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
- SemanticBasicElement.cs
- ClientCredentials.cs
- RowUpdatedEventArgs.cs
- DataSpaceManager.cs
- EventListener.cs
- SoapSchemaMember.cs
- PlatformCulture.cs
- _ShellExpression.cs
- WmiPutTraceRecord.cs
- XmlILConstructAnalyzer.cs
- AdornerPresentationContext.cs
- Command.cs
- RegionIterator.cs
- DesignerRegionMouseEventArgs.cs
- Collection.cs
- RuleRefElement.cs
- EntityConnectionStringBuilderItem.cs
- BaseAppDomainProtocolHandler.cs
- DbInsertCommandTree.cs
- NetworkCredential.cs
- Stylus.cs
- SystemIPv4InterfaceProperties.cs
- PropertyTab.cs
- Enum.cs
- Hyperlink.cs
- ReferentialConstraint.cs
- FormatConvertedBitmap.cs
- CachedFontFamily.cs
- VerificationException.cs
- TemplateBaseAction.cs
- InheritanceContextHelper.cs
- ListItemCollection.cs
- RenderData.cs
- HitTestResult.cs
- SQLInt64Storage.cs
- DateTimeParse.cs
- PropertySourceInfo.cs
- PropertyChangingEventArgs.cs
- DependencyProperty.cs
- BooleanProjectedSlot.cs
- TransportSecurityProtocolFactory.cs
- QilCloneVisitor.cs
- InputReport.cs
- SettingsPropertyIsReadOnlyException.cs
- DescendantBaseQuery.cs
- DataGridRowHeaderAutomationPeer.cs
- processwaithandle.cs
- NumericUpDownAcceleration.cs
- WebPartsPersonalizationAuthorization.cs
- SettingsProviderCollection.cs
- WindowsListViewGroupSubsetLink.cs
- SecurityTokenResolver.cs
- RowBinding.cs
- ExceptionHandler.cs
- ReaderContextStackData.cs
- WebWorkflowRole.cs
- ResourcesGenerator.cs
- DependencyProperty.cs
- Version.cs
- ClientUtils.cs
- LicFileLicenseProvider.cs
- BaseParagraph.cs
- DoubleKeyFrameCollection.cs
- DataRowExtensions.cs
- DetailsViewCommandEventArgs.cs
- DeferredElementTreeState.cs
- SamlEvidence.cs
- TableStyle.cs
- ProviderSettings.cs
- WebPartEditorCancelVerb.cs
- TabPanel.cs
- ObjectNotFoundException.cs
- ListViewPagedDataSource.cs
- ToolTipAutomationPeer.cs
- sqlcontext.cs
- DataGridLengthConverter.cs
- RSAPKCS1KeyExchangeFormatter.cs
- PageCatalogPart.cs
- updatecommandorderer.cs
- DataGridViewCellConverter.cs
- CheckBoxFlatAdapter.cs
- updatecommandorderer.cs
- NativeWindow.cs
- TreeView.cs
- ManifestResourceInfo.cs
- NetworkStream.cs
- BitmapSourceSafeMILHandle.cs
- ClientTarget.cs
- CharAnimationBase.cs
- ScaleTransform3D.cs
- HttpListenerContext.cs
- MasterPageCodeDomTreeGenerator.cs
- TableRow.cs
- PackageFilter.cs
- PrintPreviewGraphics.cs
- _OverlappedAsyncResult.cs
- SortQuery.cs
- BasicHttpSecurityElement.cs
- _DomainName.cs
- RegisteredScript.cs