Class RadScrollBarElement

Implements the basic functionality for scrolling.

Inheritance
System.Object
DisposableObject
RadObject
RadElement
VisualElement
RadComponentElement
RadItem
RadScrollBarElement
Inherited Members
System.Object.Equals(System.Object)
System.Object.Equals(System.Object, System.Object)
System.Object.ReferenceEquals(System.Object, System.Object)
System.Object.GetHashCode()
System.Object.GetType()
System.Object.MemberwiseClone()
Namespace: Telerik.WinControls.UI
Assembly: Telerik.WinControls.UI.dll

Syntax

[ComVisible(false)]
public class RadScrollBarElement : RadItem, INotifyPropertyChanged, ICustomTypeDescriptor, ISupportSystemSkin, IComponent, IDisposable, IBindableComponent, ISupportDrag, ISupportDrop, IShortcutProvider, IStylableElement, IStylableNode
Remarks

This class can be used both for horizontal and for vertical scrolling via its property ScrollType. In the Toolbox only the specialized children are put: RadHScrollBar and RadVScrollBar.

To adjust the value range of the scroll bar control, set the Minimum and Maximum properties. To adjust the distance the scroll thumb moves, set the SmallChange and LargeChange properties. To adjust the starting point of the scroll thumb, set the Value property when the control is initially displayed.

Constructors

RadScrollBarElement()

Declaration
public RadScrollBarElement()

Fields

DefaultScrollType

ScrollType
Declaration
public const ScrollType DefaultScrollType = ScrollType.Horizontal
Field Value
ScrollType

GradientAngleCorrectionProperty

Identifies the GradientAngleCorrection dependency property.

Declaration
public static readonly RadProperty GradientAngleCorrectionProperty
Field Value
RadProperty

HorizontalScrollBarHeight

Gets or sets the default height for horizontal scroll bars.

Declaration
public static int HorizontalScrollBarHeight
Field Value
System.Int32

IsMouseOverScrollBarProperty

Identifies the IsMouseOverScrollBar dependency property.

Declaration
public static readonly RadProperty IsMouseOverScrollBarProperty
Field Value
RadProperty

MinThumbLengthProperty

Identifies the MinThumbLength dependency property.

Declaration
public static readonly RadProperty MinThumbLengthProperty
Field Value
RadProperty

PressedProperty

Identifies the Pressed dependency property.

Declaration
public static readonly RadProperty PressedProperty
Field Value
RadProperty

ScrollTypeProperty

Identifies the ScrollType dependency property.

Declaration
public static readonly RadProperty ScrollTypeProperty
Field Value
RadProperty

ThumbLengthProportionProperty

Identifies the ThumbLengthProportion dependency property.

Declaration
public static readonly RadProperty ThumbLengthProportionProperty
Field Value
RadProperty

VerticalScrollBarWidth

Gets or sets the default width for vertical scroll bars.

Declaration
public static int VerticalScrollBarWidth
Field Value
System.Int32

Properties

BorderElement

Declaration
public BorderPrimitive BorderElement { get; }
Property Value
BorderPrimitive

ClampValue

Indicates whether invalid values should be clamped or an exception should be thrown

Declaration
public bool ClampValue { get; set; }
Property Value
System.Boolean

FillElement

Declaration
public FillPrimitive FillElement { get; }
Property Value
FillPrimitive

FirstButton

Gets the first button element of this scrollbar

Declaration
public ScrollBarButton FirstButton { get; }
Property Value
ScrollBarButton

GradientAngleCorrection

Controls the angle that the fill primitive will be rotated when switching from horizontal to vertical orientation

Declaration
[RadPropertyDefaultValue("GradientAngleCorrection", typeof(RadScrollBarElement))]
public float GradientAngleCorrection { get; set; }
Property Value
System.Single

LargeChange

Gets or sets a value to be added to or subtracted from the Value property when the scroll thumb is moved a large distance.

Declaration
public int LargeChange { get; set; }
Property Value
System.Int32

A numeric value. The default value is 10.
Remarks

When the user presses the PAGE UP or PAGE DOWN key, clicks in the scroll bar track on either side of the scroll thumb, or calls one of the PageXXX() functions, the Value property changes according to the value set in the LargeChange property.

Maximum

Gets or sets the upper limit of the scrollable range.

Declaration
public int Maximum { get; set; }
Property Value
System.Int32

A numeric value. The default value is 100.
Remarks

NOTE: The value of a scroll bar cannot reach its maximum value through user interaction at run time. The maximum value that can be reached is equal to the Maximum property value minus the LargeChange property value plus 1. The maximum value can only be reached programmatically.

Minimum

Gets or sets the lower limit for the values of the scrollable range.

Declaration
public int Minimum { get; set; }
Property Value
System.Int32

A numeric value. The default value is 0.

MinThumbLength

Gets or sets the minimum length of the scrolling thumb. See ThumbLength for more information about thumb length.

Declaration
[RadPropertyDefaultValue("MinThumbLength", typeof(RadScrollBarElement))]
public int MinThumbLength { get; set; }
Property Value
System.Int32

An integer value that gives the minimum thumb length. It is taken into account no matter if the thumb length is calculated automatically or the thumb length is set explicitly. The thumb length could be smaller than MinThumbLength if there is no space in the scroll bar.

ScrollTimerDelay

Gets or sets the scroll timer delay

Declaration
public int ScrollTimerDelay { get; set; }
Property Value
System.Int32

ScrollType

Gets or sets the ScrollType - it could be horizontal or vertical.

Declaration
[RadPropertyDefaultValue("ScrollType", typeof(RadScrollBarElement))]
public ScrollType ScrollType { get; set; }
Property Value
ScrollType

SecondButton

Gets the second button element of this scrollbar

Declaration
public ScrollBarButton SecondButton { get; }
Property Value
ScrollBarButton

SmallChange

Gets or sets the value to be added to or subtracted from the Value property when the scroll thumb is moved a small distance.

Declaration
public int SmallChange { get; set; }
Property Value
System.Int32

A numeric value. The default value is 1.
Remarks

When the user presses one of the arrow keys, clicks one of the scroll bar buttons or calls one of the LineXXX() functions, the Value property changes according to the value set in the SmallChange property.

ThumbElement

Gets the thumb element of this scrollbar

Declaration
public ScrollBarThumb ThumbElement { get; }
Property Value
ScrollBarThumb

ThumbLength

Gets the length of the scrolling thumb. Thumb length is the thumb's height for vertical scroll bar and the thumb's width for horizontal scroll bar.

Declaration
public int ThumbLength { get; }
Property Value
System.Int32

ThumbLengthProportion

Gets or sets a value between 0.0 and 1.0 that indicates what part of the scrollable area can be occupied by the thumb. If the value is 0.0 then the thumb should be with length 0 but the property MinThumbLength will cause the thumb to be larger. If the value is 1.0 the thumb takes the whole area between the two scrolling buttons. Negative value means that the thumb length should be calculated automatically based on Minimum, Maximum and LargeChange values.

Declaration
[RadPropertyDefaultValue("ThumbLengthProportion", typeof(RadScrollBarElement))]
public double ThumbLengthProportion { get; set; }
Property Value
System.Double

Value

Gets or sets a numeric value that represents the current position of the scroll thumb on the scroll bar.

Declaration
public int Value { get; set; }
Property Value
System.Int32

A numeric value that is within the Minimum and Maximum range. The default value is 0.

Methods

ArrangeOverride(SizeF)

Declaration
protected override SizeF ArrangeOverride(SizeF finalSize)
Parameters
System.Drawing.SizeF finalSize

Returns
System.Drawing.SizeF

Overrides

CreateChildElements()

Declaration
protected override void CreateChildElements()
Overrides

DisposeManagedResources()

Declaration
protected override void DisposeManagedResources()
Overrides

GetParameters()

Retrieves the srolling parameters.

Declaration
public ScrollBarParameters GetParameters()
Returns
ScrollBarParameters

See Also

GetVistaVisualStyle()

Gets the Vista visual style element for this scroll bar.

Declaration
public override VisualStyleElement GetVistaVisualStyle()
Returns
System.Windows.Forms.VisualStyles.VisualStyleElement

The Vista visual style element.
Overrides

GetXPVisualStyle()

Gets the XP visual style element for this scroll bar.

Declaration
public override VisualStyleElement GetXPVisualStyle()
Returns
System.Windows.Forms.VisualStyles.VisualStyleElement

The XP visual style element.
Overrides

InitializeFields()

Declaration
protected override void InitializeFields()
Overrides

InitializeSystemSkinPaint()

Declaration
protected override void InitializeSystemSkinPaint()
Overrides

MeasureOverride(SizeF)

Declaration
protected override SizeF MeasureOverride(SizeF availableSize)
Parameters
System.Drawing.SizeF availableSize

Returns
System.Drawing.SizeF

Overrides

OnLoaded()

Declaration
protected override void OnLoaded()
Overrides

OnMouseDown(MouseEventArgs)

Declaration
protected override void OnMouseDown(MouseEventArgs e)
Parameters
System.Windows.Forms.MouseEventArgs e

Overrides

OnMouseLeave(EventArgs)

Declaration
protected override void OnMouseLeave(EventArgs e)
Parameters
System.EventArgs e

Overrides

OnMouseUp(MouseEventArgs)

Declaration
protected override void OnMouseUp(MouseEventArgs e)
Parameters
System.Windows.Forms.MouseEventArgs e

Overrides

OnPanGesture(PanGestureEventArgs)

Declaration
protected override void OnPanGesture(PanGestureEventArgs args)
Parameters
PanGestureEventArgs args

Overrides

OnPropertyChanged(RadPropertyChangedEventArgs)

Declaration
protected override void OnPropertyChanged(RadPropertyChangedEventArgs e)
Parameters
RadPropertyChangedEventArgs e

Overrides

OnScroll(ScrollEventArgs)

Declaration
protected virtual void OnScroll(ScrollEventArgs args)
Parameters
System.Windows.Forms.ScrollEventArgs args

OnScrollParameterChanged()

Declaration
protected virtual void OnScrollParameterChanged()

OnValueChanged()

Declaration
protected virtual void OnValueChanged()

OnValueChanged(Int32, Int32)

Declaration
protected virtual void OnValueChanged(int oldValue, int newValue)
Parameters
System.Int32 oldValue

System.Int32 newValue

PaintElementSkin(IGraphics)

Declaration
protected override void PaintElementSkin(IGraphics graphics)
Parameters
IGraphics graphics

Overrides

PaintHorizontalVisualStylesElements()

Declaration
protected virtual void PaintHorizontalVisualStylesElements()

PaintVerticalVisualStyleElements()

Declaration
protected virtual void PaintVerticalVisualStyleElements()

PaintVisualStyleElement(Graphics, VisualStyleElement, Rectangle)

Declaration
protected virtual void PaintVisualStyleElement(Graphics graphics, VisualStyleElement element, Rectangle bounds)
Parameters
System.Drawing.Graphics graphics

System.Windows.Forms.VisualStyles.VisualStyleElement element

System.Drawing.Rectangle bounds

PerformFirst()

Simulate scrolling with positioning the thumb on its first position. Unlike setting property Value this function fires scrolling events.

Declaration
public void PerformFirst()

PerformLargeDecrement(Int32)

Simulate scrolling - just like the top / left area according the thumb is pressed. Unlike setting property Value this function fires scrolling events.

Declaration
public void PerformLargeDecrement(int numSteps)
Parameters
System.Int32 numSteps

Value is decremented with (numSteps * LargeChange)

PerformLargeIncrement(Int32)

Simulate scrolling - just like the bottom / right area according the thumb is pressed. Unlike setting property Value this function fires scrolling events.

Declaration
public void PerformLargeIncrement(int numSteps)
Parameters
System.Int32 numSteps

Value is incremented with (numSteps * LargeChange)

PerformLast()

Simulate scrolling with positioning the thumb on its last position. Unlike setting property Value this function fires scrolling events.

Declaration
public void PerformLast()

PerformScrollTo(Point)

Scrolls just like the thumb is dragged at given position

Declaration
public void PerformScrollTo(Point position)
Parameters
System.Drawing.Point position

Position of the thumb (in screen coordinates).

PerformSmallDecrement(Int32)

Simulate scrolling - just like the top / left button is pressed. Unlike setting property Value this function fires scrolling events.

Declaration
public void PerformSmallDecrement(int numSteps)
Parameters
System.Int32 numSteps

Value is decremented with (numSteps * SmallChange)

PerformSmallIncrement(Int32)

Simulate scrolling - just like the bottom / right button is pressed. Unlike setting property Value this function fires scrolling events.

Declaration
public void PerformSmallIncrement(int numSteps)
Parameters
System.Int32 numSteps

Value is incremented with (numSteps * SmallChange)

SetParameters(ScrollBarParameters)

Sets the given scroll parameters.

Declaration
public void SetParameters(ScrollBarParameters parameters)
Parameters
ScrollBarParameters parameters

See Also

ShouldPaintChild(RadElement)

Declaration
protected override bool ShouldPaintChild(RadElement element)
Parameters
RadElement element

Returns
System.Boolean

Overrides

UnitializeSystemSkinPaint()

Declaration
protected override void UnitializeSystemSkinPaint()
Overrides

Events

Scroll

Occurs when the scroll thumb has been moved by either a mouse or keyboard action.

Declaration
public event ScrollEventHandler Scroll
Event Type
System.Windows.Forms.ScrollEventHandler

ScrollParameterChanged

Occurs when a property that affects the scrolling is changed. See ScrollBarParameters for more information on which properties affect the scrolling.

Declaration
public event EventHandler ScrollParameterChanged
Event Type
System.EventHandler

ValueChanged

Occurs when the Value property is changed, either by a Scroll event or programmatically.

Declaration
public event EventHandler ValueChanged
Event Type
System.EventHandler

Extension Methods