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DrawListViewItemEventArgs Class

Note: This class is new in the .NET Framework version 2.0.

Provides data for the ListView.DrawItem event.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in system.windows.forms.dll)

public class DrawListViewItemEventArgs : EventArgs
public class DrawListViewItemEventArgs extends EventArgs
public class DrawListViewItemEventArgs extends EventArgs

The ListView.DrawItem event enables you to customize the appearance of a ListView control using owner drawing.

The ListView.DrawItem event is raised by a ListView control when the ListView.OwnerDraw property is set to true. The DrawListViewItemEventArgs passed to the event handler contains information about the ListViewItem to draw and also provides methods to help you draw the item.

Use the State or Item properties to retrieve information about the item to draw. Use the DrawListViewItemEventArgs.ItemIndex property to retrieve the index of the item.

Use the Graphics property to do the actual drawing within the area specified by the Bounds property. To draw standard ListView elements that do not need customization, use the DrawBackground, DrawText, and DrawFocusRectangle methods.

NoteNote

To avoid issues with graphics flickering when owner drawing, override the ListView control and set the DoubleBuffered property to true. This feature is available only on Windows XP and the Windows Server 2003 family when your application calls the Application.EnableVisualStyles method.

The following code example demonstrates how to provide custom drawing for a ListView control. The ListView control in the example has a gradient background. Subitems with negative values have a red foreground and a black background.

A handler for the ListView.DrawItem event draws the background for entire items. A handler for the ListView.DrawSubItem event draws the text values and both the text and background for subitems that have negative values. A handler for the DrawColumnHeader event draws each column header.

A ContextMenu component provides a way to switch between the details view and the list view. In the list view, only the ListView.DrawItem event is fired. In this case, the text and background are both drawn in the ListView.DrawItem event handler.

using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Globalization;
using System.Windows.Forms;

public class ListViewOwnerDraw : Form
{
    private ListView listView1 = new ListView();
    private ContextMenu contextMenu1 = new ContextMenu();

    public ListViewOwnerDraw()
    {
        // Initialize the ListView control.
        listView1.BackColor = Color.Black;
        listView1.ForeColor = Color.White;
        listView1.Dock = DockStyle.Fill;
        listView1.View = View.Details;
        listView1.FullRowSelect = true;

        // Add columns to the ListView control.
        listView1.Columns.Add("Name", 72, HorizontalAlignment.Center);
        listView1.Columns.Add("First", 72, HorizontalAlignment.Center);
        listView1.Columns.Add("Second", 72, HorizontalAlignment.Center);
        listView1.Columns.Add("Third", 72, HorizontalAlignment.Center);

        // Create items and add them to the ListView control.
        ListViewItem listViewItem1 = new ListViewItem(new string[] { "One", "20", "30", "-40" }, -1);
        ListViewItem listViewItem2 = new ListViewItem(new string[] { "Two", "-250", "145", "37" }, -1);
        ListViewItem listViewItem3 = new ListViewItem(new string[] { "Three", "200", "800", "-1,001" }, -1);
        ListViewItem listViewItem4 = new ListViewItem(new string[] { "Four", "not available", "-2", "100" }, -1);
        listView1.Items.AddRange(new ListViewItem[] { listViewItem1, listViewItem2, listViewItem3, listViewItem4 });

        // Initialize the shortcut menu and 
        // assign it to the ListView control.
        contextMenu1.MenuItems.Add("List",
            new EventHandler(menuItemList_Click));
        contextMenu1.MenuItems.Add("Details",
            new EventHandler(menuItemDetails_Click));
        listView1.ContextMenu = contextMenu1;

        // Configure the ListView control for owner-draw and add 
        // handlers for the owner-draw events.
        listView1.OwnerDraw = true;
        listView1.DrawItem += new
            DrawListViewItemEventHandler(listView1_DrawItem);
        listView1.DrawSubItem += new
            DrawListViewSubItemEventHandler(listView1_DrawSubItem);
        listView1.DrawColumnHeader += new
            DrawListViewColumnHeaderEventHandler(listView1_DrawColumnHeader);

        // Add a handler for the MouseMove event to compensate for an 
        // extra DrawItem event that occurs the first time the mouse 
        // moves over each row. 
        listView1.MouseMove += new MouseEventHandler(listView1_MouseMove);

        // Add a handler for the MouseUp event so an item can be 
        // selected by clicking anywhere along its width.
        listView1.MouseUp += new MouseEventHandler(listView1_MouseUp);

        // Initialize the form and add the ListView control to it.
        this.ClientSize = new Size(292, 79);
        this.FormBorderStyle = FormBorderStyle.FixedSingle;
        this.MaximizeBox = false;
        this.Text = "ListView OwnerDraw Example";
        this.Controls.Add(listView1);
    }

    // Clean up any resources being used.        
    protected override void Dispose(bool disposing)
    {
        if (disposing)
        {
            contextMenu1.Dispose();
        }
        base.Dispose(disposing);
    }

    [STAThread]
    static void Main()
    {
        Application.EnableVisualStyles();
        Application.Run(new ListViewOwnerDraw());
    }

    // Sets the ListView control to the List view.
    private void menuItemList_Click(object sender, EventArgs e)
    {
        listView1.View = View.List;
        listView1.Invalidate();
    }

    // Sets the ListView control to the Details view.
    private void menuItemDetails_Click(object sender, EventArgs e)
    {
        listView1.View = View.Details;

        // Reset the tag on each item to re-enable the workaround in
        // the MouseMove event handler.
        foreach (ListViewItem item in listView1.Items)
        {
            item.Tag = null;
        }
    }

    // Selects and focuses an item when it is clicked anywhere along 
    // its width. The click must normally be on the parent item text.
    private void listView1_MouseUp(object sender, MouseEventArgs e)
    {
        ListViewItem clickedItem = listView1.GetItemAt(5, e.Y);
        if (clickedItem != null)
        {
            clickedItem.Selected = true;
            clickedItem.Focused = true;
        }
    }

    // Draws the backgrounds for entire ListView items.
    private void listView1_DrawItem(object sender,
        DrawListViewItemEventArgs e)
    {
        if ((e.State & ListViewItemStates.Selected) != 0)
        {
            // Draw the background and focus rectangle for a selected item.
            e.Graphics.FillRectangle(Brushes.Maroon, e.Bounds);
            e.DrawFocusRectangle();
        }
        else
        {
            // Draw the background for an unselected item.
            using (LinearGradientBrush brush =
                new LinearGradientBrush(e.Bounds, Color.Orange,
                Color.Maroon, LinearGradientMode.Horizontal))
            {
                e.Graphics.FillRectangle(brush, e.Bounds);
            }
        }

        // Draw the item text for views other than the Details view.
        if (listView1.View != View.Details)
        {
            e.DrawText();
        }
    }

    // Draws subitem text and applies content-based formatting.
    private void listView1_DrawSubItem(object sender,
        DrawListViewSubItemEventArgs e)
    {
        TextFormatFlags flags = TextFormatFlags.Left;

        using (StringFormat sf = new StringFormat())
        {
            // Store the column text alignment, letting it default
            // to Left if it has not been set to Center or Right.
            switch (e.Header.TextAlign)
            {
                case HorizontalAlignment.Center:
                    sf.Alignment = StringAlignment.Center;
                    flags = TextFormatFlags.HorizontalCenter;
                    break;
                case HorizontalAlignment.Right:
                    sf.Alignment = StringAlignment.Far;
                    flags = TextFormatFlags.Right;
                    break;
            }

            // Draw the text and background for a subitem with a 
            // negative value. 
            double subItemValue;
            if (e.ColumnIndex > 0 && Double.TryParse(
                e.SubItem.Text, NumberStyles.Currency,
                NumberFormatInfo.CurrentInfo, out subItemValue) &&
                subItemValue < 0)
            {
                // Unless the item is selected, draw the standard 
                // background to make it stand out from the gradient.
                if ((e.ItemState & ListViewItemStates.Selected) == 0)
                {
                    e.DrawBackground();
                }

                // Draw the subitem text in red to highlight it. 
                e.Graphics.DrawString(e.SubItem.Text,
                    listView1.Font, Brushes.Red, e.Bounds, sf);

                return;
            }

            // Draw normal text for a subitem with a nonnegative 
            // or nonnumerical value.
            e.DrawText(flags);
        }
    }

    // Draws column headers.
    private void listView1_DrawColumnHeader(object sender,
        DrawListViewColumnHeaderEventArgs e)
    {
        using (StringFormat sf = new StringFormat())
        {
            // Store the column text alignment, letting it default
            // to Left if it has not been set to Center or Right.
            switch (e.Header.TextAlign)
            {
                case HorizontalAlignment.Center:
                    sf.Alignment = StringAlignment.Center;
                    break;
                case HorizontalAlignment.Right:
                    sf.Alignment = StringAlignment.Far;
                    break;
            }

            // Draw the standard header background.
            e.DrawBackground();

            // Draw the header text.
            using (Font headerFont =
                        new Font("Helvetica", 10, FontStyle.Bold))
            {
                e.Graphics.DrawString(e.Header.Text, headerFont,
                    Brushes.Black, e.Bounds, sf);
            }
        }
        return;
    }

    // Forces each row to repaint itself the first time the mouse moves over 
    // it, compensating for an extra DrawItem event sent by the wrapped 
    // Win32 control.
    private void listView1_MouseMove(object sender, MouseEventArgs e)
    {
        ListViewItem item = listView1.GetItemAt(e.X, e.Y);
        if (item != null && item.Tag == null)
        {
            listView1.Invalidate(item.Bounds);
            item.Tag = "tagged";
        }
    }

}

import System.*;
import System.Drawing.*;
import System.Drawing.Drawing2D.*;
import System.Globalization.*;
import System.Windows.Forms.*;

public class ListViewOwnerDraw extends Form
{
    private ListView myListView;
    private ContextMenu myContextMenu;

    public ListViewOwnerDraw()
    {
        // Create and initialize the ListView control.
        myListView = new ListView();
        myListView.set_BackColor(Color.get_Black());
        myListView.set_ForeColor(Color.get_White());
        myListView.set_Dock(DockStyle.Fill);
        myListView.set_View(View.Details);

        // Add columns to the ListView control.
        myListView.get_Columns().Add("Name", 72, HorizontalAlignment.Center);
        myListView.get_Columns().Add("First", 72, HorizontalAlignment.Center);
        myListView.get_Columns().Add("Second", 72, HorizontalAlignment.Center);
        myListView.get_Columns().Add("Third", 72, HorizontalAlignment.Center);

        // Create items and add them to the ListView control.
        ListViewItem listViewItem1 = new ListViewItem(new String[] 
            { "One", "20", "30", "-40" }, -1);
        ListViewItem listViewItem2 = new ListViewItem(new String[] 
            { "Two", "-250", "145", "37" }, -1);
        ListViewItem listViewItem3 = new ListViewItem(new String[] 
            { "Three", "200", "800", "-1,001" }, -1);
        ListViewItem listViewItem4 = new ListViewItem(new String[] 
            { "Four", "not available", "-2", "100" }, -1);
        myListView.get_Items().AddRange(new ListViewItem[] { listViewItem1, 
            listViewItem2, listViewItem3, listViewItem4 });

        // Create a shortcut menu for changing views and 
        // assign it to the ListView control.
        myContextMenu = new ContextMenu();
        myContextMenu.get_MenuItems().Add("List", 
            new EventHandler(menuItemList_Click));
        myContextMenu.get_MenuItems().Add("Details", 
            new EventHandler(menuItemDetails_Click));
        myListView.set_ContextMenu(myContextMenu);

        // Configure the ListView control for owner-draw and add 
        // handlers for the owner-draw events.
        myListView.set_OwnerDraw(true);
        myListView.add_DrawItem(new DrawListViewItemEventHandler(
            myListView_DrawItem));
        myListView.add_DrawSubItem(new DrawListViewSubItemEventHandler(
            myListView_DrawSubItem));

        // Add a handler for the MouseUp event so an item can be 
        // selected by clicking anywhere along its width.
        myListView.add_MouseUp(new MouseEventHandler(myListView_MouseUp));

        // Initialize the form and add the ListView control to it.
        this.set_ClientSize(new Size(292, 79));
        this.set_FormBorderStyle(get_FormBorderStyle().FixedSingle);
        this.set_MaximizeBox(false);
        this.set_Text("ListView OwnerDraw Example");
        this.get_Controls().Add(myListView);
    } //ListViewOwnerDraw

    // Clean up any resources being used.        
    protected void Dispose(boolean disposing)
    {
        if (disposing) {
            myContextMenu.Dispose();
        }
        super.Dispose(disposing);
    } //Dispose

    /** @attribute STAThread()
     */
    public static void main(String[] args)
    {
        Application.Run(new ListViewOwnerDraw());
    } //main

    // Sets the ListView control to the List view.
    private void menuItemList_Click(Object sender, EventArgs e)
    {
        myListView.set_View(View.List);
    } //menuItemList_Click

    // Sets the ListView control to the Details view.
    private void menuItemDetails_Click(Object sender, EventArgs e)
    {
        myListView.set_View(View.Details);
    } //menuItemDetails_Click

    // Selects and focuses an item when it is clicked anywhere along 
    // its width. The click must normally be on the parent item text.
    private void myListView_MouseUp(Object sender, MouseEventArgs e)
    {
        ListViewItem clickedItem = myListView.GetItemAt(5, e.get_Y());
        if (clickedItem != null) {
            clickedItem.set_Selected(true);
            clickedItem.set_Focused(true);
        }
    } //myListView_MouseUp

    // Draws the backgrounds for the column header row and for entire
    // ListView items.
    private void myListView_DrawItem(Object sender, DrawListViewItemEventArgs e)
    {
        // Draw the background for the column header row.
        if (e.get_ItemIndex() == -1) {
            e.get_Item().set_BackColor(Color.get_Black());
            e.DrawBackground();
        }
        // Draw the background for a selected item.
        else {
            if (Convert.ToInt32((e.get_State() & ListViewItemStates.Selected))
                != 0) {
                e.get_Graphics().FillRectangle(Brushes.get_Maroon(),
                    e.get_Bounds());
                e.DrawFocusRectangle();
            }
            // Draw the background for an unselected item.
            else {
                LinearGradientBrush myBrush = new LinearGradientBrush(
                    e.get_Bounds(), Color.get_Orange(), Color.get_Maroon(),
                    LinearGradientMode.Horizontal);
                try {
                    e.get_Graphics().FillRectangle(myBrush, e.get_Bounds());
                }
                finally {
                    myBrush.Dispose();
                }    
            }
        }
        // Draw the item text for views other than the Details view.
        if (!(((ListView)sender).get_View().Equals(View.Details))) {
            e.DrawText();
        }
    } //myListView_DrawItem

    // Draws subitem text and applies content-based formatting.
    private void myListView_DrawSubItem(Object sender,
        DrawListViewSubItemEventArgs e)
    {
        TextFormatFlags flags = TextFormatFlags.Left;
        StringFormat sf = new StringFormat();
        try {
            // Store the column text alignment, letting it default
            // to Left if it has not been set to Center or Right.
            if (e.get_Header().get_TextAlign().
                Equals(HorizontalAlignment.Center)) {

                sf.set_Alignment(StringAlignment.Center);
                flags = TextFormatFlags.HorizontalCenter;
            }
            else {
                if (e.get_Header().get_TextAlign().
                    Equals(HorizontalAlignment.Right)) {

                    sf.set_Alignment(StringAlignment.Far);
                    flags = TextFormatFlags.Right;
                }
            }
            // Draw the text for a column header.
            if (e.get_ItemIndex() == -1) {
                Font myFont = new Font("Helvetica", 12, FontStyle.Bold);
                try {
                    e.get_Graphics().DrawString(e.get_Item().get_Text(), 
                        myFont, Brushes.get_White(), 
                        new PointF((float)e.get_Bounds().get_X(), 
                        (float)e.get_Bounds().get_Y()), sf);
                }
                finally {
                    myFont.Dispose();
                }
                return;
            }

            // Draw the text and background for a subitem with a 
            // negative value. 
            double subItemValue = 0;
            if (e.get_ColumnIndex() > 0 && System.Double.TryParse(
                e.get_Item().get_SubItems().get_Item(e.get_ColumnIndex()).
                get_Text(), NumberStyles.Currency, 
                NumberFormatInfo.get_CurrentInfo(), subItemValue) 
                && subItemValue < 0) {

                // Unless the item is selected, draw the standard 
                // background to make it stand out from the gradient.
                if (Convert.ToInt32(e.get_ItemState() 
                    & ListViewItemStates.Selected) == 0) {
                    e.DrawBackground();
                }
                // Draw the subitem text in red to highlight it. 
                e.get_Graphics().DrawString(e.get_Item().get_SubItems().
                    get_Item(e.get_ColumnIndex()).get_Text(), 
                    ((ListView)sender).get_Font(), Brushes.get_Red(), 
                    RectangleF.op_Implicit(e.get_Bounds()), sf);

                return;
            }
            // Draw normal text for a subitem with a nonnegative 
            // or nonnumerical value.
            e.DrawText(flags);
        }
        finally {
            sf.Dispose();
        }
    } //myListView_DrawSubItem
} //ListViewOwnerDraw 

System.Object
   System.EventArgs
    System.Windows.Forms.DrawListViewItemEventArgs

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0

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