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EnsureVisible Method
See Also 
Leadtools.WinForms Namespace > RasterImageList Class : EnsureVisible Method



index
The zero-based index of the item to scroll into view.
index
The zero-based index of the item to scroll into view.
Ensures that the specified item is visible within the control, scrolling the contents of the control if necessary.

Syntax

Visual Basic (Declaration) 
Public Sub EnsureVisible( _
   ByVal index As Integer _
)
Visual Basic (Usage)Copy Code
Dim instance As RasterImageList
Dim index As Integer
 
instance.EnsureVisible(index)
C# 
public void EnsureVisible( 
   int index
)
C++/CLI 
public:
void EnsureVisible( 
   int index
)

Parameters

index
The zero-based index of the item to scroll into view.

Example

This example will add a new item to the end of a RasterImageList control and make sure the item is visible to the user.

Visual BasicCopy Code
Public Sub RasterImageList_EnsureVisible(ByVal imageList As RasterImageList)
      Dim codecs As RasterCodecs = New RasterCodecs()
      Dim image As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "image1.cmp"))
      imageList.ScrollStyle = RasterImageListScrollStyle.Horizontal

      ' Append the new item to the image list control
      Dim item As RasterImageListItem = New RasterImageListItem(image, 1, "New Item")
      imageList.Items.Add(item)
      Dim nIndex As Integer = imageList.Items.IndexOf(item)

      ' Make sure this new item is visible to the user
      imageList.EnsureVisible(nIndex)
   End Sub

Public NotInheritable Class LEAD_VARS
   Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class
C#Copy Code
public void RasterImageList_EnsureVisible(RasterImageList imageList)
   {
      RasterCodecs codecs = new RasterCodecs();
      RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "image1.cmp"));
      imageList.ScrollStyle = RasterImageListScrollStyle.Horizontal;

      // Append the new item to the image list control
      RasterImageListItem item = new RasterImageListItem(image, 1, "New Item");
      imageList.Items.Add(item);
      int nIndex = imageList.Items.IndexOf(item);

      // Make sure this new item is visible to the user
      imageList.EnsureVisible(nIndex);
   }

static class LEAD_VARS
{
   public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
}

Remarks

You can use this method to ensure that a specific item is visible within the RasterImageList control. When performing validation on the items in a RasterImageList, you can call the EnsureVisible method to ensure that an item that failed validation is displayed in the RasterImageList control to allow the user to perform changes on the item. If the item that you want to ensure is visible is located above the viewable region of the RasterImageList control, calling the EnsureVisible method will scroll the contents of the control until it is the first item in the viewable area of the control. If the item is below the viewable region of the RasterImageList control, calling the EnsureVisible method will scroll the contents of the RasterImageList control until the item is the last item in the viewable area of the control.

To determine if an item is located at the top of the display area of a RasterImageList control, use the TopIndex property.

Requirements

Target Platforms: Microsoft .NET Framework 2.0, Windows 2000, Windows XP, Windows Server 2003 family, Windows Server 2008 family, Windows Vista, Windows 7

See Also