class/System.Windows/System.Windows.Automation.Peers/FrameworkElementAutomationPeer.cs

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   9 // The above copyright notice and this permission notice shall be
  10 // included in all copies or substantial portions of the Software.
  11 //
  12 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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  14 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  15 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
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  17 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  18 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  19 //
  20 // Copyright (c) 2008 Novell, Inc. (http://www.novell.com)
  21 //
  22 // Contact:
  23 //   Moonlight Team (moonlight-list@lists.ximian.com)
  24 //
  25
  26 using System;
  27 using System.Collections.Generic;
  28 using System.Windows;
  29 using System.Windows.Automation;
  30 using System.Windows.Controls;
  31 using System.Windows.Markup;
  32 using System.Windows.Media;
  33 using System.Linq;
  34
  35 namespace System.Windows.Automation.Peers {
  36
  37         public class FrameworkElementAutomationPeer : AutomationPeer {
  38
  39                 private FrameworkElement owner;
  40
  41                 public FrameworkElementAutomationPeer (FrameworkElement owner)
  42                 {
  43                         if (owner == null)
  44                                 throw new NullReferenceException ("owner");
  45                         this.owner = owner;
  46
  47                         // Default Automation events
  48                         owner.GotFocus += (o, a) => {
  49                                 RaisePropertyChangedEvent (AutomationElementIdentifiers.HasKeyboardFocusProperty,
  50                                                            false,
  51                                                            true);
  52                         };
  53                         owner.LostFocus += (o, a) => {
  54                                 RaisePropertyChangedEvent (AutomationElementIdentifiers.HasKeyboardFocusProperty,
  55                                                            true,
  56                                                            false);
  57                         };
  58
  59                         owner.SizeChanged += (o, s) => {
  60                                 Point location = GetLocation (owner);
  61                                 RaisePropertyChangedEvent (AutomationElementIdentifiers.BoundingRectangleProperty,
  62                                                            new Rect (0, 0, s.PreviousSize.Width, s.PreviousSize.Height),
  63                                                            new Rect (location.X, location.Y, s.NewSize.Width, s.NewSize.Height));
  64                         };
  65
  66                         Control control = owner as Control;
  67                         if (control != null)
  68                                 control.IsEnabledChanged += (o, e) => {
  69                                         RaisePropertyChangedEvent (AutomationElementIdentifiers.IsEnabledProperty,
  70                                                                    e.OldValue,
  71                                                                    e.NewValue);
  72                                 };
  73                 }
  74
  75                 public UIElement Owner {
  76                         get { return owner; }
  77                 }
  78
  79                 protected override string GetNameCore ()
  80                 {
  81                         return owner.GetValue (AutomationProperties.NameProperty) as string ?? string.Empty;
  82                 }
  83
  84                 protected override string GetItemTypeCore ()
  85                 {
  86                         return owner.GetValue (AutomationProperties.ItemTypeProperty) as string ?? string.Empty;
  87                 }
  88
  89                 protected override AutomationPeer GetLabeledByCore ()
  90                 {
  91                         UIElement labeledBy = owner.GetValue (AutomationProperties.LabeledByProperty) as UIElement;
  92                         if (labeledBy != null)
  93                                 return FrameworkElementAutomationPeer.CreatePeerForElement (labeledBy);
  94                         else
  95                                 return null;
  96                 }
  97
  98                 protected override List<AutomationPeer> GetChildrenCore ()
  99                 {
 100                         return ChildrenCore;
 101                 }
 102
 103                 public override object GetPattern (PatternInterface pattern)
 104                 {
 105                         return null;
 106                 }
 107
 108                 public static AutomationPeer FromElement (UIElement element)
 109                 {
 110                         if (element == null)
 111                                 throw new ArgumentNullException ("element");
 112                         return element.AutomationPeer;
 113                 }
 114
 115                 protected override string GetAcceleratorKeyCore ()
 116                 {
 117                         return owner.GetValue (AutomationProperties.AcceleratorKeyProperty) as string ?? string.Empty;
 118                 }
 119
 120                 protected override string GetAccessKeyCore ()
 121                 {
 122                         return owner.GetValue (AutomationProperties.AccessKeyProperty) as string ?? string.Empty;
 123                 }
 124
 125                 protected override AutomationControlType GetAutomationControlTypeCore ()
 126                 {
 127                         // Some Peers don't override GetAutomationControlTypeCore and return something different to Custom
 128                         // for example: TextBoxAutomationPeer
 129                         return AutomationControlTypeCore.HasValue ? AutomationControlTypeCore.Value : AutomationControlType.Custom;
 130                 }
 131
 132                 protected override string GetAutomationIdCore ()
 133                 {
 134                         return owner.GetValue (AutomationProperties.AutomationIdProperty) as string ?? string.Empty;
 135                 }
 136
 137                 protected override Rect GetBoundingRectangleCore ()
 138                 {
 139                         if (VisualTreeHelper.GetParent (owner) == null)
 140                                 return new Rect (0, 0, 0, 0);
 141
 142                         return GetBoundingRectangleFrom (owner);
 143                 }
 144
 145                 protected override string GetClassNameCore ()
 146                 {
 147                         return ClassNameCore ?? string.Empty;
 148                 }
 149
 150                 protected override Point GetClickablePointCore ()
 151                 {
 152                         return new Point (0, 0);
 153                 }
 154
 155                 protected override string GetHelpTextCore ()
 156                 {
 157                         return owner.GetValue (AutomationProperties.HelpTextProperty) as string ?? string.Empty;
 158                 }
 159
 160                 protected override string GetItemStatusCore ()
 161                 {
 162                         return owner.GetValue (AutomationProperties.ItemStatusProperty) as string ?? string.Empty;
 163                 }
 164
 165                 protected override string GetLocalizedControlTypeCore ()
 166                 {
 167                         // LAMESPEC: http://msdn.microsoft.com/en-us/library/ms743581.aspx
 168                         // "CamelCase" literal values should be "camel case", not "camelcase"
 169                         return GetAutomationControlType ().ToString ().ToLower ();
 170                 }
 171
 172                 protected override AutomationOrientation GetOrientationCore ()
 173                 {
 174                         return AutomationOrientation.None;
 175                 }
 176
 177                 protected override bool HasKeyboardFocusCore ()
 178                 {
 179                         return owner == System.Windows.Input.FocusManager.GetFocusedElement ();
 180                 }
 181
 182                 protected override bool IsContentElementCore ()
 183                 {
 184                         return true;
 185                 }
 186
 187                 protected override bool IsControlElementCore ()
 188                 {
 189                         return true;
 190                 }
 191
 192                 protected override bool IsEnabledCore ()
 193                 {
 194                         Control ownerAsControl = owner as Control;
 195                         if (ownerAsControl != null)
 196                                 return ownerAsControl.IsEnabled;
 197
 198                         // Fall back to default value
 199                         return true;
 200                 }
 201
 202                 protected override bool IsKeyboardFocusableCore ()
 203                 {
 204                         return false;
 205                 }
 206
 207                 protected override bool IsOffscreenCore ()
 208                 {
 209                         return false;
 210                 }
 211
 212                 protected override bool IsPasswordCore ()
 213                 {
 214                         return PasswordCore;
 215                 }
 216
 217                 protected override bool IsRequiredForFormCore ()
 218                 {
 219                         bool? isRequired = (bool?) owner.GetValue (AutomationProperties.IsRequiredForFormProperty);
 220                         return isRequired.HasValue ? isRequired.Value : false;
 221                 }
 222
 223                 protected override void SetFocusCore ()
 224                 {
 225                         Control ownerAsControl = owner as Control;
 226                         if (ownerAsControl != null)
 227                                 ownerAsControl.Focus ();
 228                 }
 229
 230                 public static AutomationPeer CreatePeerForElement (UIElement element)
 231                 {
 232                         if (element == null)
 233                                 throw new ArgumentNullException ("element");
 234                         if (element.AutomationPeer == null) {
 235                                 element.AutomationPeer = element.CreateAutomationPeer ();
 236                                 // We need to cache old values to raise PropertyChanged events
 237                                 // when calling AutomationPeer.InvalidatePeer()
 238                                 if (element.AutomationPeer != null)
 239                                         element.AutomationPeer.CacheMainProperties ();
 240                         }
 241                         return element.AutomationPeer;
 242                 }
 243
 244                 internal override AutomationPeer GetParentCore ()
 245                 {
 246                         return GetParentPeer (owner);
 247                 }
 248
 249                 #region Private Methods
 250
 251                 private AutomationPeer GetParentPeer (FrameworkElement element)
 252                 {
 253                         // We are returning parents of children already instantiated.
 254                         if (element == null)
 255                                 return null;
 256
 257                         FrameworkElement parent = VisualTreeHelper.GetParent (element) as FrameworkElement;
 258                         if (parent == null)
 259                                 return null;
 260
 261                         // Some parents don't return an Automation Peer (for example: Border or Panel subclasses)
 262                         // We need to create the Peer because some Peers return children that don't
 263                         // necesarily return this peer when calling GetParent
 264                         // (for example: ListBox when Template is not null)
 265                         AutomationPeer peer = FrameworkElementAutomationPeer.CreatePeerForElement (parent);
 266                         if (peer == null)
 267                                 return GetParentPeer (parent);
 268                         else
 269                                 return peer;
 270                 }
 271
 272                 #endregion
 273
 274                 #region Internal properties
 275
 276                 // Internal properties used by Peers that don't override XXXXCore and return something else
 277                 // than FrameworkElementAutomationPeer's default value.
 278
 279                 internal virtual AutomationControlType? AutomationControlTypeCore {
 280                         get { return null; }
 281                 }
 282
 283                 internal virtual string ClassNameCore {
 284                         get { return null; }
 285                 }
 286
 287                 internal virtual List<AutomationPeer> ChildrenCore {
 288                         get { return GetChildrenRecursively (owner); }
 289                 }
 290
 291                 internal virtual bool PasswordCore {
 292                         get { return false; }
 293                 }
 294
 295                 #endregion
 296
 297                 #region Internal methods
 298
 299                 internal static List<AutomationPeer> GetChildrenRecursively (UIElement uielement)
 300                 {
 301                         List<AutomationPeer> children = new List<AutomationPeer> ();
 302                         int childrenCount = VisualTreeHelper.GetChildrenCount (uielement);
 303
 304                         for (int child = 0; child < childrenCount; child++) {
 305                                 UIElement element = VisualTreeHelper.GetChild (uielement, child) as UIElement;
 306                                 if (element == null)
 307                                         continue;
 308
 309                                 AutomationPeer peer
 310                                         = FrameworkElementAutomationPeer.CreatePeerForElement (element);
 311                                 if (peer != null)
 312                                         children.Add (peer);
 313                                 else {
 314                                         List<AutomationPeer> returnedChildren
 315                                                 = GetChildrenRecursively (element);
 316                                         if (returnedChildren != null)
 317                                                 children.AddRange (returnedChildren);
 318                                 }
 319                         }
 320
 321                         if (children.Count == 0)
 322                                 return null;
 323
 324                         return children;
 325                 }
 326
 327                 internal Point GetLocation (FrameworkElement owner)
 328                 {
 329                         if (VisualTreeHelper.GetParent (owner) == null)
 330                                 return new Point (0, 0);
 331
 332                         Point point = new Point (0, 0);
 333                         try {
 334                                 // This happens when an item is not visible yet but exists, for
 335                                 // example ListBoxItems in ComboBox when Template is not null
 336                                 point = owner.TransformToVisual (Application.Current.RootVisual).Transform (new Point ());
 337                         } catch (ArgumentException) { }
 338
 339                         return point;
 340                 }
 341
 342                 internal Rect GetBoundingRectangleFrom (FrameworkElement owner)
 343                 {
 344                         Point location = GetLocation (owner);
 345
 346                         double width = (double) owner.GetValue (FrameworkElement.WidthProperty);
 347                         double height = (double) owner.GetValue (FrameworkElement.HeightProperty);
 348
 349                         if (double.IsNaN (width))
 350                                 width = 0;
 351                         if (double.IsNaN (height))
 352                                 height = 0;
 353
 354                         // Some Controls may not be honoring the specified Height or Width and would
 355                         // use a different value, that's why we need to test these properties too,
 356                         // Examples of those Controls are TextBlock and Image.
 357                         if (height == 0)
 358                                 height = (double) owner.GetValue (FrameworkElement.ActualHeightProperty);
 359                         if (width == 0)
 360                                 width = (double) owner.GetValue (FrameworkElement.ActualWidthProperty);
 361
 362                         return new Rect (location.X, location.Y, width, height);
 363                 }
 364
 365                 #endregion
 366         }
 367
 368 }