add images to virtual list

[Anushya]

Hi
I am trying to add image items to listview. Here how to handle if i
need to add images?? Pls go thru the code.

In the form where i have used this virtualListView, have handled
QueryItemText.. And text alone is working fine..

using System;
using System.Windows.Forms;
using System.Diagnostics;

namespace Microsoft.Samples.VirtualListView
{
#region VirtualListView Delegates
public delegate void QueryItemTextHandler(int item, int subItem,
out string text);
public delegate void QueryItemImageHandler(int item, int subItem,
out int imageIndex);
public delegate void QueryItemIndentHandler(int item, out int
itemIndent);
#endregion

/// <summary>
/// Summary description for VirtualListViewControl.
/// </summary>
public class VirtualListView : ListView {
// store the item count to prevent the call to
SendMessage(LVM_GETITEMCOUNT)
private int itemCount = 0;
public int ItemCount {
get { return itemCount; }
set {
itemCount = value;
int result;
result = WindowsFunction.SendMessage(
this.Handle,
(int)ListViewMessages.LVM_SETITEMCOUNT,
itemCount,
0);
}
}

public VirtualListView ()
{
// virtual listviews must be Details or List view with no
sorting
View = View.Details;
Sorting = SortOrder.None;
}

protected override System.Windows.Forms.CreateParams
CreateParams {
get {
CreateParams cp = base.CreateParams;
// LVS_OWNERDATA style must be set when the control is
created
cp.Style |= (int)ListViewStyles.LVS_OWNERDATA;
return cp;
}
}

public new System.Windows.Forms.View View {
get {
return new System.Windows.Forms.View();
}
set {
if (value == View.LargeIcon ||
value == View.SmallIcon) {
throw new ArgumentException("Icon views are
invalid for virtual ListViews", "View");
}
base.View = value;
}
}

#region Display query callbacks
public event QueryItemTextHandler QueryItemText;
public event QueryItemImageHandler QueryItemImage;
public event QueryItemIndentHandler QueryItemIndent;
#endregion

void OnDispInfoNotice(ref Message m, bool useAnsi) {

LVDISPINFO info =
(LVDISPINFO)m.GetLParam(typeof(LVDISPINFO));
string lvtext = null;

if((info.item.mask & (uint)ListViewItemMask.LVIF_TEXT) >
0) {
if (QueryItemText != null) {
QueryItemText(info.item.iItem, info.item.iSubItem,
out lvtext);
if (lvtext != null) {
try {
int maxIndex = Math.Min(info.item.cchTextMax-1, lvtext.Length);
char[] data = new char[maxIndex+1];
lvtext.CopyTo(0, data, 0, lvtext.Length);
data[maxIndex] = '\0';
System.Runtime.InteropServices.Marshal.Copy(data, 0,
info.item.pszText, data.Length);
}
catch (Exception e) {
Debug.WriteLine("Failed to copy text name
from client: " + e.ToString(), "VirtualListView.OnDispInfoNotice");
}
}
}
}

if((info.item.mask & (uint)ListViewItemMask.LVIF_IMAGE) >
0) {
int imageIndex = 0;
if (QueryItemImage != null) {
QueryItemImage(info.item.iItem,
info.item.iSubItem, out imageIndex);
}
info.item.iImage = imageIndex;
}

if ((info.item.mask & (uint)ListViewItemMask.LVIF_INDENT)

0) {

int itemIndent = 0;
if (QueryItemIndent != null) {
QueryItemIndent(info.item.iItem, out itemIndent);
}
info.item.iIndent = itemIndent;
}
m.Result = new IntPtr(0);
}
protected override void WndProc(ref
System.Windows.Forms.Message m) {
NMHDR nm1;
bool messageProcessed = false;
switch (m.Msg) {
case (int)WindowsMessage.WM_REFLECT +
(int)WindowsMessage.WM_NOTIFY:
nm1 = (NMHDR) m.GetLParam(typeof(NMHDR));
switch(nm1.code) {
case (int)ListViewNotices.LVN_GETDISPINFOW:
OnDispInfoNotice(ref m, false);
messageProcessed = true;
break;
default:
break;
}
break;
default:
break;
}
if (!messageProcessed) {
base.WndProc(ref m);
}
}
}
}