Code:
/ Dotnetfx_Vista_SP2 / Dotnetfx_Vista_SP2 / 8.0.50727.4016 / DEVDIV / depot / DevDiv / releases / Orcas / QFE / wpf / src / Framework / System / Windows / Controls / ItemsPresenter.cs / 1 / 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
- XmlAnyAttributeAttribute.cs
- TransactionException.cs
- PackWebRequest.cs
- XComponentModel.cs
- VisualTreeHelper.cs
- TreeIterators.cs
- NameTable.cs
- ReferenceEqualityComparer.cs
- AttachedAnnotation.cs
- OleDbMetaDataFactory.cs
- PointConverter.cs
- SchemaAttDef.cs
- CompModSwitches.cs
- ACL.cs
- XPathParser.cs
- GridView.cs
- RenderingEventArgs.cs
- XmlSchemaRedefine.cs
- FormsAuthentication.cs
- WebPart.cs
- CommentEmitter.cs
- BaseTemplateBuildProvider.cs
- CultureInfo.cs
- UnsafeNativeMethods.cs
- ObservableDictionary.cs
- Tile.cs
- PointAnimationUsingKeyFrames.cs
- MimeTypeAttribute.cs
- SizeAnimationClockResource.cs
- WebControlToolBoxItem.cs
- RelativeSource.cs
- DrawListViewSubItemEventArgs.cs
- SaveFileDialog.cs
- UdpUtility.cs
- DynamicExpression.cs
- EntityContainer.cs
- Sentence.cs
- OrderedDictionary.cs
- Asn1Utilities.cs
- ObjectDataSourceView.cs
- CngKey.cs
- baseaxisquery.cs
- InstanceDataCollection.cs
- EventPrivateKey.cs
- MetadataItemEmitter.cs
- TypeCodeDomSerializer.cs
- StylusCaptureWithinProperty.cs
- FastEncoder.cs
- NamedObject.cs
- EnumerableRowCollectionExtensions.cs
- SqlGenerator.cs
- ParserHooks.cs
- ReadOnlyHierarchicalDataSource.cs
- DescendentsWalker.cs
- CasesDictionary.cs
- PointLight.cs
- PreviewKeyDownEventArgs.cs
- WebPartConnectVerb.cs
- ContentValidator.cs
- XmlReader.cs
- ParameterToken.cs
- coordinator.cs
- ConfigurationElementProperty.cs
- GAC.cs
- ModelItemExtensions.cs
- DataGridViewRowHeaderCell.cs
- CompositionTarget.cs
- GridItemPatternIdentifiers.cs
- XmlCharType.cs
- TableItemPattern.cs
- MetadataItemSerializer.cs
- SerializationInfoEnumerator.cs
- Screen.cs
- AutoGeneratedFieldProperties.cs
- InheritanceAttribute.cs
- ConfigurationSectionGroup.cs
- _ChunkParse.cs
- DataGridViewColumnTypeEditor.cs
- CompensatableSequenceActivity.cs
- RecognizedWordUnit.cs
- FastEncoder.cs
- FixedTextView.cs
- SqlRecordBuffer.cs
- ConnectionProviderAttribute.cs
- Animatable.cs
- CreateUserWizard.cs
- TypeGeneratedEventArgs.cs
- SafeRegistryKey.cs
- InfoCardAsymmetricCrypto.cs
- UnsafeNativeMethods.cs
- ApplicationInfo.cs
- WindowsProgressbar.cs
- SizeChangedInfo.cs
- ControlCachePolicy.cs
- TransactedBatchContext.cs
- EdmSchemaError.cs
- BamlLocalizableResourceKey.cs
- UpdatePanelTriggerCollection.cs
- FormsAuthenticationEventArgs.cs
- PrivilegedConfigurationManager.cs