Files
ObjectListView/FastObjectListView.cs
2017-02-04 13:47:58 +01:00

361 lines
13 KiB
C#

/*
* FastObjectListView - A listview that behaves like an ObjectListView but has the speed of a virtual list
*
* Author: Phillip Piper
* Date: 27/09/2008 9:15 AM
*
* Change log:
* 2012-06-11 JPP - Added more efficient version of FilteredObjects
* v2.5.1
* 2011-04-25 JPP - Fixed problem with removing objects from filtered or sorted list
* v2.4
* 2010-04-05 JPP - Added filtering
* v2.3
* 2009-08-27 JPP - Added GroupingStrategy
* - Added optimized Objects property
* v2.2.1
* 2009-01-07 JPP - Made all public and protected methods virtual
* 2008-09-27 JPP - Separated from ObjectListView.cs
*
* Copyright (C) 2006-2014 Phillip Piper
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* If you wish to use this code in a closed source application, please contact phillip_piper@bigfoot.com.
*/
using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Windows.Forms;
namespace BrightIdeasSoftware
{
/// <summary>
/// A FastObjectListView trades function for speed.
/// </summary>
/// <remarks>
/// <para>On my mid-range laptop, this view builds a list of 10,000 objects in 0.1 seconds,
/// as opposed to a normal ObjectListView which takes 10-15 seconds. Lists of up to 50,000 items should be
/// able to be handled with sub-second response times even on low end machines.</para>
/// <para>
/// A FastObjectListView is implemented as a virtual list with many of the virtual modes limits (e.g. no sorting)
/// fixed through coding. There are some functions that simply cannot be provided. Specifically, a FastObjectListView cannot:
/// <list type="bullet">
/// <item><description>use Tile view</description></item>
/// <item><description>show groups on XP</description></item>
/// </list>
/// </para>
/// </remarks>
public class FastObjectListView : VirtualObjectListView
{
/// <summary>
/// Make a FastObjectListView
/// </summary>
public FastObjectListView() {
this.VirtualListDataSource = new FastObjectListDataSource(this);
this.GroupingStrategy = new FastListGroupingStrategy();
}
/// <summary>
/// Gets the collection of objects that survive any filtering that may be in place.
/// </summary>
[Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public override IEnumerable FilteredObjects {
get {
// This is much faster than the base method
return ((FastObjectListDataSource)this.VirtualListDataSource).FilteredObjectList;
}
}
/// <summary>
/// Get/set the collection of objects that this list will show
/// </summary>
/// <remarks>
/// <para>
/// The contents of the control will be updated immediately after setting this property.
/// </para>
/// <para>This method preserves selection, if possible. Use SetObjects() if
/// you do not want to preserve the selection. Preserving selection is the slowest part of this
/// code and performance is O(n) where n is the number of selected rows.</para>
/// <para>This method is not thread safe.</para>
/// </remarks>
[Browsable(false),
DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
public override IEnumerable Objects {
get {
// This is much faster than the base method
return ((FastObjectListDataSource)this.VirtualListDataSource).ObjectList;
}
set { base.Objects = value; }
}
/// <summary>
/// Remove any sorting and revert to the given order of the model objects
/// </summary>
/// <remarks>To be really honest, Unsort() doesn't work on FastObjectListViews since
/// the original ordering of model objects is lost when Sort() is called. So this method
/// effectively just turns off sorting.</remarks>
public override void Unsort() {
this.ShowGroups = false;
this.PrimarySortColumn = null;
this.PrimarySortOrder = SortOrder.None;
this.SetObjects(this.Objects);
}
}
/// <summary>
/// Provide a data source for a FastObjectListView
/// </summary>
/// <remarks>
/// This class isn't intended to be used directly, but it is left as a public
/// class just in case someone wants to subclass it.
/// </remarks>
public class FastObjectListDataSource : AbstractVirtualListDataSource
{
/// <summary>
/// Create a FastObjectListDataSource
/// </summary>
/// <param name="listView"></param>
public FastObjectListDataSource(FastObjectListView listView)
: base(listView) {
}
#region IVirtualListDataSource Members
/// <summary>
/// Get n'th object
/// </summary>
/// <param name="n"></param>
/// <returns></returns>
public override object GetNthObject(int n) {
if (n >= 0 && n < this.filteredObjectList.Count)
return this.filteredObjectList[n];
return null;
}
/// <summary>
/// How many items are in the data source
/// </summary>
/// <returns></returns>
public override int GetObjectCount() {
return this.filteredObjectList.Count;
}
/// <summary>
/// Get the index of the given model
/// </summary>
/// <param name="model"></param>
/// <returns></returns>
public override int GetObjectIndex(object model) {
int index;
if (model != null && this.objectsToIndexMap.TryGetValue(model, out index))
return index;
return -1;
}
/// <summary>
///
/// </summary>
/// <param name="text"></param>
/// <param name="first"></param>
/// <param name="last"></param>
/// <param name="column"></param>
/// <returns></returns>
public override int SearchText(string text, int first, int last, OLVColumn column) {
if (first <= last) {
for (int i = first; i <= last; i++) {
string data = column.GetStringValue(this.listView.GetNthItemInDisplayOrder(i).RowObject);
if (data.StartsWith(text, StringComparison.CurrentCultureIgnoreCase))
return i;
}
} else {
for (int i = first; i >= last; i--) {
string data = column.GetStringValue(this.listView.GetNthItemInDisplayOrder(i).RowObject);
if (data.StartsWith(text, StringComparison.CurrentCultureIgnoreCase))
return i;
}
}
return -1;
}
/// <summary>
///
/// </summary>
/// <param name="column"></param>
/// <param name="sortOrder"></param>
public override void Sort(OLVColumn column, SortOrder sortOrder) {
if (sortOrder != SortOrder.None) {
ModelObjectComparer comparer = new ModelObjectComparer(column, sortOrder, this.listView.SecondarySortColumn, this.listView.SecondarySortOrder);
this.fullObjectList.Sort(comparer);
this.filteredObjectList.Sort(comparer);
}
this.RebuildIndexMap();
}
/// <summary>
///
/// </summary>
/// <param name="modelObjects"></param>
public override void AddObjects(ICollection modelObjects) {
foreach (object modelObject in modelObjects) {
if (modelObject != null)
this.fullObjectList.Add(modelObject);
}
this.FilterObjects();
this.RebuildIndexMap();
}
/// <summary>
/// Remove the given collection of models from this source.
/// </summary>
/// <param name="modelObjects"></param>
public override void RemoveObjects(ICollection modelObjects) {
List<int> indicesToRemove = new List<int>();
foreach (object modelObject in modelObjects) {
int i = this.GetObjectIndex(modelObject);
if (i >= 0)
indicesToRemove.Add(i);
// Remove the objects from the unfiltered list
this.fullObjectList.Remove(modelObject);
}
// Sort the indices from highest to lowest so that we
// remove latter ones before earlier ones. In this way, the
// indices of the rows doesn't change after the deletes.
indicesToRemove.Sort();
indicesToRemove.Reverse();
foreach (int i in indicesToRemove)
this.listView.SelectedIndices.Remove(i);
this.FilterObjects();
this.RebuildIndexMap();
}
/// <summary>
///
/// </summary>
/// <param name="collection"></param>
public override void SetObjects(IEnumerable collection) {
ArrayList newObjects = ObjectListView.EnumerableToArray(collection, true);
this.fullObjectList = newObjects;
this.FilterObjects();
this.RebuildIndexMap();
}
/// <summary>
/// Update/replace the nth object with the given object
/// </summary>
/// <param name="index"></param>
/// <param name="modelObject"></param>
public override void UpdateObject(int index, object modelObject) {
if (index < 0 || index >= this.filteredObjectList.Count)
return;
int i = this.fullObjectList.IndexOf(this.filteredObjectList[index]);
if (i < 0)
return;
this.fullObjectList[i] = modelObject;
this.filteredObjectList[index] = modelObject;
this.objectsToIndexMap[modelObject] = index;
}
private ArrayList fullObjectList = new ArrayList();
private ArrayList filteredObjectList = new ArrayList();
private IModelFilter modelFilter;
private IListFilter listFilter;
#endregion
#region IFilterableDataSource Members
/// <summary>
/// Apply the given filters to this data source. One or both may be null.
/// </summary>
/// <param name="iModelFilter"></param>
/// <param name="iListFilter"></param>
public override void ApplyFilters(IModelFilter iModelFilter, IListFilter iListFilter) {
this.modelFilter = iModelFilter;
this.listFilter = iListFilter;
this.SetObjects(this.fullObjectList);
}
#endregion
#region Implementation
/// <summary>
/// Gets the full list of objects being used for this fast list.
/// This list is unfiltered.
/// </summary>
public ArrayList ObjectList {
get { return fullObjectList; }
}
/// <summary>
/// Gets the list of objects from ObjectList which survive any installed filters.
/// </summary>
public ArrayList FilteredObjectList {
get { return filteredObjectList; }
}
/// <summary>
/// Rebuild the map that remembers which model object is displayed at which line
/// </summary>
protected void RebuildIndexMap() {
this.objectsToIndexMap.Clear();
for (int i = 0; i < this.filteredObjectList.Count; i++)
this.objectsToIndexMap[this.filteredObjectList[i]] = i;
}
readonly Dictionary<Object, int> objectsToIndexMap = new Dictionary<Object, int>();
/// <summary>
/// Build our filtered list from our full list.
/// </summary>
protected void FilterObjects() {
if (!this.listView.UseFiltering || (this.modelFilter == null && this.listFilter == null)) {
this.filteredObjectList = new ArrayList(this.fullObjectList);
return;
}
IEnumerable objects = (this.listFilter == null) ?
this.fullObjectList : this.listFilter.Filter(this.fullObjectList);
// Apply the object filter if there is one
if (this.modelFilter == null) {
this.filteredObjectList = ObjectListView.EnumerableToArray(objects, false);
} else {
this.filteredObjectList = new ArrayList();
foreach (object model in objects) {
if (this.modelFilter.Filter(model))
this.filteredObjectList.Add(model);
}
}
}
#endregion
}
}