HorizontalExtent Property, SftTreeItems Object


	SftTreeItems.HorizontalExtent Property	Softel vdm, Inc.

Defines the current horizontal scrolling extent.

Syntax

Get
	VB.NET	Extent = object.HorizontalExtent As Single
	VB	Extent = object.HorizontalExtent As Single
	C#.NET	float Extent = object.HorizontalExtent;
	VC++	float Extent = object->HorizontalExtent; float Extent = object->GetHorizontalExtent();
	C	HRESULT object->get_HorizontalExtent(float* Extent);
	Delphi	Extent := object.HorizontalExtent : Single;
Put
	VB.NET	object.HorizontalExtent = Extent As Single
	VB	object.HorizontalExtent = Extent As Single
	C#.NET	float object.HorizontalExtent = Extent;
	VC++	float object->HorizontalExtent = Extent; void object->PutHorizontalExtent(float Extent);
	C	HRESULT object->put_HorizontalExtent(float Extent);
	Delphi	object.HorizontalExtent := Extent : Single;

object

A SftTreeItems object.

Extent

Defines the current horizontal scrolling extent. If this value is 0 (or less than the width of the tree control), horizontal scrolling is disabled. The units used depend on the container (Visual Basic, Visual C++, etc.) and the coordinate system used.

Comments

The HorizontalExtent property defines the current horizontal scrolling extent.

The Items.HorizontalExtent and Items.HorizontalExtentPix methods are synonyms, but may use different coordinate systems.

A tree control's displayable area can be wider than the tree control's window width. If the displayable area is wider, the tree control can be scrolled horizontally if it has a horizontal scroll bar (see Scrollbars property). The width of the displayable area can be set by the application using the Items.RecalcHorizontalExtent method or the Items.HorizontalExtent property. For performance reasons, the optimal width is not automatically calculated when adding items to a tree control.

The width Extent set using this property must be equal to or greater than the combined column widths plus the width returned by the ColumnsObj.OverheadWidth property.

The HorizontalExtent property defines the horizontal extent of the displayable area (or the left pane of a split tree control).

The Items.HorizontalExtent2 property defines the horizontal extent of the displayable area in the right pane of a split tree control. The Items.HorizontalExtent2 property can only be used with a split tree control.

If the width set is smaller than the actual window width, the control cannot be scrolled horizontally. The horizontal scroll bar will be disabled or hidden, based on the Scrollbars property.

By default, a tree control does not handle horizontal scrolling, even if the Scrollbars property defines scroll bars to be available. To start horizontal scrolling, an application has to use the Items.RecalcHorizontalExtent method or the Items.HorizontalExtent property. They indicate to the tree control that horizontal scrolling support is desired and allows it to determine the horizontal scrolling extent.

The tree control doesn't automatically update the horizontal extent when items are added or deleted or other methods or properties are used, which may invalidate the horizontal extent. The Items.RecalcHorizontalExtent method or Items.HorizontalExtent property have to be used again to recalculate or redefine the extent.