52 | 197 | | UpdateCheckedItems(sum); |
| 52 | 198 | | } |
| | 199 | |
|
| | 200 | | private bool isUpdatingCheckStates; |
| | 201 | |
|
| | 202 | | /// <summary> |
| | 203 | | /// Gets the composite integer value representing all currently checked flags. |
| | 204 | | /// </summary> |
| | 205 | | /// <returns> |
| | 206 | | /// An <see cref="int"/> value encoding the combined flags of checked items. |
| | 207 | | /// </returns> |
| | 208 | | public int GetCurrentValue() |
| 64 | 209 | | { |
| 72 | 210 | | var sum = 0; |
| | 211 | |
|
| 480 | 212 | | for (var i = 0; i < Items.Count; i++) |
| 184 | 213 | | { |
| 192 | 214 | | var item = Items[i] as FlagCheckedListBoxItem; |
| | 215 | |
|
| 192 | 216 | | if (GetItemChecked(i)) |
| 80 | 217 | | sum |= item.Value; |
| 184 | 218 | | } |
| | 219 | |
|
| 72 | 220 | | return sum; |
| 64 | 221 | | } |
| | 222 | |
|
| | 223 | | /// <summary> |
| | 224 | | /// The type of the enum currently bound to this control. |
| | 225 | | /// </summary> |
| | 226 | | private Type enumType; |
| | 227 | | /// <summary> |
| | 228 | | /// The current enum value represented by the checked items. |
| | 229 | | /// </summary> |
| | 230 | | private Enum enumValue; |
| | 231 | |
|
| | 232 | | /// <summary> |
| | 233 | | /// Populates the checklist with entries corresponding to each member of the bound enum type. |
| | 234 | | /// </summary> |
| | 235 | | private void FillEnumMembers() |
| 44 | 236 | | { |
| 420 | 237 | | foreach (var name in Enum.GetNames(enumType)) |
| 156 | 238 | | { |
| 164 | 239 | | var val = Enum.Parse(enumType, name); |
| 164 | 240 | | var caption = Converter == null ? name : (string)Converter.ConvertTo(Context, Culture, val, typeof(strin |
| 164 | 241 | | var intVal = (int)Convert.ChangeType(val, typeof(int), CultureInfo.CurrentCulture); |
| | 242 | |
|
| 164 | 243 | | _ = Add(intVal, caption); |
| 156 | 244 | | } |
| 52 | 245 | | } |
| | 246 | |
|
| | 247 | | /// <summary> |
| | 248 | | /// Synchronizes the check state of items in the list to reflect the current <see cref="EnumValue"/>. |
| | 249 | | /// </summary> |
| | 250 | | /// <remarks> |
| | 251 | | /// This ensures the visual checklist matches the current bitwise value. |
| | 252 | | /// </remarks> |
| | 253 | | private void ApplyEnumValue() |
| 44 | 254 | | { |
| 52 | 255 | | var intVal = (int)Convert.ChangeType(enumValue, typeof(int), CultureInfo.CurrentCulture); |
| 52 | 256 | | UpdateCheckedItems(intVal); |
| 52 | 257 | | } |
| | 258 | |
|
| | 259 | | /// <summary> |
| | 260 | | /// Gets or sets the current enum value represented by the checked items |
| | 261 | | /// in the list. This property serves as the main interface for binding |
| | 262 | | /// a flags-based enum to the control. |
| | 263 | | /// </summary> |
| | 264 | | /// <remarks> |
| | 265 | | /// <para> |
| | 266 | | /// When setting this property, the control performs the following: |
| | 267 | | /// </para> |
| | 268 | | /// <list type="bullet"> |
| | 269 | | /// <item><description>Verifies the provided value is a valid enum marked with the <see cref="FlagsAttribute"/ |
| | 270 | | /// <item><description>Clears any existing items in the list.</description></item> |
| | 271 | | /// <item><description>Populates the list with all members of the enum type.</description></item> |
| | 272 | | /// <item><description>Automatically checks the items corresponding to the current flags set in the value.</de |
| | 273 | | /// </list> |
| | 274 | | /// <para> |
| | 275 | | /// When getting this property, it returns the composite enum value |
| | 276 | | /// corresponding to the checked items. |
| | 277 | | /// </para> |
| | 278 | | /// <para> |
| | 279 | | /// You must set this property to initialize the control's content. |
| | 280 | | /// Attempting to use the control without setting a valid enum value |
| | 281 | | /// will result in incorrect or empty state. |
| | 282 | | /// </para> |
| | 283 | | /// </remarks> |
| | 284 | | /// <exception cref="ArgumentNullException"> |
| | 285 | | /// Thrown when the provided value is <c>null</c>. |
| | 286 | | /// </exception> |
| | 287 | | /// <exception cref="ArgumentException"> |
| | 288 | | /// Thrown if the value is not an enum or is not decorated with the <see cref="FlagsAttribute"/>. |
| | 289 | | /// </exception> |
| | 290 | | /// <example> |
| | 291 | | /// <code> |
| | 292 | | /// var listBox = new FlagCheckedListBox(); |
| | 293 | | /// listBox.EnumValue = MyFlagsEnum.OptionA | MyFlagsEnum.OptionC; |
| | 294 | | /// var selected = listBox.EnumValue; // Returns combined enum value |
| | 295 | | /// </code> |
| | 296 | | /// </example> |
| | 297 | | /// <value> |
| | 298 | | /// A <see cref="Enum"/> value representing the checked state of the control. |
| | 299 | | /// </value> |
| | 300 | | [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)] |
| | 301 | | public Enum EnumValue |
| | 302 | | { |
| | 303 | | get |
| 40 | 304 | | { |
| 48 | 305 | | var e = Enum.ToObject(enumType, GetCurrentValue()); |
| 48 | 306 | | return (Enum)e; |
| 40 | 307 | | } |
| | 308 | | set |
| 52 | 309 | | { |
| | 310 | | #if NET5_0_OR_GREATER |
| 44 | 311 | | ArgumentNullException.ThrowIfNull(value); |
| | 312 | | #else |
| 16 | 313 | | if (value == null) |
| 16 | 314 | | throw new ArgumentNullException(nameof(value)); |
| | 315 | | #endif |
| 56 | 316 | | enumType = value.GetType(); |
| | 317 | |
|
| 56 | 318 | | if (!Attribute.IsDefined(enumType, typeof(FlagsAttribute))) |
| 20 | 319 | | throw new ArgumentException($"Enum type '{enumType.Name}' must be an enum and have the [Flags] attri |
| 52 | 320 | | Items.Clear(); |
| 52 | 321 | | enumValue = value; // Store the current enum value |
| 52 | 322 | | FillEnumMembers(); // Add items for enum members |
| 52 | 323 | | ApplyEnumValue(); // Check/uncheck items depending on enum value |
| 52 | 324 | | } |
| | 325 | | } |
| | 326 | |
|
| | 327 | | /// <summary> |
| | 328 | | /// Gets or sets the <see cref="EnumConverter"/> used to control how the enum |
| | 329 | | /// values are displayed in the list. |
| | 330 | | /// </summary> |
| | 331 | | /// <remarks> |
| | 332 | | /// This property allows you to provide a custom converter that defines |
| | 333 | | /// how enum values are rendered in the UI—for example, displaying localized |
| | 334 | | /// or user-friendly names instead of the raw enum identifiers. |
| | 335 | | /// |
| | 336 | | /// If no converter is set, the enum field names are used as-is. |
| | 337 | | /// This is especially useful when the enum values are annotated with custom |
| | 338 | | /// attributes (e.g., <c>EnumTextAttribute</c>) and you want those descriptions |
| | 339 | | /// to be shown in the UI. |
| | 340 | | /// |
| | 341 | | /// This property should be assigned before setting <see cref="EnumValue"/>, |
| | 342 | | /// as it affects how the list is populated. |
| | 343 | | /// </remarks> |
| | 344 | | /// <value> |
| | 345 | | /// A custom <see cref="EnumConverter"/> instance for customizing enum display. |
| | 346 | | /// </value> |
| | 347 | | /// <example> |
| | 348 | | /// <code> |
| | 349 | | /// var listBox = new FlagCheckedListBox(); |
| | 350 | | /// listBox.Converter = new EnumTextConverter(typeof(MyFlagsEnum)); |
| | 351 | | /// listBox.EnumValue = MyFlagsEnum.OptionA | MyFlagsEnum.OptionB; |
| | 352 | | /// </code> |
| | 353 | | /// </example> |
| | 354 | | [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)] |
| | 355 | | public EnumConverter Converter |
| | 356 | | { |
| 284 | 357 | | get; set; |
| | 358 | | } |
| | 359 | |
|
| | 360 | | /// <summary> |
| | 361 | | /// Gets or sets the composite enum value represented by the checked items, |
| | 362 | | /// in a non-generic interface-friendly way. |
| | 363 | | /// </summary> |
| | 364 | | [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)] |
| | 365 | | public object Value |
| | 366 | | { |
| 20 | 367 | | get => EnumValue; |
| 24 | 368 | | set => EnumValue = value is Enum e ? e : throw new ArgumentException("Value must be an enum"); |
| | 369 | | } |
| | 370 | |
|
| | 371 | | /// <summary> |
| | 372 | | /// Gets or sets the type descriptor context in which the control is being used. |
| | 373 | | /// </summary> |
| | 374 | | [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)] |
| | 375 | | public ITypeDescriptorContext Context |
| | 376 | | { |
| 104 | 377 | | get; |
| 4 | 378 | | set; |
| | 379 | | } |
| | 380 | |
|
| | 381 | | /// <summary> |
| | 382 | | /// Gets or sets the culture to use for localization or formatting. |
| | 383 | | /// </summary> |
| | 384 | | [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)] |
| | 385 | | public CultureInfo Culture |
| | 386 | | { |
| 104 | 387 | | get; |
| 4 | 388 | | set; |
| | 389 | | } |
| | 390 | | } |
| | 391 | | } |