Question

All I want is to update an ListViewItem’s text whithout seeing any flickering.

This is my code for updating (called several times):

listView.BeginUpdate(); listViewItem.SubItems[0].Text = state.ToString();    // update the state listViewItem.SubItems[1].Text = progress.ToString(); // update the progress listView.EndUpdate(); 

I’ve seen some solutions that involve overriding the component’s WndProc():

protected override void WndProc(ref Message m) {     if (m.Msg == (int)WM.WM_ERASEBKGND)     {         m.Msg = (int)IntPtr.Zero;     }     base.WndProc(ref m); } 

They say it solves the problem, but in my case It didn’t. I believe this is because I’m using icons on every item.

Answer 1

To end this question, here is a helper class that should be called when the form is loading for each ListView or any other ListView’s derived control in your form. Thanks to ‘Brian Gillespie’ for giving the solution.

public enum ListViewExtendedStyles {     /// <summary>     /// LVS_EX_GRIDLINES     /// </summary>     GridLines = 0x00000001,     /// <summary>     /// LVS_EX_SUBITEMIMAGES     /// </summary>     SubItemImages = 0x00000002,     /// <summary>     /// LVS_EX_CHECKBOXES     /// </summary>     CheckBoxes = 0x00000004,     /// <summary>     /// LVS_EX_TRACKSELECT     /// </summary>     TrackSelect = 0x00000008,     /// <summary>     /// LVS_EX_HEADERDRAGDROP     /// </summary>     HeaderDragDrop = 0x00000010,     /// <summary>     /// LVS_EX_FULLROWSELECT     /// </summary>     FullRowSelect = 0x00000020,     /// <summary>     /// LVS_EX_ONECLICKACTIVATE     /// </summary>     OneClickActivate = 0x00000040,     /// <summary>     /// LVS_EX_TWOCLICKACTIVATE     /// </summary>     TwoClickActivate = 0x00000080,     /// <summary>     /// LVS_EX_FLATSB     /// </summary>     FlatsB = 0x00000100,     /// <summary>     /// LVS_EX_REGIONAL     /// </summary>     Regional = 0x00000200,     /// <summary>     /// LVS_EX_INFOTIP     /// </summary>     InfoTip = 0x00000400,     /// <summary>     /// LVS_EX_UNDERLINEHOT     /// </summary>     UnderlineHot = 0x00000800,     /// <summary>     /// LVS_EX_UNDERLINECOLD     /// </summary>     UnderlineCold = 0x00001000,     /// <summary>     /// LVS_EX_MULTIWORKAREAS     /// </summary>     MultilWorkAreas = 0x00002000,     /// <summary>     /// LVS_EX_LABELTIP     /// </summary>     LabelTip = 0x00004000,     /// <summary>     /// LVS_EX_BORDERSELECT     /// </summary>     BorderSelect = 0x00008000,     /// <summary>     /// LVS_EX_DOUBLEBUFFER     /// </summary>     DoubleBuffer = 0x00010000,     /// <summary>     /// LVS_EX_HIDELABELS     /// </summary>     HideLabels = 0x00020000,     /// <summary>     /// LVS_EX_SINGLEROW     /// </summary>     SingleRow = 0x00040000,     /// <summary>     /// LVS_EX_SNAPTOGRID     /// </summary>     SnapToGrid = 0x00080000,     /// <summary>     /// LVS_EX_SIMPLESELECT     /// </summary>     SimpleSelect = 0x00100000 }  public enum ListViewMessages {     First = 0x1000,     SetExtendedStyle = (First + 54),     GetExtendedStyle = (First + 55), }  /// <summary> /// Contains helper methods to change extended styles on ListView, including enabling double buffering. /// Based on Giovanni Montrone's article on <see cref='http://www.codeproject.com/KB/list/listviewxp.aspx'/> /// </summary> public class ListViewHelper {     private ListViewHelper()     {     }      [DllImport('user32.dll', CharSet = CharSet.Auto)]     private static extern int SendMessage(IntPtr handle, int messg, int wparam, int lparam);      public static void SetExtendedStyle(Control control, ListViewExtendedStyles exStyle)     {         ListViewExtendedStyles styles;         styles = (ListViewExtendedStyles)SendMessage(control.Handle, (int)ListViewMessages.GetExtendedStyle, 0, 0);         styles |= exStyle;         SendMessage(control.Handle, (int)ListViewMessages.SetExtendedStyle, 0, (int)styles);     }      public static void EnableDoubleBuffer(Control control)     {         ListViewExtendedStyles styles;         // read current style         styles = (ListViewExtendedStyles)SendMessage(control.Handle, (int)ListViewMessages.GetExtendedStyle, 0, 0);         // enable double buffer and border select         styles |= ListViewExtendedStyles.DoubleBuffer | ListViewExtendedStyles.BorderSelect;         // write new style         SendMessage(control.Handle, (int)ListViewMessages.SetExtendedStyle, 0, (int)styles);     }     public static void DisableDoubleBuffer(Control control)     {         ListViewExtendedStyles styles;         // read current style         styles = (ListViewExtendedStyles)SendMessage(control.Handle, (int)ListViewMessages.GetExtendedStyle, 0, 0);         // disable double buffer and border select         styles -= styles & ListViewExtendedStyles.DoubleBuffer;         styles -= styles & ListViewExtendedStyles.BorderSelect;         // write new style         SendMessage(control.Handle, (int)ListViewMessages.SetExtendedStyle, 0, (int)styles);     } }