SetVScrollBarPosition Method (GdViewer)

In This Topic

Sets the required position of the vertical scrollbar, in pixels, related to the document currently displayed in the GdViewer control. In other words, the vertical scrollbar moves to the newly specified coordinate on the vertical axis. This coordinate relates to the actual document area of the currently displayed page.

The ScrollViewer event is raised if the scrollbar has moved.

Syntax

Visual Basic
C#
Delphi
JScript
Managed Extensions for C++
C++/CLI

'Declaration
 
Public Sub SetVScrollBarPosition( _
   ByVal NewPos As Integer _
)

public void SetVScrollBarPosition( 
   int NewPos
)

public procedure SetVScrollBarPosition( 
    NewPos: Integer
);

public function SetVScrollBarPosition( 
   NewPos : int
);

public: void SetVScrollBarPosition( 
   int NewPos
)

public:
void SetVScrollBarPosition( 
   int NewPos
)

Parameters

NewPos: The new vertical coordinate, in pixels, where the vertical scrollbar is to be moved. If this value is out of the expected range, the toolkit sets the current value to the nearest one, means minimum or maximum one.

Remarks

Please note that if the newly specified value is out of the expected range, the toolkit sets the current value to the nearest one (means minimum or maximum one) without reporting any error. Otherwise, you can regularly apply the GetStat method to determine if this method has been successful.

Just to remind you, that this coordinate is 0-based with the origin being in the top left corner in the document pages area and it is related to the current page determined by the CurrentPage property.

Be aware that the ScrollViewer event is raised only if the scrollbar has really moved.

Example

How to set the new position of the scrollbars.

VB.NET
C#

'We assume that the GdViewer1 control has been properly integrated.
If GdViewer1.DisplayFromFile("") = GdPictureStatus.OK Then
            
    'The current position of both scrollbars after displaying the document
    'according to your currently defined GdViewer control settings.
    Dim x As Integer = GdViewer1.GetHScrollBarPosition()
    Dim y As Integer = GdViewer1.GetVScrollBarPosition()
    MessageBox.Show("The scrollbars are set to this position: " + x + ", " + y, "GdViewer.SetVScrollBarPosition")
            
    If (x <> 0) OrElse (y <> 0) Then
        'Setting the scrollbars to the required position.
        GdViewer1.SetHScrollBarPosition(0)
        GdViewer1.SetVScrollBarPosition(0)
        MessageBox.Show("The scrollbars are now set to this position: 0, 0", "GdViewer.SetVScrollBarPosition")
    End If
            
    'Do your other stuff here.
    GdViewer1.CloseDocument()
Else
    MessageBox.Show("This file can't be displayed. Status: " + GdViewer1.GetStat().ToString(), "GdViewer.SetVScrollBarPosition")
End If

//We assume that the GdViewer1 control has been properly integrated.
if (GdViewer1.DisplayFromFile("") == GdPictureStatus.OK)
{
    //The current position of both scrollbars after displaying the document
    //according to your currently defined GdViewer control settings.
    int x = GdViewer1.GetHScrollBarPosition();
    int y = GdViewer1.GetVScrollBarPosition();
    MessageBox.Show("The scrollbars are set to this position: " + x + ", " + y, "GdViewer.SetVScrollBarPosition");
            
    if ((x != 0) || (y != 0))
    {
        //Setting the scrollbars to the required position.
        GdViewer1.SetHScrollBarPosition(0);
        GdViewer1.SetVScrollBarPosition(0);
        MessageBox.Show("The scrollbars are now set to this position: 0, 0", "GdViewer.SetVScrollBarPosition");
    }
            
    //Do your other stuff here.
    GdViewer1.CloseDocument();
}
else
{
    MessageBox.Show("This file can't be displayed. Status: " + GdViewer1.GetStat().ToString(), "GdViewer.SetVScrollBarPosition");
}

Reference

GdViewer Class
GdViewer Members
ScrollViewer Event
GetVScrollBarPosition Method
GetVScrollBarMaxPosition Method
SetHVScrollBarPosition Method
GetDisplayedArea Method
GetDocumentLeft Method
GetDocumentTop Method