Code:
/ Net / Net / 3.5.50727.3053 / DEVDIV / depot / DevDiv / releases / Orcas / SP / wpf / src / Framework / System / Windows / Controls / ItemsPresenter.cs / 2 / ItemsPresenter.cs
//---------------------------------------------------------------------------- // //// Copyright (C) Microsoft Corporation. All rights reserved. // // // Description: ItemsPresenter object - site of the panel for layout of groups or items. // // Specs: http://avalon/connecteddata/M5%20General%20Docs/Data%20Styling.mht // //--------------------------------------------------------------------------- using System; using System.Collections; using System.Diagnostics; using System.Windows.Media; using MS.Internal; using MS.Internal.Data; // WeakRefKey namespace System.Windows.Controls { ////// An ItemsPresenter marks the site (in a style) of the panel that controls /// layout of groups or items. /// [Localizability(LocalizationCategory.NeverLocalize)] public class ItemsPresenter : FrameworkElement { //----------------------------------------------------- // // Public Methods // //----------------------------------------------------- ////// Called when the Template's tree is about to be generated /// internal override void OnPreApplyTemplate() { base.OnPreApplyTemplate(); AttachToOwner(); } ////// This is the virtual that sub-classes must override if they wish to get /// notified that the template tree has been created. /// public override void OnApplyTemplate() { // verify that the template produced a panel with no children Panel panel = GetVisualChild(0) as Panel; if (panel == null || VisualTreeHelper.GetChildrenCount(panel) > 0) throw new InvalidOperationException(SR.Get(SRID.ItemsPanelNotSingleNode)); base.OnApplyTemplate(); } //------------------------------------------------------ // // Protected Methods // //----------------------------------------------------- ////// Override of /// Constraint size is an "upper limit" that the return value should not exceed. ///. /// The ItemsPresenter's desired size. protected override Size MeasureOverride(Size constraint) { return Helper.MeasureElementWithSingleChild(this, constraint); } ////// Override of /// Size the ItemsPresenter will assume. protected override Size ArrangeOverride(Size arrangeSize) { return Helper.ArrangeElementWithSingleChild(this, arrangeSize); } //------------------------------------------------------ // // Internal Properties // //------------------------------------------------------ internal ItemsControl Owner { get { return _owner; } } internal ItemContainerGenerator Generator { get { return _generator; } } // Internal Helper so the FrameworkElement could see this property internal override FrameworkTemplate TemplateInternal { get { return Template; } } // Internal Helper so the FrameworkElement could see the template cache internal override FrameworkTemplate TemplateCache { get { return _templateCache; } set { _templateCache = (ItemsPanelTemplate)value; } } ///. /// /// TemplateProperty /// internal static readonly DependencyProperty TemplateProperty = DependencyProperty.Register( "Template", typeof(ItemsPanelTemplate), typeof(ItemsPresenter), new FrameworkPropertyMetadata( (ItemsPanelTemplate) null, // default value FrameworkPropertyMetadataOptions.AffectsMeasure, new PropertyChangedCallback(OnTemplateChanged))); ////// Template Property /// private ItemsPanelTemplate Template { get { return _templateCache; } set { SetValue(TemplateProperty, value); } } // Internal helper so FrameworkElement could see call the template changed virtual internal override void OnTemplateChangedInternal(FrameworkTemplate oldTemplate, FrameworkTemplate newTemplate) { OnTemplateChanged((ItemsPanelTemplate)oldTemplate, (ItemsPanelTemplate)newTemplate); } // Property invalidation callback invoked when TemplateProperty is invalidated private static void OnTemplateChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { ItemsPresenter ip = (ItemsPresenter) d; StyleHelper.UpdateTemplateCache(ip, (FrameworkTemplate) e.OldValue, (FrameworkTemplate) e.NewValue, TemplateProperty); } ////// Template has changed /// ////// When a Template changes, the VisualTree is removed. The new Template's /// VisualTree will be created when ApplyTemplate is called /// /// The old Template /// The new Template protected virtual void OnTemplateChanged(ItemsPanelTemplate oldTemplate, ItemsPanelTemplate newTemplate) { } //----------------------------------------------------- // // Internal Methods // //------------------------------------------------------ internal static ItemsPresenter FromPanel(Panel panel) { if (panel == null) return null; return panel.TemplatedParent as ItemsPresenter; } internal static ItemsPresenter FromGroupItem(GroupItem groupItem) { if (groupItem == null) return null; Visual parent = VisualTreeHelper.GetParent(groupItem) as Visual; if (parent == null) return null; return VisualTreeHelper.GetParent(parent) as ItemsPresenter; } internal override void OnAncestorChanged() { if (TemplatedParent == null) { UseGenerator(null); ClearPanel(); } base.OnAncestorChanged(); } //----------------------------------------------------- // // Private Methods // //----------------------------------------------------- // initialize (called during measure, from ApplyTemplate) void AttachToOwner() { ItemsControl owner = this.TemplatedParent as ItemsControl; ItemContainerGenerator generator; if (owner != null) { // top-level presenter - get information from ItemsControl generator = owner.ItemContainerGenerator; } else { // subgroup presenter - get information from GroupItem GroupItem parentGI = this.TemplatedParent as GroupItem; ItemsPresenter parentIP = FromGroupItem(parentGI); if (parentIP != null) owner = parentIP.Owner; generator = (parentGI != null) ? parentGI.Generator : null; } _owner = owner; UseGenerator(generator); // create the panel, based either on ItemsControl.ItemsPanel or GroupStyle.Panel GroupStyle groupStyle = (_generator != null) ? _generator.GroupStyle : null; Template = (groupStyle != null) ? groupStyle.Panel : (_owner != null) ? _owner.ItemsPanel : null; } void UseGenerator(ItemContainerGenerator generator) { if (generator == _generator) return; if (_generator != null) _generator.PanelChanged -= new EventHandler(OnPanelChanged); _generator = generator; if (_generator != null) _generator.PanelChanged += new EventHandler(OnPanelChanged); } private void OnPanelChanged(object sender, EventArgs e) { // something has changed that affects the ItemsPresenter. // Re-measure. This will recalculate everything from scratch. InvalidateMeasure(); // // If we're under a ScrollViewer then its ScrollContentPresenter needs to // be updated to work with the new panel. // ScrollViewer parent = Parent as ScrollViewer; if (parent != null) { // If our logical parent is a ScrollViewer then the visual parent is a ScrollContentPresenter. ScrollContentPresenter scp = VisualTreeHelper.GetParent(this) as ScrollContentPresenter; if (scp != null) { scp.HookupScrollingComponents(); } } } // workaround, pending bug 953483. The panel is // being removed from the tree, so it should release // its resources (chiefly - stop listening for generator's // ItemsChanged event). Until there's a mechanism for // this, just mark the panel as a non-ItemsHost, so // that the next time it gets ItemsChanged it will // stop listening. (See also bug 942265) private void ClearPanel() { Panel oldPanel = (this.VisualChildrenCount > 0) ? this.GetVisualChild(0) as Panel : null; Type type = null; if( Template != null ) { // Get the type of the template content's root // Is this a FEF-based template? if( Template.VisualTree != null ) { type = Template.VisualTree.Type; } // Or, is it a (non-empty) Baml-based template? else if( !Template.OptimizedTemplateContent.IsEmpty ) { type = Template.OptimizedTemplateContent.RootType; } } if (oldPanel != null && oldPanel.GetType() == type) { oldPanel.IsItemsHost = false; } } //----------------------------------------------------- // // Private Fields // //------------------------------------------------------ ItemsControl _owner; ItemContainerGenerator _generator; ItemsPanelTemplate _templateCache; } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved. //---------------------------------------------------------------------------- // //// Copyright (C) Microsoft Corporation. All rights reserved. // // // Description: ItemsPresenter object - site of the panel for layout of groups or items. // // Specs: http://avalon/connecteddata/M5%20General%20Docs/Data%20Styling.mht // //--------------------------------------------------------------------------- using System; using System.Collections; using System.Diagnostics; using System.Windows.Media; using MS.Internal; using MS.Internal.Data; // WeakRefKey namespace System.Windows.Controls { ////// An ItemsPresenter marks the site (in a style) of the panel that controls /// layout of groups or items. /// [Localizability(LocalizationCategory.NeverLocalize)] public class ItemsPresenter : FrameworkElement { //----------------------------------------------------- // // Public Methods // //----------------------------------------------------- ////// Called when the Template's tree is about to be generated /// internal override void OnPreApplyTemplate() { base.OnPreApplyTemplate(); AttachToOwner(); } ////// This is the virtual that sub-classes must override if they wish to get /// notified that the template tree has been created. /// public override void OnApplyTemplate() { // verify that the template produced a panel with no children Panel panel = GetVisualChild(0) as Panel; if (panel == null || VisualTreeHelper.GetChildrenCount(panel) > 0) throw new InvalidOperationException(SR.Get(SRID.ItemsPanelNotSingleNode)); base.OnApplyTemplate(); } //------------------------------------------------------ // // Protected Methods // //----------------------------------------------------- ////// Override of /// Constraint size is an "upper limit" that the return value should not exceed. ///. /// The ItemsPresenter's desired size. protected override Size MeasureOverride(Size constraint) { return Helper.MeasureElementWithSingleChild(this, constraint); } ////// Override of /// Size the ItemsPresenter will assume. protected override Size ArrangeOverride(Size arrangeSize) { return Helper.ArrangeElementWithSingleChild(this, arrangeSize); } //------------------------------------------------------ // // Internal Properties // //------------------------------------------------------ internal ItemsControl Owner { get { return _owner; } } internal ItemContainerGenerator Generator { get { return _generator; } } // Internal Helper so the FrameworkElement could see this property internal override FrameworkTemplate TemplateInternal { get { return Template; } } // Internal Helper so the FrameworkElement could see the template cache internal override FrameworkTemplate TemplateCache { get { return _templateCache; } set { _templateCache = (ItemsPanelTemplate)value; } } ///. /// /// TemplateProperty /// internal static readonly DependencyProperty TemplateProperty = DependencyProperty.Register( "Template", typeof(ItemsPanelTemplate), typeof(ItemsPresenter), new FrameworkPropertyMetadata( (ItemsPanelTemplate) null, // default value FrameworkPropertyMetadataOptions.AffectsMeasure, new PropertyChangedCallback(OnTemplateChanged))); ////// Template Property /// private ItemsPanelTemplate Template { get { return _templateCache; } set { SetValue(TemplateProperty, value); } } // Internal helper so FrameworkElement could see call the template changed virtual internal override void OnTemplateChangedInternal(FrameworkTemplate oldTemplate, FrameworkTemplate newTemplate) { OnTemplateChanged((ItemsPanelTemplate)oldTemplate, (ItemsPanelTemplate)newTemplate); } // Property invalidation callback invoked when TemplateProperty is invalidated private static void OnTemplateChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) { ItemsPresenter ip = (ItemsPresenter) d; StyleHelper.UpdateTemplateCache(ip, (FrameworkTemplate) e.OldValue, (FrameworkTemplate) e.NewValue, TemplateProperty); } ////// Template has changed /// ////// When a Template changes, the VisualTree is removed. The new Template's /// VisualTree will be created when ApplyTemplate is called /// /// The old Template /// The new Template protected virtual void OnTemplateChanged(ItemsPanelTemplate oldTemplate, ItemsPanelTemplate newTemplate) { } //----------------------------------------------------- // // Internal Methods // //------------------------------------------------------ internal static ItemsPresenter FromPanel(Panel panel) { if (panel == null) return null; return panel.TemplatedParent as ItemsPresenter; } internal static ItemsPresenter FromGroupItem(GroupItem groupItem) { if (groupItem == null) return null; Visual parent = VisualTreeHelper.GetParent(groupItem) as Visual; if (parent == null) return null; return VisualTreeHelper.GetParent(parent) as ItemsPresenter; } internal override void OnAncestorChanged() { if (TemplatedParent == null) { UseGenerator(null); ClearPanel(); } base.OnAncestorChanged(); } //----------------------------------------------------- // // Private Methods // //----------------------------------------------------- // initialize (called during measure, from ApplyTemplate) void AttachToOwner() { ItemsControl owner = this.TemplatedParent as ItemsControl; ItemContainerGenerator generator; if (owner != null) { // top-level presenter - get information from ItemsControl generator = owner.ItemContainerGenerator; } else { // subgroup presenter - get information from GroupItem GroupItem parentGI = this.TemplatedParent as GroupItem; ItemsPresenter parentIP = FromGroupItem(parentGI); if (parentIP != null) owner = parentIP.Owner; generator = (parentGI != null) ? parentGI.Generator : null; } _owner = owner; UseGenerator(generator); // create the panel, based either on ItemsControl.ItemsPanel or GroupStyle.Panel GroupStyle groupStyle = (_generator != null) ? _generator.GroupStyle : null; Template = (groupStyle != null) ? groupStyle.Panel : (_owner != null) ? _owner.ItemsPanel : null; } void UseGenerator(ItemContainerGenerator generator) { if (generator == _generator) return; if (_generator != null) _generator.PanelChanged -= new EventHandler(OnPanelChanged); _generator = generator; if (_generator != null) _generator.PanelChanged += new EventHandler(OnPanelChanged); } private void OnPanelChanged(object sender, EventArgs e) { // something has changed that affects the ItemsPresenter. // Re-measure. This will recalculate everything from scratch. InvalidateMeasure(); // // If we're under a ScrollViewer then its ScrollContentPresenter needs to // be updated to work with the new panel. // ScrollViewer parent = Parent as ScrollViewer; if (parent != null) { // If our logical parent is a ScrollViewer then the visual parent is a ScrollContentPresenter. ScrollContentPresenter scp = VisualTreeHelper.GetParent(this) as ScrollContentPresenter; if (scp != null) { scp.HookupScrollingComponents(); } } } // workaround, pending bug 953483. The panel is // being removed from the tree, so it should release // its resources (chiefly - stop listening for generator's // ItemsChanged event). Until there's a mechanism for // this, just mark the panel as a non-ItemsHost, so // that the next time it gets ItemsChanged it will // stop listening. (See also bug 942265) private void ClearPanel() { Panel oldPanel = (this.VisualChildrenCount > 0) ? this.GetVisualChild(0) as Panel : null; Type type = null; if( Template != null ) { // Get the type of the template content's root // Is this a FEF-based template? if( Template.VisualTree != null ) { type = Template.VisualTree.Type; } // Or, is it a (non-empty) Baml-based template? else if( !Template.OptimizedTemplateContent.IsEmpty ) { type = Template.OptimizedTemplateContent.RootType; } } if (oldPanel != null && oldPanel.GetType() == type) { oldPanel.IsItemsHost = false; } } //----------------------------------------------------- // // Private Fields // //------------------------------------------------------ ItemsControl _owner; ItemContainerGenerator _generator; ItemsPanelTemplate _templateCache; } } // 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
- TraceSection.cs
- IgnoreFlushAndCloseStream.cs
- BoundPropertyEntry.cs
- StreamReader.cs
- SinglePhaseEnlistment.cs
- Int32CAMarshaler.cs
- TemplateXamlParser.cs
- ReadWriteControlDesigner.cs
- ListViewPagedDataSource.cs
- SqlError.cs
- SecurityMode.cs
- DataGridRow.cs
- GroupBox.cs
- ToolStripLocationCancelEventArgs.cs
- EventDriven.cs
- CodeFieldReferenceExpression.cs
- FixedSOMLineRanges.cs
- PackageDigitalSignatureManager.cs
- UnmanagedMemoryStream.cs
- SequentialUshortCollection.cs
- ComponentEvent.cs
- SoapFaultCodes.cs
- PlainXmlWriter.cs
- FontSource.cs
- MessageQueuePermissionEntry.cs
- MeasurementDCInfo.cs
- DataGrid.cs
- HandlerFactoryWrapper.cs
- ProxyWebPart.cs
- _TransmitFileOverlappedAsyncResult.cs
- MultiTrigger.cs
- SchemaCollectionCompiler.cs
- HttpHandlerActionCollection.cs
- SafeRegistryHandle.cs
- Splitter.cs
- DataTemplate.cs
- entityreference_tresulttype.cs
- OraclePermissionAttribute.cs
- SiteMapPath.cs
- SuppressMergeCheckAttribute.cs
- NavigationHelper.cs
- SourceElementsCollection.cs
- Point3DKeyFrameCollection.cs
- AspNetHostingPermission.cs
- GenericsInstances.cs
- MaterialGroup.cs
- ClientTargetCollection.cs
- FeatureAttribute.cs
- InputBinding.cs
- InertiaRotationBehavior.cs
- FreeFormDragDropManager.cs
- BitStack.cs
- COM2Properties.cs
- RelationshipEnd.cs
- LineInfo.cs
- ApplyTemplatesAction.cs
- BaseCodeDomTreeGenerator.cs
- ByteRangeDownloader.cs
- CellCreator.cs
- filewebrequest.cs
- PartialCachingControl.cs
- ActivityBindForm.Designer.cs
- IriParsingElement.cs
- TypeHelper.cs
- GenericPrincipal.cs
- HttpPostLocalhostServerProtocol.cs
- SplayTreeNode.cs
- ProjectionCamera.cs
- OpenFileDialog.cs
- UnsafeNativeMethods.cs
- FormatterServices.cs
- SQLDecimal.cs
- EntityDataSourceSelectedEventArgs.cs
- SmtpCommands.cs
- input.cs
- ButtonBase.cs
- CaseKeyBox.xaml.cs
- HtmlDocument.cs
- ClientConfigurationSystem.cs
- ExplicitDiscriminatorMap.cs
- EventBookmark.cs
- SetterBaseCollection.cs
- TreeView.cs
- SourceInterpreter.cs
- TextEditorContextMenu.cs
- ChildDocumentBlock.cs
- NameValueSectionHandler.cs
- securitymgrsite.cs
- ViewGenResults.cs
- ExponentialEase.cs
- OnOperation.cs
- DocumentScope.cs
- FacetChecker.cs
- ItemCollectionEditor.cs
- IOThreadTimer.cs
- FlatButtonAppearance.cs
- AvTraceFormat.cs
- ScrollItemPattern.cs
- ToolStripItemCollection.cs
- XmlSignatureManifest.cs