稍改进过的ListView

永久禁言 · 发表于 2013-2-22 02:02:00

改进了一点点的ListView，数据多不会闪。可以拖动行来进行排序了。
要启用拖放行，设置一下 AllowRecoder为true即可。另外多行选择=false

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Forms;
using System.Drawing;
using System.ComponentModel;
using System.Collections;
namespace Emao_ListView
{
public class MyListView : System.Windows.Forms.ListView
{
#region Private Members
private ListViewItem m_previousItem;
private bool m_allowReorder;
private Color m_lineColor;
#endregion
#region Public Properties
[Category("Behavior")]
public bool AllowReorder
{
get { return m_allowReorder; }
set { m_allowReorder = value; }
}
[Category("Appearance")]
public Color LineColor
{
get { return m_lineColor; }
set { m_lineColor = value; }
}
#endregion
#region Protected and Public Methods
public MyListView()
: base()
{
this.FullRowSelect = true;
this.GridLines = true;
this.View = View.Details;
m_allowReorder = true;
m_lineColor = Color.Red;
SetStyle(System.Windows.Forms.ControlStyles.DoubleBuffer |
System.Windows.Forms.ControlStyles.OptimizedDoubleBuffer |
System.Windows.Forms.ControlStyles.AllPaintingInWmPaint,
true);
UpdateStyles();
}
protected override void OnDragDrop(DragEventArgs drgevent)
{
if (!m_allowReorder)
{
base.OnDragDrop(drgevent);
return;
}
// get the currently hovered row that the items will be dragged to
Point clientPoint = base.PointToClient(new Point(drgevent.X, drgevent.Y));
ListViewItem hoverItem = base.GetItemAt(clientPoint.X, clientPoint.Y);
if (!drgevent.Data.GetDataPresent(typeof(DragItemData).ToString()) || ((DragItemData)drgevent.Data.GetData(typeof(DragItemData).ToString())).ListView == null || ((DragItemData)drgevent.Data.GetData(typeof(DragItemData).ToString())).DragItems.Count == 0)
return;
// retrieve the drag item data
DragItemData data = (DragItemData)drgevent.Data.GetData(typeof(DragItemData).ToString());
if (hoverItem == null)
{
// the user does not wish to re-order the items, just append to the end
for (int i = 0; i < data.DragItems.Count; i++)
{
ListViewItem newItem = (ListViewItem)data.DragItems[i];
base.Items.Add(newItem);
}
}
else
{
// the user wishes to re-order the items
// get the index of the hover item
int hoverIndex = hoverItem.Index;
// determine if the items to be dropped are from
// this list view. If they are, perform a hack
// to increment the hover index so that the items
// get moved properly.
if (this == data.ListView)
{
if (hoverIndex > base.SelectedItems[0].Index)
hoverIndex++;
}
// insert the new items into the list view
// by inserting the items reversely from the array list
for (int i = data.DragItems.Count - 1; i >= 0; i--)
{
ListViewItem newItem = (ListViewItem)data.DragItems[i];
base.Items.Insert(hoverIndex, newItem);
}
}
// remove all the selected items from the previous list view
// if the list view was found
if (data.ListView != null)
{
foreach (ListViewItem itemToRemove in data.ListView.SelectedItems)
{
data.ListView.Items.Remove(itemToRemove);
}
}
// set the back color of the previous item, then nullify it
if (m_previousItem != null)
{
m_previousItem = null;
}
this.Invalidate();
// call the base on drag drop to raise the event
base.OnDragDrop(drgevent);
}
protected override void OnDragOver(DragEventArgs drgevent)
{
if (!m_allowReorder)
{
base.OnDragOver(drgevent);
return;
}
if (!drgevent.Data.GetDataPresent(typeof(DragItemData).ToString()))
{
// the item(s) being dragged do not have any data associated
drgevent.Effect = DragDropEffects.None;
return;
}
if (base.Items.Count > 0)
{
// get the currently hovered row that the items will be dragged to
Point clientPoint = base.PointToClient(new Point(drgevent.X, drgevent.Y));
ListViewItem hoverItem = base.GetItemAt(clientPoint.X, clientPoint.Y);
Graphics g = this.CreateGraphics();
if (hoverItem == null)
{
//MessageBox.Show(base.GetChildAtPoint(new Point(clientPoint.X, clientPoint.Y)).GetType().ToString());
// no item was found, so no drop should take place
drgevent.Effect = DragDropEffects.Move;
if (m_previousItem != null)
{
m_previousItem = null;
Invalidate();
}
hoverItem = base.Items[base.Items.Count - 1];
if (this.View == View.Details || this.View == View.List)
{
g.DrawLine(new Pen(m_lineColor, 2), new Point(hoverItem.Bounds.X, hoverItem.Bounds.Y + hoverItem.Bounds.Height), new Point(hoverItem.Bounds.X + this.Bounds.Width, hoverItem.Bounds.Y + hoverItem.Bounds.Height));
g.FillPolygon(new SolidBrush(m_lineColor), new Point[] { new Point(hoverItem.Bounds.X, hoverItem.Bounds.Y + hoverItem.Bounds.Height - 5), new Point(hoverItem.Bounds.X + 5, hoverItem.Bounds.Y + hoverItem.Bounds.Height), new Point(hoverItem.Bounds.X, hoverItem.Bounds.Y + hoverItem.Bounds.Height + 5) });
g.FillPolygon(new SolidBrush(m_lineColor), new Point[] { new Point(this.Bounds.Width - 4, hoverItem.Bounds.Y + hoverItem.Bounds.Height - 5), new Point(this.Bounds.Width - 9, hoverItem.Bounds.Y + hoverItem.Bounds.Height), new Point(this.Bounds.Width - 4, hoverItem.Bounds.Y + hoverItem.Bounds.Height + 5) });
}
else
{
g.DrawLine(new Pen(m_lineColor, 2), new Point(hoverItem.Bounds.X + hoverItem.Bounds.Width, hoverItem.Bounds.Y), new Point(hoverItem.Bounds.X + hoverItem.Bounds.Width, hoverItem.Bounds.Y + hoverItem.Bounds.Height));
g.FillPolygon(new SolidBrush(m_lineColor), new Point[] { new Point(hoverItem.Bounds.X + hoverItem.Bounds.Width - 5, hoverItem.Bounds.Y), new Point(hoverItem.Bounds.X + hoverItem.Bounds.Width + 5, hoverItem.Bounds.Y), new Point(hoverItem.Bounds.X + hoverItem.Bounds.Width, hoverItem.Bounds.Y + 5) });
g.FillPolygon(new SolidBrush(m_lineColor), new Point[] { new Point(hoverItem.Bounds.X + hoverItem.Bounds.Width - 5, hoverItem.Bounds.Y + hoverItem.Bounds.Height), new Point(hoverItem.Bounds.X + hoverItem.Bounds.Width + 5, hoverItem.Bounds.Y + hoverItem.Bounds.Height), new Point(hoverItem.Bounds.X + hoverItem.Bounds.Width, hoverItem.Bounds.Y + hoverItem.Bounds.Height - 5) });
}
// call the base OnDragOver event
base.OnDragOver(drgevent);
return;
}
// determine if the user is currently hovering over a new
// item. If so, set the previous item's back color back
// to the default color.
if ((m_previousItem != null && m_previousItem != hoverItem) || m_previousItem == null)
{
this.Invalidate();
}
// set the background color of the item being hovered
// and assign the previous item to the item being hovered
//hoverItem.BackColor = Color.Beige;
m_previousItem = hoverItem;
if (this.View == View.Details || this.View == View.List)
{
g.DrawLine(new Pen(m_lineColor, 2), new Point(hoverItem.Bounds.X, hoverItem.Bounds.Y), new Point(hoverItem.Bounds.X + this.Bounds.Width, hoverItem.Bounds.Y));
g.FillPolygon(new SolidBrush(m_lineColor), new Point[] { new Point(hoverItem.Bounds.X, hoverItem.Bounds.Y - 5), new Point(hoverItem.Bounds.X + 5, hoverItem.Bounds.Y), new Point(hoverItem.Bounds.X, hoverItem.Bounds.Y + 5) });
g.FillPolygon(new SolidBrush(m_lineColor), new Point[] { new Point(this.Bounds.Width - 4, hoverItem.Bounds.Y - 5), new Point(this.Bounds.Width - 9, hoverItem.Bounds.Y), new Point(this.Bounds.Width - 4, hoverItem.Bounds.Y + 5) });
}
else
{
g.DrawLine(new Pen(m_lineColor, 2), new Point(hoverItem.Bounds.X, hoverItem.Bounds.Y), new Point(hoverItem.Bounds.X, hoverItem.Bounds.Y + hoverItem.Bounds.Height));
g.FillPolygon(new SolidBrush(m_lineColor), new Point[] { new Point(hoverItem.Bounds.X - 5, hoverItem.Bounds.Y), new Point(hoverItem.Bounds.X + 5, hoverItem.Bounds.Y), new Point(hoverItem.Bounds.X, hoverItem.Bounds.Y + 5) });
g.FillPolygon(new SolidBrush(m_lineColor), new Point[] { new Point(hoverItem.Bounds.X - 5, hoverItem.Bounds.Y + hoverItem.Bounds.Height), new Point(hoverItem.Bounds.X + 5, hoverItem.Bounds.Y + hoverItem.Bounds.Height), new Point(hoverItem.Bounds.X, hoverItem.Bounds.Y + hoverItem.Bounds.Height - 5) });
}
// go through each of the selected items, and if any of the
// selected items have the same index as the item being
// hovered, disable dropping.
foreach (ListViewItem itemToMove in base.SelectedItems)
{
if (itemToMove.Index == hoverItem.Index)
{
drgevent.Effect = DragDropEffects.None;
hoverItem.EnsureVisible();
return;
}
}
// ensure that the hover item is visible
hoverItem.EnsureVisible();
}
// everything is fine, allow the user to move the items
drgevent.Effect = DragDropEffects.Move;
// call the base OnDragOver event
base.OnDragOver(drgevent);
}
protected override void OnDragEnter(DragEventArgs drgevent)
{
if (!m_allowReorder)
{
base.OnDragEnter(drgevent);
return;
}
if (!drgevent.Data.GetDataPresent(typeof(DragItemData).ToString()))
{
// the item(s) being dragged do not have any data associated
drgevent.Effect = DragDropEffects.None;
return;
}
// everything is fine, allow the user to move the items
drgevent.Effect = DragDropEffects.Move;
// call the base OnDragEnter event
base.OnDragEnter(drgevent);
}
protected override void OnItemDrag(ItemDragEventArgs e)
{
if (!m_allowReorder)
{
base.OnItemDrag(e);
return;
}
// call the DoDragDrop method
base.DoDragDrop(GetDataForDragDrop(), DragDropEffects.Move);
// call the base OnItemDrag event
base.OnItemDrag(e);
}
protected override void OnLostFocus(EventArgs e)
{
// reset the selected items background and remove the previous item
ResetOutOfRange();
Invalidate();
// call the OnLostFocus event
base.OnLostFocus(e);
}
protected override void OnDragLeave(EventArgs e)
{
// reset the selected items background and remove the previous item
ResetOutOfRange();
Invalidate();
// call the base OnDragLeave event
base.OnDragLeave(e);
}
#endregion
#region Private Methods
private DragItemData GetDataForDragDrop()
{
// create a drag item data object that will be used to pass along with the drag and drop
DragItemData data = new DragItemData(this);
// go through each of the selected items and
// add them to the drag items collection
// by creating a clone of the list item
foreach (ListViewItem item in this.SelectedItems)
{
data.DragItems.Add(item.Clone());
}
return data;
}
private void ResetOutOfRange()
{
// determine if the previous item exists,
// if it does, reset the background and release
// the previous item
if (m_previousItem != null)
{
m_previousItem = null;
}
}
#endregion
#region DragItemData Class
private class DragItemData
{
#region Private Members
private MyListView m_listView;
private ArrayList m_dragItems;
#endregion
#region Public Properties
public MyListView ListView
{
get { return m_listView; }
}
public ArrayList DragItems
{
get { return m_dragItems; }
}
#endregion
#region Public Methods and Implementation
public DragItemData(MyListView listView)
{
m_listView = listView;
m_dragItems = new ArrayList();
}
#endregion
}
#endregion
}
}

复制代码

shiguangkeji · 发表于 2016-6-10 11:00:10

卡不懂。。。。。

Keyword · 发表于 2013-5-1 18:45:32

牛逼啊大婶不愧是大神啊

bjxy87 · 发表于 2013-2-22 08:37:07

依然支持的一个下载点不容易

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[C#源码] 稍改进过的ListView