property Items.FirstVisibleItem as HITEM

Retrieves the handle of the first visible item into control.

 TypeDescription 
   HITEM A long expression that indicates the handle of the first visible item.  

Use the FirstVisibleItem, NextVisibleItem and IsItemVisible properties to get the items that fit the client area. Use the NextVisibleItem property to get the next visible item. Use the IsVisibleItem property to check whether an item fits the control's client area.

The following VB sample enumerates the items that fit the control's client area:

On Error Resume Next
Dim h As HITEM
Dim i As Long, j As Long, nCols As Long
nCols = G2antt1.Columns.Count
With G2antt1.Items
    h = .FirstVisibleItem
    While Not (h = 0) And .IsItemVisible(h)
        Dim s As String
        s = ""
        For j = 0 To nCols - 1
            s = s + .CellValue(h, j) + Chr(9)
        Next
        Debug.Print s
        h = .NextVisibleItem(h)
    Wend
End With

The FormatColumn event is fired before displaying a cell, so you can handle the FormatColumn to display anything on the cell at runtime. This way you can display the row position, you can display the value using the currency format, and so on. The FireFormatColumn property allows the control to fire the FormatColumn event for the column. The Position property specifies the position of the column.

The following VB sample handles the FormatColumn event to display the row position:

Private Sub G2antt1_FormatColumn(ByVal Item As EXG2ANTTLibCtl.HITEM, ByVal ColIndex As Long, Value As Variant)
    Value = G2antt1.Items.ItemPosition(Item)
End Sub 
Private Sub G2antt1_FormatColumn(ByVal Item As EXG2ANTTLibCtl.HITEM, ByVal ColIndex As Long, Value As Variant)
    Value = G2antt1.ScrollPos(True) + RelPos(Item)
End Sub

Private Function RelPos(ByVal hVisible As Long) As Long
    With G2antt1.Items
        Dim h As Long, i As Long, n As Long
        i = 0
        n = .VisibleCount + 1
        h = .FirstVisibleItem
        While (i <= n) And h <> 0 And h <> hVisible
            i = i + 1
            h = .NextVisibleItem(h)
        Wend
        RelPos = i
    End With
End Function

The following C++ sample enumerates the items that fit the control's client area:

#include "Items.h"
CItems items = m_g2antt.GetItems();
long hItem = items.GetFirstVisibleItem();
while ( hItem && items.GetIsItemVisible( hItem ) )
{
	OutputDebugString( V2S( &items.GetCellValue( COleVariant( hItem ), COleVariant( long(0) ) ) ) );
	hItem = items.GetNextVisibleItem( hItem );
}

The following VB.NET sample enumerates the items that fit the control's client area:

With AxG2antt1.Items
    Dim hItem As Integer
    hItem = .FirstVisibleItem
    While Not (hItem = 0)
        If (.IsItemVisible(hItem)) Then
            Debug.Print(.CellValue(hItem, 0))
            hItem = .NextVisibleItem(hItem)
        Else
            Exit While
        End If
    End While
End With

The following C# sample enumerates the items that fit the control's client area:

EXG2ANTTLib.Items items = axG2antt1.Items;
int hItem = items.FirstVisibleItem;
while ( ( hItem != 0 ) && (items.get_IsItemVisible(hItem)) )
{
	object strCaption = items.get_CellValue(hItem, 0);
	System.Diagnostics.Debug.WriteLine( strCaption != null ? strCaption.ToString() : "" );
	hItem = items.get_NextVisibleItem(hItem);
}

The following VFP sample enumerates the items that fit the control's client area:

with thisform.G2antt1.Items
	.DefaultItem = .FirstVisibleItem
	do while ( ( .DefaultItem <> 0 ) and ( .IsItemVisible( 0 ) ) )
		wait window .CellValue( 0, 0 )
		.DefaultItem = .NextVisibleItem( 0 )	
	enddo
endwith

 


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