Class TreeViewPanel

GridViewVirtualizingPanel is used to arrange children into single line.

Inheritance

System.Object

TreeViewPanel

Namespace: Telerik.Windows.Controls.TreeView

Assembly: Telerik.Windows.Controls.Navigation.dll

Syntax

public class TreeViewPanel : VirtualizingPanel, IScrollInfo

Constructors

TreeViewPanel()

Initializes a new instance of the TreeViewPanel class.

Declaration

public TreeViewPanel()

Fields

TreeVirtualizationModeProperty

Attached property for use on the ItemsControl that is the host for the items being presented by this panel. Use this property to modify the virtualization mode. Note that this property can only be set before the panel has been initialized.

Declaration

public static readonly DependencyProperty TreeVirtualizationModeProperty

Field Value

System.Windows.DependencyProperty

VirtualizationModeProperty

Attached property for use on the ItemsControl that is the host for the items being presented by this panel. Use this property to modify the virtualization mode.

Note that this property can only be set before the panel has been initialized.

Declaration

public static readonly DependencyProperty VirtualizationModeProperty

Field Value

System.Windows.DependencyProperty

Properties

CanHorizontallyScroll

GridViewVirtualizingPanel reacts to this property by changing its child measurement algorithm. If scrolling in a dimension, infinite space is allowed the child; otherwise, available size is preserved.

Declaration

public bool CanHorizontallyScroll { get; set; }

Property Value

System.Boolean

CanVerticallyScroll

Declaration

public bool CanVerticallyScroll { get; set; }

Property Value

System.Boolean

ChildDefaultLength

Gets or sets the expected length (width or height) for the items of the panel. This is a dependency property.

Declaration

public double ChildDefaultLength { get; set; }

Property Value

System.Double

Remarks

The value of this property should be as close as possible to the header height of the TreeViewItem.

ExtentHeight

ExtentHeight contains the vertical size of the scrolled content element in 1/96".

Declaration

public double ExtentHeight { get; }

Property Value

System.Double

ExtentWidth

ExtentWidth contains the horizontal size of the scrolled content element in 1/96".

Declaration

public double ExtentWidth { get; }

Property Value

System.Double

HasLogicalOrientation

This property is always false because this panel has only vertical.

Declaration

protected override bool HasLogicalOrientation { get; }

Property Value

System.Boolean

HorizontalOffset

HorizontalOffset is the horizontal offset of the scrolled content in 1/96".

Declaration

public double HorizontalOffset { get; }

Property Value

System.Double

IsVisualCacheEnabled

Determines whether the panel should cache its visual items or not. Caching improves scrolling performance but may affect memory usage.

Declaration

public bool IsVisualCacheEnabled { get; set; }

Property Value

System.Boolean

LogicalOrientation

Orientation of the panel if its layout is in one dimension. Otherwise HasLogicalOrientation is false and LogicalOrientation should be ignored.

Declaration

protected override Orientation LogicalOrientation { get; }

Property Value

System.Windows.Controls.Orientation

ScrollOwner

ScrollOwner is the container that controls any scrollbars, headers, etc... that are dependant on this IScrollInfo's properties.

Declaration

public ScrollViewer ScrollOwner { get; set; }

Property Value

System.Windows.Controls.ScrollViewer

VerticalOffset

VerticalOffset is the vertical offset of the scrolled content in 1/96".

Declaration

public double VerticalOffset { get; }

Property Value

System.Double

ViewportHeight

ViewportHeight contains the vertical size of content's visible range in 1/96" .

Declaration

public double ViewportHeight { get; }

Property Value

System.Double

ViewportWidth

ViewportWidth contains the horizontal size of content's visible range in 1/96".

Declaration

public double ViewportWidth { get; }

Property Value

System.Double

Methods

AddCleanUpVirtualizedItemHandler(DependencyObject, CleanUpVirtualizedItemEventHandler)

Adds a handler for the CleanUpVirtualizedItem attached event.

Declaration

public static void AddCleanUpVirtualizedItemHandler(DependencyObject element, CleanUpVirtualizedItemEventHandler handler)

Parameters

System.Windows.DependencyObject element

DependencyObject that listens to this event.

CleanUpVirtualizedItemEventHandler handler

Event Handler to be added.

ArrangeOverride(Size)

Arranges the override.

Declaration

protected override Size ArrangeOverride(Size finalSize)

Parameters

System.Windows.Size finalSize

Size of the arrange.

Returns

System.Windows.Size

BringIndexIntoView(Int32)

Generates the item at the specified index and calls BringIntoView on it.

Declaration

protected override void BringIndexIntoView(int index)

Parameters

System.Int32 index

Specify the item index that should become visible.

Exceptions

System.ArgumentOutOfRangeException

Thrown if index is out of range.

GetIsVirtualizing(DependencyObject)

Retrieves the value for IsVirtualizingProperty.

Declaration

public static bool GetIsVirtualizing(DependencyObject element)

Parameters

System.Windows.DependencyObject element

The object on which to query the value.

Returns

System.Boolean

True if virtualizing, false otherwise.

GetTreeVirtualizationMode(DependencyObject)

Retrieves the value for TreeVirtualizationModeProperty.

Declaration

public static VirtualizationMode GetTreeVirtualizationMode(DependencyObject element)

Parameters

System.Windows.DependencyObject element

The object on which to query the value.

Returns

VirtualizationMode

The current virtualization mode.

GetVirtualizationMode(DependencyObject)

Retrieves the value for VirtualizationModeProperty.

Declaration

public static VirtualizationMode GetVirtualizationMode(DependencyObject element)

Parameters

System.Windows.DependencyObject element

The object on which to query the value.

Returns

VirtualizationMode

The current virtualization mode.

LineDown()

Scroll content by one line to the bottom. Subclasses can override this method and call SetVerticalOffset to change the behavior of what "line" means.

Declaration

public virtual void LineDown()

LineLeft()

Scroll content by one line to the left. Subclasses can override this method and call SetHorizontalOffset to change the behavior of what "line" means.

Declaration

public virtual void LineLeft()

LineRight()

Scroll content by one line to the right. Subclasses can override this method and call SetHorizontalOffset to change the behavior of what "line" means.

Declaration

public virtual void LineRight()

LineUp()

Scroll content by one line to the top. Subclasses can override this method and call SetVerticalOffset to change the behavior of what "line" means.

Declaration

public virtual void LineUp()

MakeVisible(Visual, Rect)

GridViewVirtualizingPanel implementation of System.Windows.Controls.Primitives.IScrollInfo.MakeVisible(System.Windows.Media.Visual,System.Windows.Rect).

Declaration

public Rect MakeVisible(Visual visual, Rect rectangle)

Parameters

System.Windows.Media.Visual visual

System.Windows.Rect rectangle

Returns

System.Windows.Rect

Remarks

The goal is to change offsets to bring the child into view, and return a rectangle in our space to make visible. The rectangle we return is in the physical dimension the input target rect transformed into our pace. In the logical dimension, it is our immediate child's rect.

MeasureOverride(Size)

General GridViewVirtualizingPanel layout behavior is to grow unbounded in the "stacking" direction (Size To Content). Children in this dimension are encouraged to be as large as they like. In the other dimension, GridViewVirtualizingPanel will assume the maximum size of its children.

Declaration

protected override Size MeasureOverride(Size constraint)

Parameters

System.Windows.Size constraint

Constraint.

Returns

System.Windows.Size

Desired size.

Remarks

When scrolling, GridViewVirtualizingPanel will not grow in layout size but effectively add the children on a z-plane which will probably be clipped by some parent (typically a ScrollContentPresenter) to Stack's size.

MouseWheelDown()

Scroll content by one page to the bottom. Subclasses can override this method and call SetVerticalOffset to change the behavior of the mouse wheel increment.

Declaration

public virtual void MouseWheelDown()

MouseWheelLeft()

Scroll content by one page to the left. Subclasses can override this method and call SetHorizontalOffset to change the behavior of the mouse wheel increment.

Declaration

public virtual void MouseWheelLeft()

MouseWheelRight()

Scroll content by one page to the right. Subclasses can override this method and call SetHorizontalOffset to change the behavior of the mouse wheel increment.

Declaration

public virtual void MouseWheelRight()

MouseWheelUp()

Scroll content by one page to the top. Subclasses can override this method and call SetVerticalOffset to change the behavior of the mouse wheel increment.

Declaration

public virtual void MouseWheelUp()

OnCleanUpVirtualizedItem(CleanUpVirtualizedItemEventArgs)

Called when an item is being re-virtualized.

Declaration

protected virtual void OnCleanUpVirtualizedItem(CleanUpVirtualizedItemEventArgs e)

Parameters

CleanUpVirtualizedItemEventArgs e

OnClearChildren()

Called when the UI collection of children is cleared by the base Panel class.

Declaration

protected override void OnClearChildren()

OnGotKeyboardFocus(KeyboardFocusChangedEventArgs)

Override of OnGotKeyboardFocus. Called when focus moves to any child or sub child of this VSP Used by MyTreeView virtualization to keep track of the focused item.

Declaration

protected override void OnGotKeyboardFocus(KeyboardFocusChangedEventArgs e)

Parameters

System.Windows.Input.KeyboardFocusChangedEventArgs e

OnItemsChanged(Object, ItemsChangedEventArgs)

Called when the Items collection associated with the containing ItemsControl changes.

Declaration

protected override void OnItemsChanged(object sender, ItemsChangedEventArgs args)

Parameters

System.Object sender

Sender.

System.Windows.Controls.Primitives.ItemsChangedEventArgs args

Event arguments.

OnLostKeyboardFocus(KeyboardFocusChangedEventArgs)

Override of OnLostKeyboardFocus. Called when focus moves away from this VSP. Used by MyTreeView virtualization to keep track of the focused item.

Declaration

protected override void OnLostKeyboardFocus(KeyboardFocusChangedEventArgs e)

Parameters

System.Windows.Input.KeyboardFocusChangedEventArgs e

OnViewportSizeChanged(Size, Size)

Allows subclasses to be notified of changes to the viewport size data.

Declaration

protected virtual void OnViewportSizeChanged(Size oldViewportSize, Size newViewportSize)

Parameters

System.Windows.Size oldViewportSize

The old value of the size.

System.Windows.Size newViewportSize

The new value of the size.

PageDown()

Scroll content by one page to the bottom. Subclasses can override this method and call SetVerticalOffset to change the behavior of what "page" means.

Declaration

public virtual void PageDown()

PageLeft()

Scroll content by one page to the left. Subclasses can override this method and call SetHorizontalOffset to change the behavior of what "page" means.

Declaration

public virtual void PageLeft()

PageRight()

Scroll content by one page to the right. Subclasses can override this method and call SetHorizontalOffset to change the behavior of what "page" means.

Declaration

public virtual void PageRight()

PageUp()

Scroll content by one page to the top. Subclasses can override this method and call SetVerticalOffset to change the behavior of what "page" means.

Declaration

public virtual void PageUp()

RemoveCleanUpVirtualizedItemHandler(DependencyObject, CleanUpVirtualizedItemEventHandler)

Removes a handler for the CleanUpVirtualizedItem attached event.

Declaration

public static void RemoveCleanUpVirtualizedItemHandler(DependencyObject element, CleanUpVirtualizedItemEventHandler handler)

Parameters

System.Windows.DependencyObject element

DependencyObject that listens to this event.

CleanUpVirtualizedItemEventHandler handler

Event Handler to be removed.

SetHorizontalOffset(Double)

Set the HorizontalOffset to the passed value.

Declaration

public void SetHorizontalOffset(double offset)

Parameters

System.Double offset

SetIsVirtualizing(DependencyObject, Boolean)

Sets the value for IsVirtualizingProperty.

Declaration

public static void SetIsVirtualizing(DependencyObject element, bool value)

Parameters

System.Windows.DependencyObject element

The element on which to set the value.

System.Boolean value

True if virtualizing, false otherwise.

SetTreeVirtualizationMode(DependencyObject, VirtualizationMode)

Sets the value for TreeVirtualizationModeProperty.

Declaration

public static void SetTreeVirtualizationMode(DependencyObject element, VirtualizationMode value)

Parameters

System.Windows.DependencyObject element

The element on which to set the value.

VirtualizationMode value

The desired virtualization mode.

SetVerticalOffset(Double)

Set the VerticalOffset to the passed value.

Declaration

public void SetVerticalOffset(double offset)

Parameters

System.Double offset

SetVirtualizationMode(DependencyObject, VirtualizationMode)

Sets the value for VirtualizationModeProperty.

Declaration

public static void SetVirtualizationMode(DependencyObject element, VirtualizationMode value)

Parameters

System.Windows.DependencyObject element

The element on which to set the value.

VirtualizationMode value

The desired virtualization mode.

Extension Methods

CollectionExtensions.ToEnumerable<T>(T)

EnumerableExtensions.ToEnumerable<T>(T)