Code:
/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Core / CSharp / System / Windows / Input / Command / CommandBinding.cs / 1305600 / CommandBinding.cs
//---------------------------------------------------------------------------- // // Copyright (C) Microsoft Corporation. All rights reserved. // //--------------------------------------------------------------------------- using System; using System.ComponentModel; using System.Windows; using System.Windows.Markup; using MS.Internal; using System.Security; using System.Security.Permissions; namespace System.Windows.Input { ////// CommandBinding - Command-EventHandlers map /// CommandBinding acts like a map for EventHandlers and Commands. /// PreviewExecute/Execute, PreviewCanExecute/CanExecute handlers /// can be added at CommandBinding which will exist at Element level /// in the form of a Collection and will be invoked when the system /// is routing the corresponding RoutedEvents. /// public class CommandBinding { #region Constructors ////// Default Constructor - required to allow creation from markup /// public CommandBinding() { } ////// Constructor /// /// Command associated with this binding. public CommandBinding(ICommand command) : this(command, null, null) { } ////// Constructor /// /// Command associated with this binding. /// Handler associated with executing the command. public CommandBinding(ICommand command, ExecutedRoutedEventHandler executed) : this(command, executed, null) { } ////// Constructor /// /// Command associated with this binding. /// Handler associated with executing the command. /// Handler associated with determining if the command can execute. public CommandBinding(ICommand command, ExecutedRoutedEventHandler executed, CanExecuteRoutedEventHandler canExecute) { if (command == null) { throw new ArgumentNullException("command"); } _command = command; if (executed != null) { Executed += executed; } if (canExecute != null) { CanExecute += canExecute; } } #endregion #region Public Properties ////// Command associated with this binding /// [Localizability(LocalizationCategory.NeverLocalize)] // cannot be localized public ICommand Command { get { return _command; } set { if (value == null) { throw new ArgumentNullException("value"); } _command = value; } } #endregion #region Public Events ////// Called before the command is executed. /// public event ExecutedRoutedEventHandler PreviewExecuted; ////// Called when the command is executed. /// public event ExecutedRoutedEventHandler Executed; ////// Called before determining if the command can be executed. /// public event CanExecuteRoutedEventHandler PreviewCanExecute; ////// Called to determine if the command can be executed. /// public event CanExecuteRoutedEventHandler CanExecute; #endregion #region Implementation ////// Calls the CanExecute or PreviewCanExecute event based on the event argument's RoutedEvent. /// /// The sender of the event. /// Event arguments. internal void OnCanExecute(object sender, CanExecuteRoutedEventArgs e) { if (!e.Handled) { if (e.RoutedEvent == CommandManager.CanExecuteEvent) { if (CanExecute != null) { CanExecute(sender, e); if (e.CanExecute) { e.Handled = true; } } else if (!e.CanExecute) { // If there is an Executed handler, then the command can be executed. if (Executed != null) { e.CanExecute = true; e.Handled = true; } } } else // e.RoutedEvent == CommandManager.PreviewCanExecuteEvent { if (PreviewCanExecute != null) { PreviewCanExecute(sender, e); if (e.CanExecute) { e.Handled = true; } } } } } private bool CheckCanExecute(object sender, ExecutedRoutedEventArgs e) { CanExecuteRoutedEventArgs canExecuteArgs = new CanExecuteRoutedEventArgs(e.Command, e.Parameter); canExecuteArgs.RoutedEvent = CommandManager.CanExecuteEvent; // Since we don't actually raise this event, we have to explicitly set the source. canExecuteArgs.Source = e.OriginalSource; canExecuteArgs.OverrideSource(e.Source); OnCanExecute(sender, canExecuteArgs); return canExecuteArgs.CanExecute; } ////// Calls Executed or PreviewExecuted based on the event argument's RoutedEvent. /// /// The sender of the event. /// Event arguments. internal void OnExecuted(object sender, ExecutedRoutedEventArgs e) { if (!e.Handled) { if (e.RoutedEvent == CommandManager.ExecutedEvent) { if (Executed != null) { if (CheckCanExecute(sender, e)) { Executed(sender, e); e.Handled = true; } } } else // e.RoutedEvent == CommandManager.PreviewExecutedEvent { if (PreviewExecuted != null) { if (CheckCanExecute(sender, e)) { PreviewExecuted(sender, e); e.Handled = true; } } } } } #endregion #region Data private ICommand _command; #endregion } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- ArithmeticException.cs
- SrgsRuleRef.cs
- StreamWithDictionary.cs
- CachedCompositeFamily.cs
- PointCollection.cs
- DelayedRegex.cs
- ArrayList.cs
- QilInvokeLateBound.cs
- QilInvokeLateBound.cs
- CodeMemberEvent.cs
- MobileTextWriter.cs
- TransactionManager.cs
- HttpServerVarsCollection.cs
- PackageProperties.cs
- Base64Stream.cs
- DataControlLinkButton.cs
- DtdParser.cs
- ListMarkerSourceInfo.cs
- X509UI.cs
- DataGridPageChangedEventArgs.cs
- KnownTypesHelper.cs
- MouseDevice.cs
- SqlBulkCopyColumnMapping.cs
- DispatcherExceptionEventArgs.cs
- CheckBox.cs
- RangeExpression.cs
- FormViewDeletedEventArgs.cs
- RawStylusInputCustomDataList.cs
- AtomMaterializer.cs
- InternalPermissions.cs
- XmlSchemaAnnotation.cs
- DbgUtil.cs
- ApplicationServiceHelper.cs
- Char.cs
- IPEndPoint.cs
- SecurityHeader.cs
- elementinformation.cs
- ObjectResult.cs
- Viewport2DVisual3D.cs
- AutoGeneratedFieldProperties.cs
- Screen.cs
- ConnectionManagementElement.cs
- DataFormats.cs
- NamespaceInfo.cs
- SignatureSummaryDialog.cs
- LineMetrics.cs
- EmbeddedMailObject.cs
- CompressionTracing.cs
- HScrollBar.cs
- mda.cs
- ContractNamespaceAttribute.cs
- CodeDelegateCreateExpression.cs
- XmlComment.cs
- Roles.cs
- MessageSecurityOverHttp.cs
- TraceRecord.cs
- JsonReaderDelegator.cs
- TableItemStyle.cs
- EventListenerClientSide.cs
- ArrayWithOffset.cs
- EdmProperty.cs
- PropertyChangingEventArgs.cs
- AuthorizationRule.cs
- Currency.cs
- GeneratedView.cs
- TemplatedAdorner.cs
- ColumnMapCopier.cs
- DispatcherBuilder.cs
- AccessViolationException.cs
- DBParameter.cs
- PathParser.cs
- Restrictions.cs
- ListViewItem.cs
- SizeChangedInfo.cs
- DataPagerFieldCollection.cs
- SafeFindHandle.cs
- recordstatefactory.cs
- CompilerGeneratedAttribute.cs
- SoapMessage.cs
- TreeViewHitTestInfo.cs
- UnionCodeGroup.cs
- FeatureAttribute.cs
- StructureChangedEventArgs.cs
- DispatcherSynchronizationContext.cs
- ReadOnlyHierarchicalDataSource.cs
- ScrollEvent.cs
- Size.cs
- WinEventHandler.cs
- HtmlAnchor.cs
- EventManager.cs
- WebAdminConfigurationHelper.cs
- DataRowCollection.cs
- PositiveTimeSpanValidatorAttribute.cs
- Graph.cs
- RuntimeWrappedException.cs
- DiagnosticTraceSource.cs
- entityreference_tresulttype.cs
- HttpResponseWrapper.cs
- WebDescriptionAttribute.cs
- DynamicRouteExpression.cs