WinForms ListView draws HELL SLOW in Windows 7 Compared to XP

Question

I'm using ListView in VirtualMode and Details View with small icons.

This ListView have like 100,000 items inside.

The problem is that drawing this listview is much slower in Windows 7 compared to XP.

You can fill the slow drawing while scrolling the ListView or while multi-selecting items.

Additionally, i noticed that drawing become slower with each column added.

RetrieveVirtualItem event handler for now doing nothing but return literal values, so this is not the bottleneck.

Any ideas?

UPDATE: Source code for reproduce:

FlickerFreeListView.cs:

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.ComponentModel;
using System.Drawing;
using System.Reflection;
using System.Diagnostics;

namespace ListViewTest
{
    public class FlickerFreeListView : ListView
    {
        public FlickerFreeListView()
        {
            base.SetStyle(ControlStyles.OptimizedDoubleBuffer | ControlStyles.AllPaintingInWmPaint, true);
        }
    }
}

Form1.cs:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Diagnostics;

namespace ListViewTest
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();

            _item = new ListViewItem(new string[6]);
        }

        private ListViewItem _item;

        private void listView1_RetrieveVirtualItem(object sender, RetrieveVirtualItemEventArgs e)
        {
            string itemIndexStr = e.ItemIndex.ToString();
            _item.Text = itemIndexStr;
            _item.SubItems[1].Text = "blablablablablablablablablablablablablablablablablablablablablablablablablablablablablablablablabla";
            _item.SubItems[2].Text = itemIndexStr;
            _item.SubItems[3].Text = itemIndexStr;
            _item.SubItems[4].Text = itemIndexStr;
            _item.SubItems[5].Text = itemIndexStr;
            e.Item = _item;
        }
    }
}

Form1.Designer.cs:

namespace ListViewTest
{
    partial class Form1
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.listView1 = new ListViewTest.FlickerFreeListView();
            this.columnHeader1 = new System.Windows.Forms.ColumnHeader();
            this.columnHeader2 = new System.Windows.Forms.ColumnHeader();
            this.columnHeader3 = new System.Windows.Forms.ColumnHeader();
            this.columnHeader4 = new System.Windows.Forms.ColumnHeader();
            this.columnHeader5 = new System.Windows.Forms.ColumnHeader();
            this.columnHeader6 = new System.Windows.Forms.ColumnHeader();
            this.SuspendLayout();
            // 
            // listView1
            // 
            this.listView1.AutoArrange = false;
            this.listView1.Columns.AddRange(new System.Windows.Forms.ColumnHeader[] {
        this.columnHeader1,
        this.columnHeader2,
        this.columnHeader3,
        this.columnHeader4,
        this.columnHeader5,
        this.columnHeader6});
            this.listView1.Dock = System.Windows.Forms.DockStyle.Fill;
            this.listView1.FullRowSelect = true;
            this.listView1.HideSelection = false;
            this.listView1.Location = new System.Drawing.Point(0, 0);
            this.listView1.Name = "listView1";
            this.listView1.Size = new System.Drawing.Size(1032, 388);
            this.listView1.TabIndex = 0;
            this.listView1.UseCompatibleStateImageBehavior = false;
            this.listView1.View = System.Windows.Forms.View.Details;
            this.listView1.VirtualListSize = 100000;
            this.listView1.VirtualMode = true;
            this.listView1.RetrieveVirtualItem += new System.Windows.Forms.RetrieveVirtualItemEventHandler(this.listView1_RetrieveVirtualItem);
            // 
            // columnHeader1
            // 
            this.columnHeader1.Width = 92;
            // 
            // columnHeader2
            // 
            this.columnHeader2.Width = 405;
            // 
            // Form1
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(1032, 388);
            this.Controls.Add(this.listView1);
            this.Name = "Form1";
            this.Text = "Form1";
            this.WindowState = System.Windows.Forms.FormWindowState.Maximized;
            this.ResumeLayout(false);

        }

        #endregion

        private FlickerFreeListView listView1;
        private System.Windows.Forms.ColumnHeader columnHeader1;
        private System.Windows.Forms.ColumnHeader columnHeader2;
        private System.Windows.Forms.ColumnHeader columnHeader3;
        private System.Windows.Forms.ColumnHeader columnHeader4;
        private System.Windows.Forms.ColumnHeader columnHeader5;
        private System.Windows.Forms.ColumnHeader columnHeader6;
    }
}

Answer 1

I do measure a slowdown on this code, XP draws the listview in about 47 msec, Win7 needs about 96 msec, roughly twice as slow. Not sure if that deserves the 'hell' moniker. I don't know what causes it but don't doubt that Aero has something to do with it. Turning it off isn't exactly a desirable option.

Luckily you made a mistake in your code, one that costs 48 msec in my measurements. Giving you back the exact perf you had on XP. You re-use the same ListViewItem, you're supposed to create a new one. Add this line of code to the RetrieveVirtualItem event handler:

    private void listView1_RetrieveVirtualItem(object sender, RetrieveVirtualItemEventArgs e)
    {
        var _item = new ListViewItem(new string[6]);
        // etc...
    }

And get rid of the field.

Answer 2

Try to change the SetStyle line to :

base.SetStyle(ControlStyles.UserPaint | ControlStyles.OptimizedDoubleBuffer | ControlStyles.AllPaintingInWmPaint, true); 

UserPaint -

"If true, the control paints itself rather than the operating system doing so" (MSDN)

.

Answer 3

Try to use WS_EX_COMPOSITED, it improves performance of virtual list quite a bit:

protected override CreateParams CreateParams
{
    get
    {
        CreateParams cp = base.CreateParams;
        cp.ExStyle |= 0x02000000;
        return cp;
    }
}

Edited: At least it reduces drawing artifacts.