Code:
/ Dotnetfx_Vista_SP2 / Dotnetfx_Vista_SP2 / 8.0.50727.4016 / DEVDIV / depot / DevDiv / releases / whidbey / NetFxQFE / ndp / fx / src / WinForms / Managed / System / WinForms / CurrencyManager.cs / 1 / CurrencyManager.cs
//------------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//-----------------------------------------------------------------------------
namespace System.Windows.Forms {
using System;
using Microsoft.Win32;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.ComponentModel;
using System.Collections;
using System.Reflection;
using System.Globalization;
///
/// Manages the position and bindings of a
/// list.
///
public class CurrencyManager : BindingManagerBase {
private Object dataSource;
private IList list;
private bool bound = false;
private bool shouldBind = true;
///
///
[
SuppressMessage("Microsoft.Design", "CA1051:DoNotDeclareVisibleInstanceFields") // We can't make CurrencyManager.listposition internal
// because it would be a breaking change.
]
protected int listposition = -1;
private int lastGoodKnownRow = -1;
private bool pullingData = false;
private bool inChangeRecordState = false;
private bool suspendPushDataInCurrentChanged = false;
// private bool onItemChangedCalled = false;
// private EventHandler onCurrentChanged;
// private CurrentChangingEventHandler onCurrentChanging;
private ItemChangedEventHandler onItemChanged;
private ListChangedEventHandler onListChanged;
private ItemChangedEventArgs resetEvent = new ItemChangedEventArgs(-1);
private EventHandler onMetaDataChangedHandler;
///
/// Gets the type of the list.
///
protected Type finalType;
///
/// Occurs when the
/// current item has been
/// altered.
///
[SRCategory(SR.CatData)]
public event ItemChangedEventHandler ItemChanged {
add {
onItemChanged += value;
}
remove {
onItemChanged -= value;
}
}
///
///
[
SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors") // If the constructor does not set the dataSource
// it would be a breaking change.
]
internal CurrencyManager(Object dataSource) {
SetDataSource(dataSource);
}
///
/// Gets a value indicating
/// whether items can be added to the list.
///
internal bool AllowAdd {
get {
if (list is IBindingList) {
return ((IBindingList)list).AllowNew;
}
if (list == null)
return false;
return !list.IsReadOnly && !list.IsFixedSize;
}
}
///
/// Gets a value
/// indicating whether edits to the list are allowed.
///
internal bool AllowEdit {
get {
if (list is IBindingList) {
return ((IBindingList)list).AllowEdit;
}
if (list == null)
return false;
return !list.IsReadOnly;
}
}
///
/// Gets a value indicating whether items can be removed from the list.
///
internal bool AllowRemove {
get {
if (list is IBindingList) {
return ((IBindingList)list).AllowRemove;
}
if (list == null)
return false;
return !list.IsReadOnly && !list.IsFixedSize;
}
}
///
/// Gets the number of items in the list.
///
public override int Count {
get {
if (list == null)
return 0;
else
return list.Count;
}
}
///
/// Gets the current item in the list.
///
public override Object Current {
get {
return this[Position];
}
}
internal override Type BindType {
get {
return ListBindingHelper.GetListItemType(this.List);
}
}
///
/// Gets the data source of the list.
///
internal override Object DataSource {
get {
return dataSource;
}
}
internal override void SetDataSource(Object dataSource) {
if (this.dataSource != dataSource) {
Release();
this.dataSource = dataSource;
this.list = null;
this.finalType = null;
Object tempList = dataSource;
if (tempList is Array) {
finalType = tempList.GetType();
tempList = (Array)tempList;
}
if (tempList is IListSource) {
tempList = ((IListSource)tempList).GetList();
}
if (tempList is IList) {
if (finalType == null) {
finalType = tempList.GetType();
}
this.list = (IList)tempList;
WireEvents(list);
if (list.Count > 0 )
listposition = 0;
else
listposition = -1;
OnItemChanged(resetEvent);
OnListChanged(new ListChangedEventArgs(ListChangedType.Reset, -1, -1));
UpdateIsBinding();
}
else {
if (tempList == null) {
throw new ArgumentNullException("dataSource");
}
throw new ArgumentException(SR.GetString(SR.ListManagerSetDataSource, tempList.GetType().FullName), "dataSource");
}
}
}
///
/// Gets a value indicating whether the list is bound to a data source.
///
internal override bool IsBinding {
get {
return bound;
}
}
// The DataGridView needs this.
internal bool ShouldBind {
get {
return shouldBind;
}
}
///
/// Gets the list as an object.
///
public IList List {
get {
// NOTE: do not change this to throw an exception if the list is not IBindingList.
// doing this will cause a major performance hit when wiring the
// dataGrid to listen for MetaDataChanged events from the IBindingList
// (basically we would have to wrap all calls to CurrencyManager::List with
// a try/catch block.)
//
return list;
}
}
///
/// Gets or sets the position you are at within the list.
///
public override int Position {
get {
return listposition;
}
set {
if (listposition == -1)
return;
if (value < 0)
value = 0;
int count = list.Count;
if (value >= count)
value = count - 1;
ChangeRecordState(value, listposition != value, true, true, false); // true for endCurrentEdit
// true for firingPositionChange notification
// data will be pulled from controls anyway.
}
}
///
/// Gets or sets the object at the specified index.
///
internal Object this[int index] {
get {
if (index < 0 || index >= list.Count) {
throw new IndexOutOfRangeException(SR.GetString(SR.ListManagerNoValue, index.ToString(CultureInfo.CurrentCulture)));
}
return list[index];
}
set {
if (index < 0 || index >= list.Count) {
throw new IndexOutOfRangeException(SR.GetString(SR.ListManagerNoValue, index.ToString(CultureInfo.CurrentCulture)));
}
list[index] = value;
}
}
///
/// [To be supplied.]
///
public override void AddNew() {
IBindingList ibl = list as IBindingList;
if (ibl != null) {
ibl.AddNew();
}
else {
// If the list is not IBindingList, then throw an exception:
throw new NotSupportedException(SR.GetString(SR.CurrencyManagerCantAddNew));
}
ChangeRecordState(list.Count - 1, (Position != list.Count - 1), (Position != list.Count - 1), true, true); // true for firingPositionChangeNotification
// true for pulling data from the controls
}
///
/// Cancels the current edit operation.
///
public override void CancelCurrentEdit() {
if (Count > 0) {
Object item = (Position >= 0 && Position < list.Count) ? list[Position] : null;
// onItemChangedCalled = false;
IEditableObject iEditableItem = item as IEditableObject;
if (iEditableItem != null) {
iEditableItem.CancelEdit();
}
ICancelAddNew iListWithCancelAddNewSupport = list as ICancelAddNew;
if (iListWithCancelAddNewSupport != null) {
iListWithCancelAddNewSupport.CancelNew(this.Position);
}
OnItemChanged(new ItemChangedEventArgs(Position));
if (this.Position != -1) {
OnListChanged(new ListChangedEventArgs(ListChangedType.ItemChanged, this.Position));
}
}
}
private void ChangeRecordState(int newPosition, bool validating, bool endCurrentEdit, bool firePositionChange, bool pullData) {
if (newPosition == -1 && list.Count == 0) {
if (listposition != -1) {
this.listposition = -1;
OnPositionChanged(EventArgs.Empty);
}
return;
}
if ((newPosition < 0 || newPosition >= Count) && this.IsBinding) {
throw new IndexOutOfRangeException(SR.GetString(SR.ListManagerBadPosition));
}
// if PushData fails in the OnCurrentChanged and there was a lastGoodKnownRow
// then the position does not change, so we should not fire the OnPositionChanged
// event;
// this is why we have to cache the old position and compare that w/ the position that
// the user will want to navigate to
int oldPosition = listposition;
if (endCurrentEdit) {
// Do not PushData when pro. See ASURT 65095.
inChangeRecordState = true;
try {
EndCurrentEdit();
} finally {
inChangeRecordState = false;
}
}
// we pull the data from the controls only when the ListManager changes the list. when the backEnd changes the list we do not
// pull the data from the controls
if (validating && pullData) {
CurrencyManager_PullData();
}
// vsWhidbey 425961: EndCurrentEdit or PullData can cause the list managed by the CurrencyManager to shrink.
this.listposition = Math.Min(newPosition, Count - 1);
if (validating) {
OnCurrentChanged(EventArgs.Empty);
}
bool positionChanging = (oldPosition != listposition);
if (positionChanging && firePositionChange) {
OnPositionChanged(EventArgs.Empty);
}
}
///
/// Throws an exception if there is no list.
///
protected void CheckEmpty() {
if (dataSource == null || list == null || list.Count == 0) {
throw new InvalidOperationException(SR.GetString(SR.ListManagerEmptyList));
}
}
// will return true if this function changes the position in the list
private bool CurrencyManager_PushData() {
if (pullingData)
return false;
int initialPosition = listposition;
if (lastGoodKnownRow == -1) {
try {
PushData();
}
catch (Exception ex) {
OnDataError(ex);
// get the first item in the list that is good to push data
// for now, we assume that there is a row in the backEnd
// that is good for all the bindings.
FindGoodRow();
}
lastGoodKnownRow = listposition;
} else {
try {
PushData();
}
catch (Exception ex) {
OnDataError(ex);
listposition = lastGoodKnownRow;
PushData();
}
lastGoodKnownRow = listposition;
}
return initialPosition != listposition;
}
private bool CurrencyManager_PullData() {
bool success = true;
pullingData = true;
try {
PullData(out success);
} finally {
pullingData = false;
}
return success;
}
///
/// [To be supplied.]
///
public override void RemoveAt(int index) {
list.RemoveAt(index);
}
///
/// Ends the current edit operation.
///
public override void EndCurrentEdit() {
if (Count > 0) {
bool success = CurrencyManager_PullData();
if (success) {
Object item = (Position >= 0 && Position < list.Count) ? list[Position] : null;
IEditableObject iEditableItem = item as IEditableObject;
if (iEditableItem != null) {
iEditableItem.EndEdit();
}
ICancelAddNew iListWithCancelAddNewSupport = list as ICancelAddNew;
if (iListWithCancelAddNewSupport != null) {
iListWithCancelAddNewSupport.EndNew(this.Position);
}
}
}
}
private void FindGoodRow() {
int rowCount = this.list.Count;
for (int i = 0; i < rowCount; i++) {
listposition = i;
try {
PushData();
}
catch (Exception ex) {
OnDataError(ex);
continue;
}
listposition = i;
return;
}
// if we got here, the list did not contain any rows suitable for the bindings
// suspend binding and throw an exception
SuspendBinding();
throw new InvalidOperationException(SR.GetString(SR.DataBindingPushDataException));
}
///
/// Sets the column to sort by, and the direction of the sort.
///
internal void SetSort(PropertyDescriptor property, ListSortDirection sortDirection) {
if (list is IBindingList && ((IBindingList)list).SupportsSorting) {
((IBindingList)list).ApplySort(property, sortDirection);
}
}
///
/// Gets a
///
internal PropertyDescriptor GetSortProperty() {
if ((list is IBindingList) && ((IBindingList)list).SupportsSorting) {
return ((IBindingList)list).SortProperty;
}
return null;
}
///
/// Gets the sort direction of a list.
///
internal ListSortDirection GetSortDirection() {
if ((list is IBindingList) && ((IBindingList)list).SupportsSorting) {
return ((IBindingList)list).SortDirection;
}
return ListSortDirection.Ascending;
}
///
/// Find the position of a desired list item.
///
internal int Find(PropertyDescriptor property, Object key, bool keepIndex) {
if (key == null)
throw new ArgumentNullException("key");
if (property != null && (list is IBindingList) && ((IBindingList)list).SupportsSearching) {
return ((IBindingList)list).Find(property, key);
}
for (int i = 0; i < list.Count; i++) {
object value = property.GetValue(list[i]);
if (key.Equals(value)) {
return i;
}
}
return -1;
}
///
/// Gets the name of the list.
///
internal override string GetListName() {
if (list is ITypedList) {
return ((ITypedList)list).GetListName(null);
}
else {
return finalType.Name;
}
}
///
/// Gets the name of the specified list.
///
protected internal override string GetListName(ArrayList listAccessors) {
if (list is ITypedList) {
PropertyDescriptor[] properties = new PropertyDescriptor[listAccessors.Count];
listAccessors.CopyTo(properties, 0);
return ((ITypedList)list).GetListName(properties);
}
return "";
}
///
///
internal override PropertyDescriptorCollection GetItemProperties(PropertyDescriptor[] listAccessors) {
return ListBindingHelper.GetListItemProperties(this.list, listAccessors);
}
///
/// Gets the
///
public override PropertyDescriptorCollection GetItemProperties() {
return GetItemProperties(null);
}
///
/// Gets the
///
private void List_ListChanged(Object sender, System.ComponentModel.ListChangedEventArgs e) {
// If you change the assert below, better change the
// code in the OnCurrentChanged that deals w/ firing the OnCurrentChanged event
Debug.Assert(lastGoodKnownRow == -1 || lastGoodKnownRow == listposition, "if we have a valid lastGoodKnownRow, then it should equal the position in the list");
// bug 139627: when the data view fires an ItemMoved event where the old position is negative, that really means
// that a row was added
// bug 156236: when the data view fires an ItemMoved event where the new position is negative, that really means
// that a row was deleted
// dbe is our DataBindingEvent
//
ListChangedEventArgs dbe;
if (e.ListChangedType == ListChangedType.ItemMoved && e.OldIndex < 0) {
dbe = new ListChangedEventArgs(ListChangedType.ItemAdded, e.NewIndex, e.OldIndex);
} else if (e.ListChangedType == ListChangedType.ItemMoved && e.NewIndex < 0) {
dbe = new ListChangedEventArgs(ListChangedType.ItemDeleted, e.OldIndex, e.NewIndex);
} else {
dbe = e;
}
int oldposition = listposition;
UpdateLastGoodKnownRow(dbe);
UpdateIsBinding();
if (list.Count == 0) {
listposition = -1;
if (oldposition != -1) {
// if we used to have a current row, but not any more, then report current as changed
OnPositionChanged(EventArgs.Empty);
OnCurrentChanged(EventArgs.Empty);
}
if (dbe.ListChangedType == System.ComponentModel.ListChangedType.Reset && e.NewIndex == -1) {
// if the list is reset, then let our users know about it.
OnItemChanged(resetEvent);
}
if (dbe.ListChangedType == System.ComponentModel.ListChangedType.ItemDeleted) {
// if the list is reset, then let our users know about it.
OnItemChanged(resetEvent);
}
// we should still fire meta data change notification even when the list is empty
if (e.ListChangedType == System.ComponentModel.ListChangedType.PropertyDescriptorAdded ||
e.ListChangedType == System.ComponentModel.ListChangedType.PropertyDescriptorDeleted ||
e.ListChangedType == System.ComponentModel.ListChangedType.PropertyDescriptorChanged)
OnMetaDataChanged(EventArgs.Empty);
//
OnListChanged(dbe);
return;
}
suspendPushDataInCurrentChanged = true;
try {
switch (dbe.ListChangedType) {
case System.ComponentModel.ListChangedType.Reset:
Debug.WriteLineIf(CompModSwitches.DataCursor.TraceVerbose, "System.ComponentModel.ListChangedType.Reset Position: " + Position + " Count: " + list.Count);
if (listposition == -1 && list.Count > 0)
ChangeRecordState(0, true, false, true, false); // last false: we don't pull the data from the control when DM changes
else
ChangeRecordState(Math.Min(listposition,list.Count - 1), true, false, true, false);
UpdateIsBinding(/*raiseItemChangedEvent:*/ false);
OnItemChanged(resetEvent);
break;
case System.ComponentModel.ListChangedType.ItemAdded:
Debug.WriteLineIf(CompModSwitches.DataCursor.TraceVerbose, "System.ComponentModel.ListChangedType.ItemAdded " + dbe.NewIndex.ToString(CultureInfo.InvariantCulture));
if (dbe.NewIndex <= listposition && listposition < list.Count - 1) {
// this means the current row just moved down by one.
// the position changes, so end the current edit
ChangeRecordState(listposition + 1, true, true, listposition != list.Count - 2, false);
UpdateIsBinding();
// 85426: refresh the list after we got the item added event
OnItemChanged(resetEvent);
// 84460: when we get the itemAdded, and the position was at the end
// of the list, do the right thing and notify the positionChanged after refreshing the list
if (listposition == list.Count - 1)
OnPositionChanged(EventArgs.Empty);
break;
} else if (dbe.NewIndex == this.listposition && this.listposition == list.Count - 1 && this.listposition != -1) {
// The CurrencyManager has a non-empty list.
// The position inside the currency manager is at the end of the list and the list still fired an ItemAdded event.
// This could be the second ItemAdded event that the DataView fires to signal that the AddNew operation was commited.
// We need to fire CurrentItemChanged event so that relatedCurrencyManagers update their lists.
OnCurrentItemChanged(System.EventArgs.Empty);
}
if (listposition == -1) {
// do not call EndEdit on a row that was not there ( position == -1)
ChangeRecordState(0, false, false, true, false);
}
UpdateIsBinding();
// put the call to OnItemChanged after setting the position, so the
// controls would use the actual position.
// if we have a control bound to a dataView, and then we add a row to a the dataView,
// then the control will use the old listposition to get the data. and this is bad.
//
OnItemChanged(resetEvent);
break;
case System.ComponentModel.ListChangedType.ItemDeleted:
Debug.WriteLineIf(CompModSwitches.DataCursor.TraceVerbose, "System.ComponentModel.ListChangedType.ItemDeleted " + dbe.NewIndex.ToString(CultureInfo.InvariantCulture));
if (dbe.NewIndex == listposition) {
// this means that the current row got deleted.
// cannot end an edit on a row that does not exist anymore
ChangeRecordState(Math.Min(listposition, Count - 1), true, false, true, false);
// put the call to OnItemChanged after setting the position
// in the currencyManager, so controls will use the actual position
OnItemChanged(resetEvent);
break;
}
if (dbe.NewIndex < listposition) {
// this means the current row just moved up by one.
// cannot end an edit on a row that does not exist anymore
ChangeRecordState(listposition - 1, true, false, true, false);
// put the call to OnItemChanged after setting the position
// in the currencyManager, so controls will use the actual position
OnItemChanged(resetEvent);
break;
}
OnItemChanged(resetEvent);
break;
case System.ComponentModel.ListChangedType.ItemChanged:
Debug.WriteLineIf(CompModSwitches.DataCursor.TraceVerbose, "System.ComponentModel.ListChangedType.ItemChanged " + dbe.NewIndex.ToString(CultureInfo.InvariantCulture));
// the current item changed
if (dbe.NewIndex == this.listposition) {
OnCurrentItemChanged(EventArgs.Empty);
}
OnItemChanged(new ItemChangedEventArgs(dbe.NewIndex));
break;
case System.ComponentModel.ListChangedType.ItemMoved:
Debug.WriteLineIf(CompModSwitches.DataCursor.TraceVerbose, "System.ComponentModel.ListChangedType.ItemMoved " + dbe.NewIndex.ToString(CultureInfo.InvariantCulture));
if (dbe.OldIndex == listposition) { // current got moved.
// the position changes, so end the current edit. Make sure there is something that we can end edit...
ChangeRecordState(dbe.NewIndex, true, this.Position > -1 && this.Position < list.Count, true, false);
}
else if (dbe.NewIndex == listposition) { // current was moved
// the position changes, so end the current edit. Make sure there is something that we can end edit
ChangeRecordState(dbe.OldIndex, true, this.Position > -1 && this.Position < list.Count, true, false);
}
OnItemChanged(resetEvent);
break;
case System.ComponentModel.ListChangedType.PropertyDescriptorAdded:
case System.ComponentModel.ListChangedType.PropertyDescriptorDeleted:
case System.ComponentModel.ListChangedType.PropertyDescriptorChanged:
// reset lastGoodKnownRow because it was computed against property descriptors which changed
this.lastGoodKnownRow = -1;
// In Everett, metadata changes did not alter current list position. In Whidbey, this behavior
// preserved - except that we will now force the position to stay in valid range if necessary.
if (listposition == -1 && list.Count > 0)
ChangeRecordState(0, true, false, true, false);
else if (listposition > list.Count - 1)
ChangeRecordState(list.Count - 1, true, false, true, false);
// fire the MetaDataChanged event
OnMetaDataChanged(EventArgs.Empty);
break;
}
// send the ListChanged notification after the position changed in the list
//
OnListChanged(dbe);
} finally {
suspendPushDataInCurrentChanged = false;
}
Debug.Assert(lastGoodKnownRow == -1 || listposition == lastGoodKnownRow, "how did they get out of [....]?");
}
///
/// Causes the CurrentChanged event to occur.
///
internal protected override void OnCurrentChanged(EventArgs e) {
if (!inChangeRecordState) {
Debug.WriteLineIf(CompModSwitches.DataView.TraceVerbose, "OnCurrentChanged() " + e.ToString());
int curLastGoodKnownRow = lastGoodKnownRow;
bool positionChanged = false;
if (!suspendPushDataInCurrentChanged)
positionChanged = CurrencyManager_PushData();
if (Count > 0) {
Object item = list[Position];
if (item is IEditableObject) {
((IEditableObject)item).BeginEdit();
}
}
try {
// if currencyManager changed position then we have two cases:
// 1. the previous lastGoodKnownRow was valid: in that case we fell back so do not fire onCurrentChanged
// 2. the previous lastGoodKnownRow was invalid: we have two cases:
// a. FindGoodRow actually found a good row, so it can't be the one before the user changed the position: fire the onCurrentChanged
// b. FindGoodRow did not find a good row: we should have gotten an exception so we should not even execute this code
if (!positionChanged ||(positionChanged && curLastGoodKnownRow != -1)) {
if (onCurrentChangedHandler != null) {
onCurrentChangedHandler(this, e);
}
// we fire OnCurrentItemChanged event every time we fire the CurrentChanged + when a property of the Current item changed
if (onCurrentItemChangedHandler != null) {
onCurrentItemChangedHandler(this, e);
}
}
}
catch (Exception ex) {
OnDataError(ex);
}
}
}
// this method should only be called when the currency manager receives the ListChangedType.ItemChanged event
// and when the index of the ListChangedEventArgs == the position in the currency manager
///
///
protected virtual void OnItemChanged(ItemChangedEventArgs e) {
// It is possible that CurrencyManager_PushData will change the position
// in the list. in that case we have to fire OnPositionChanged event
bool positionChanged = false;
// We should not push the data when we suspend the changeEvents.
// but we should still fire the OnItemChanged event that we get when processing the EndCurrentEdit method.
if ((e.Index == listposition || (e.Index == -1 && Position < Count)) && !inChangeRecordState)
positionChanged = CurrencyManager_PushData();
Debug.WriteLineIf(CompModSwitches.DataView.TraceVerbose, "OnItemChanged(" + e.Index.ToString(CultureInfo.InvariantCulture) + ") " + e.ToString());
try {
if (onItemChanged != null)
onItemChanged(this, e);
}
catch (Exception ex) {
OnDataError(ex);
}
if (positionChanged)
OnPositionChanged(EventArgs.Empty);
// onItemChangedCalled = true;
}
private void OnListChanged(ListChangedEventArgs e) {
if (onListChanged != null)
onListChanged(this, e);
}
[SuppressMessage("Microsoft.Naming", "CA1702:CompoundWordsShouldBeCasedCorrectly")] //Exists in Everett
internal protected void OnMetaDataChanged(EventArgs e)
{
if (onMetaDataChangedHandler != null)
onMetaDataChangedHandler(this,e);
}
///
///
protected virtual void OnPositionChanged(EventArgs e) {
// if (!inChangeRecordState) {
Debug.WriteLineIf(CompModSwitches.DataView.TraceVerbose, "OnPositionChanged(" + listposition.ToString(CultureInfo.InvariantCulture) + ") " + e.ToString());
try {
if (onPositionChangedHandler != null)
onPositionChangedHandler(this, e);
}
catch (Exception ex) {
OnDataError(ex);
}
// }
}
///
///
/// Forces a repopulation of the CurrencyManager
///
///
public void Refresh() {
if (list.Count > 0 ) {
if (listposition >= list.Count) {
lastGoodKnownRow = -1;
listposition = 0;
}
} else {
listposition = -1;
}
List_ListChanged(list, new System.ComponentModel.ListChangedEventArgs(System.ComponentModel.ListChangedType.Reset, -1));
}
internal void Release() {
UnwireEvents(list);
}
///
/// Resumes binding of component properties to list items.
///
public override void ResumeBinding() {
lastGoodKnownRow = -1;
try {
if (!shouldBind) {
shouldBind = true;
// we need to put the listPosition at the beginning of the list if the list is not empty
this.listposition = (this.list != null && this.list.Count != 0) ? 0:-1;
UpdateIsBinding();
}
}
catch {
shouldBind = false;
UpdateIsBinding();
throw;
}
}
///
/// Suspends binding.
///
public override void SuspendBinding() {
lastGoodKnownRow = -1;
if (shouldBind) {
shouldBind = false;
UpdateIsBinding();
}
}
internal void UnwireEvents(IList list) {
if ((list is IBindingList) && ((IBindingList)list).SupportsChangeNotification) {
((IBindingList)list).ListChanged -= new System.ComponentModel.ListChangedEventHandler(List_ListChanged);
/*
ILiveList liveList = (ILiveList) list;
liveList.TableChanged -= new TableChangedEventHandler(List_TableChanged);
*/
}
}
///
/// [To be supplied.]
///
protected override void UpdateIsBinding() {
UpdateIsBinding(true);
}
private void UpdateIsBinding(bool raiseItemChangedEvent) {
bool newBound = list != null && list.Count > 0 && shouldBind && listposition != -1;
if (list != null)
if (bound != newBound) {
// we will call end edit when moving from bound state to unbounded state
//
//bool endCurrentEdit = bound && !newBound;
bound = newBound;
int newPos = newBound ? 0 : -1;
ChangeRecordState(newPos, bound, (Position != newPos), true, false);
int numLinks = Bindings.Count;
for (int i = 0; i < numLinks; i++) {
Bindings[i].UpdateIsBinding();
}
if (raiseItemChangedEvent) {
OnItemChanged(resetEvent);
}
}
}
private void UpdateLastGoodKnownRow(System.ComponentModel.ListChangedEventArgs e) {
switch (e.ListChangedType) {
case System.ComponentModel.ListChangedType.ItemDeleted:
if (e.NewIndex == lastGoodKnownRow)
lastGoodKnownRow = -1;
break;
case System.ComponentModel.ListChangedType.Reset:
lastGoodKnownRow = -1;
break;
case System.ComponentModel.ListChangedType.ItemAdded:
if (e.NewIndex <= lastGoodKnownRow && lastGoodKnownRow < this.List.Count - 1)
lastGoodKnownRow ++;
break;
case System.ComponentModel.ListChangedType.ItemMoved:
if (e.OldIndex == lastGoodKnownRow)
lastGoodKnownRow = e.NewIndex;
break;
case System.ComponentModel.ListChangedType.ItemChanged:
if (e.NewIndex == lastGoodKnownRow)
lastGoodKnownRow = -1;
break;
}
}
internal void WireEvents(IList list) {
if ((list is IBindingList) && ((IBindingList)list).SupportsChangeNotification) {
((IBindingList)list).ListChanged += new System.ComponentModel.ListChangedEventHandler(List_ListChanged);
/*
ILiveList liveList = (ILiveList) list;
liveList.TableChanged += new TableChangedEventHandler(List_TableChanged);
*/
}
}
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//------------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//-----------------------------------------------------------------------------
namespace System.Windows.Forms {
using System;
using Microsoft.Win32;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.ComponentModel;
using System.Collections;
using System.Reflection;
using System.Globalization;
///
/// Manages the position and bindings of a
/// list.
///
public class CurrencyManager : BindingManagerBase {
private Object dataSource;
private IList list;
private bool bound = false;
private bool shouldBind = true;
///
///
[
SuppressMessage("Microsoft.Design", "CA1051:DoNotDeclareVisibleInstanceFields") // We can't make CurrencyManager.listposition internal
// because it would be a breaking change.
]
protected int listposition = -1;
private int lastGoodKnownRow = -1;
private bool pullingData = false;
private bool inChangeRecordState = false;
private bool suspendPushDataInCurrentChanged = false;
// private bool onItemChangedCalled = false;
// private EventHandler onCurrentChanged;
// private CurrentChangingEventHandler onCurrentChanging;
private ItemChangedEventHandler onItemChanged;
private ListChangedEventHandler onListChanged;
private ItemChangedEventArgs resetEvent = new ItemChangedEventArgs(-1);
private EventHandler onMetaDataChangedHandler;
///
/// Gets the type of the list.
///
protected Type finalType;
///
/// Occurs when the
/// current item has been
/// altered.
///
[SRCategory(SR.CatData)]
public event ItemChangedEventHandler ItemChanged {
add {
onItemChanged += value;
}
remove {
onItemChanged -= value;
}
}
///
///
[
SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors") // If the constructor does not set the dataSource
// it would be a breaking change.
]
internal CurrencyManager(Object dataSource) {
SetDataSource(dataSource);
}
///
/// Gets a value indicating
/// whether items can be added to the list.
///
internal bool AllowAdd {
get {
if (list is IBindingList) {
return ((IBindingList)list).AllowNew;
}
if (list == null)
return false;
return !list.IsReadOnly && !list.IsFixedSize;
}
}
///
/// Gets a value
/// indicating whether edits to the list are allowed.
///
internal bool AllowEdit {
get {
if (list is IBindingList) {
return ((IBindingList)list).AllowEdit;
}
if (list == null)
return false;
return !list.IsReadOnly;
}
}
///
/// Gets a value indicating whether items can be removed from the list.
///
internal bool AllowRemove {
get {
if (list is IBindingList) {
return ((IBindingList)list).AllowRemove;
}
if (list == null)
return false;
return !list.IsReadOnly && !list.IsFixedSize;
}
}
///
/// Gets the number of items in the list.
///
public override int Count {
get {
if (list == null)
return 0;
else
return list.Count;
}
}
///
/// Gets the current item in the list.
///
public override Object Current {
get {
return this[Position];
}
}
internal override Type BindType {
get {
return ListBindingHelper.GetListItemType(this.List);
}
}
///
/// Gets the data source of the list.
///
internal override Object DataSource {
get {
return dataSource;
}
}
internal override void SetDataSource(Object dataSource) {
if (this.dataSource != dataSource) {
Release();
this.dataSource = dataSource;
this.list = null;
this.finalType = null;
Object tempList = dataSource;
if (tempList is Array) {
finalType = tempList.GetType();
tempList = (Array)tempList;
}
if (tempList is IListSource) {
tempList = ((IListSource)tempList).GetList();
}
if (tempList is IList) {
if (finalType == null) {
finalType = tempList.GetType();
}
this.list = (IList)tempList;
WireEvents(list);
if (list.Count > 0 )
listposition = 0;
else
listposition = -1;
OnItemChanged(resetEvent);
OnListChanged(new ListChangedEventArgs(ListChangedType.Reset, -1, -1));
UpdateIsBinding();
}
else {
if (tempList == null) {
throw new ArgumentNullException("dataSource");
}
throw new ArgumentException(SR.GetString(SR.ListManagerSetDataSource, tempList.GetType().FullName), "dataSource");
}
}
}
///
/// Gets a value indicating whether the list is bound to a data source.
///
internal override bool IsBinding {
get {
return bound;
}
}
// The DataGridView needs this.
internal bool ShouldBind {
get {
return shouldBind;
}
}
///
/// Gets the list as an object.
///
public IList List {
get {
// NOTE: do not change this to throw an exception if the list is not IBindingList.
// doing this will cause a major performance hit when wiring the
// dataGrid to listen for MetaDataChanged events from the IBindingList
// (basically we would have to wrap all calls to CurrencyManager::List with
// a try/catch block.)
//
return list;
}
}
///
/// Gets or sets the position you are at within the list.
///
public override int Position {
get {
return listposition;
}
set {
if (listposition == -1)
return;
if (value < 0)
value = 0;
int count = list.Count;
if (value >= count)
value = count - 1;
ChangeRecordState(value, listposition != value, true, true, false); // true for endCurrentEdit
// true for firingPositionChange notification
// data will be pulled from controls anyway.
}
}
///
/// Gets or sets the object at the specified index.
///
internal Object this[int index] {
get {
if (index < 0 || index >= list.Count) {
throw new IndexOutOfRangeException(SR.GetString(SR.ListManagerNoValue, index.ToString(CultureInfo.CurrentCulture)));
}
return list[index];
}
set {
if (index < 0 || index >= list.Count) {
throw new IndexOutOfRangeException(SR.GetString(SR.ListManagerNoValue, index.ToString(CultureInfo.CurrentCulture)));
}
list[index] = value;
}
}
///
/// [To be supplied.]
///
public override void AddNew() {
IBindingList ibl = list as IBindingList;
if (ibl != null) {
ibl.AddNew();
}
else {
// If the list is not IBindingList, then throw an exception:
throw new NotSupportedException(SR.GetString(SR.CurrencyManagerCantAddNew));
}
ChangeRecordState(list.Count - 1, (Position != list.Count - 1), (Position != list.Count - 1), true, true); // true for firingPositionChangeNotification
// true for pulling data from the controls
}
///
/// Cancels the current edit operation.
///
public override void CancelCurrentEdit() {
if (Count > 0) {
Object item = (Position >= 0 && Position < list.Count) ? list[Position] : null;
// onItemChangedCalled = false;
IEditableObject iEditableItem = item as IEditableObject;
if (iEditableItem != null) {
iEditableItem.CancelEdit();
}
ICancelAddNew iListWithCancelAddNewSupport = list as ICancelAddNew;
if (iListWithCancelAddNewSupport != null) {
iListWithCancelAddNewSupport.CancelNew(this.Position);
}
OnItemChanged(new ItemChangedEventArgs(Position));
if (this.Position != -1) {
OnListChanged(new ListChangedEventArgs(ListChangedType.ItemChanged, this.Position));
}
}
}
private void ChangeRecordState(int newPosition, bool validating, bool endCurrentEdit, bool firePositionChange, bool pullData) {
if (newPosition == -1 && list.Count == 0) {
if (listposition != -1) {
this.listposition = -1;
OnPositionChanged(EventArgs.Empty);
}
return;
}
if ((newPosition < 0 || newPosition >= Count) && this.IsBinding) {
throw new IndexOutOfRangeException(SR.GetString(SR.ListManagerBadPosition));
}
// if PushData fails in the OnCurrentChanged and there was a lastGoodKnownRow
// then the position does not change, so we should not fire the OnPositionChanged
// event;
// this is why we have to cache the old position and compare that w/ the position that
// the user will want to navigate to
int oldPosition = listposition;
if (endCurrentEdit) {
// Do not PushData when pro. See ASURT 65095.
inChangeRecordState = true;
try {
EndCurrentEdit();
} finally {
inChangeRecordState = false;
}
}
// we pull the data from the controls only when the ListManager changes the list. when the backEnd changes the list we do not
// pull the data from the controls
if (validating && pullData) {
CurrencyManager_PullData();
}
// vsWhidbey 425961: EndCurrentEdit or PullData can cause the list managed by the CurrencyManager to shrink.
this.listposition = Math.Min(newPosition, Count - 1);
if (validating) {
OnCurrentChanged(EventArgs.Empty);
}
bool positionChanging = (oldPosition != listposition);
if (positionChanging && firePositionChange) {
OnPositionChanged(EventArgs.Empty);
}
}
///
/// Throws an exception if there is no list.
///
protected void CheckEmpty() {
if (dataSource == null || list == null || list.Count == 0) {
throw new InvalidOperationException(SR.GetString(SR.ListManagerEmptyList));
}
}
// will return true if this function changes the position in the list
private bool CurrencyManager_PushData() {
if (pullingData)
return false;
int initialPosition = listposition;
if (lastGoodKnownRow == -1) {
try {
PushData();
}
catch (Exception ex) {
OnDataError(ex);
// get the first item in the list that is good to push data
// for now, we assume that there is a row in the backEnd
// that is good for all the bindings.
FindGoodRow();
}
lastGoodKnownRow = listposition;
} else {
try {
PushData();
}
catch (Exception ex) {
OnDataError(ex);
listposition = lastGoodKnownRow;
PushData();
}
lastGoodKnownRow = listposition;
}
return initialPosition != listposition;
}
private bool CurrencyManager_PullData() {
bool success = true;
pullingData = true;
try {
PullData(out success);
} finally {
pullingData = false;
}
return success;
}
///
/// [To be supplied.]
///
public override void RemoveAt(int index) {
list.RemoveAt(index);
}
///
/// Ends the current edit operation.
///
public override void EndCurrentEdit() {
if (Count > 0) {
bool success = CurrencyManager_PullData();
if (success) {
Object item = (Position >= 0 && Position < list.Count) ? list[Position] : null;
IEditableObject iEditableItem = item as IEditableObject;
if (iEditableItem != null) {
iEditableItem.EndEdit();
}
ICancelAddNew iListWithCancelAddNewSupport = list as ICancelAddNew;
if (iListWithCancelAddNewSupport != null) {
iListWithCancelAddNewSupport.EndNew(this.Position);
}
}
}
}
private void FindGoodRow() {
int rowCount = this.list.Count;
for (int i = 0; i < rowCount; i++) {
listposition = i;
try {
PushData();
}
catch (Exception ex) {
OnDataError(ex);
continue;
}
listposition = i;
return;
}
// if we got here, the list did not contain any rows suitable for the bindings
// suspend binding and throw an exception
SuspendBinding();
throw new InvalidOperationException(SR.GetString(SR.DataBindingPushDataException));
}
///
/// Sets the column to sort by, and the direction of the sort.
///
internal void SetSort(PropertyDescriptor property, ListSortDirection sortDirection) {
if (list is IBindingList && ((IBindingList)list).SupportsSorting) {
((IBindingList)list).ApplySort(property, sortDirection);
}
}
///
/// Gets a
///
internal PropertyDescriptor GetSortProperty() {
if ((list is IBindingList) && ((IBindingList)list).SupportsSorting) {
return ((IBindingList)list).SortProperty;
}
return null;
}
///
/// Gets the sort direction of a list.
///
internal ListSortDirection GetSortDirection() {
if ((list is IBindingList) && ((IBindingList)list).SupportsSorting) {
return ((IBindingList)list).SortDirection;
}
return ListSortDirection.Ascending;
}
///
/// Find the position of a desired list item.
///
internal int Find(PropertyDescriptor property, Object key, bool keepIndex) {
if (key == null)
throw new ArgumentNullException("key");
if (property != null && (list is IBindingList) && ((IBindingList)list).SupportsSearching) {
return ((IBindingList)list).Find(property, key);
}
for (int i = 0; i < list.Count; i++) {
object value = property.GetValue(list[i]);
if (key.Equals(value)) {
return i;
}
}
return -1;
}
///
/// Gets the name of the list.
///
internal override string GetListName() {
if (list is ITypedList) {
return ((ITypedList)list).GetListName(null);
}
else {
return finalType.Name;
}
}
///
/// Gets the name of the specified list.
///
protected internal override string GetListName(ArrayList listAccessors) {
if (list is ITypedList) {
PropertyDescriptor[] properties = new PropertyDescriptor[listAccessors.Count];
listAccessors.CopyTo(properties, 0);
return ((ITypedList)list).GetListName(properties);
}
return "";
}
///
///
internal override PropertyDescriptorCollection GetItemProperties(PropertyDescriptor[] listAccessors) {
return ListBindingHelper.GetListItemProperties(this.list, listAccessors);
}
///
/// Gets the
///
public override PropertyDescriptorCollection GetItemProperties() {
return GetItemProperties(null);
}
///
/// Gets the
///
private void List_ListChanged(Object sender, System.ComponentModel.ListChangedEventArgs e) {
// If you change the assert below, better change the
// code in the OnCurrentChanged that deals w/ firing the OnCurrentChanged event
Debug.Assert(lastGoodKnownRow == -1 || lastGoodKnownRow == listposition, "if we have a valid lastGoodKnownRow, then it should equal the position in the list");
// bug 139627: when the data view fires an ItemMoved event where the old position is negative, that really means
// that a row was added
// bug 156236: when the data view fires an ItemMoved event where the new position is negative, that really means
// that a row was deleted
// dbe is our DataBindingEvent
//
ListChangedEventArgs dbe;
if (e.ListChangedType == ListChangedType.ItemMoved && e.OldIndex < 0) {
dbe = new ListChangedEventArgs(ListChangedType.ItemAdded, e.NewIndex, e.OldIndex);
} else if (e.ListChangedType == ListChangedType.ItemMoved && e.NewIndex < 0) {
dbe = new ListChangedEventArgs(ListChangedType.ItemDeleted, e.OldIndex, e.NewIndex);
} else {
dbe = e;
}
int oldposition = listposition;
UpdateLastGoodKnownRow(dbe);
UpdateIsBinding();
if (list.Count == 0) {
listposition = -1;
if (oldposition != -1) {
// if we used to have a current row, but not any more, then report current as changed
OnPositionChanged(EventArgs.Empty);
OnCurrentChanged(EventArgs.Empty);
}
if (dbe.ListChangedType == System.ComponentModel.ListChangedType.Reset && e.NewIndex == -1) {
// if the list is reset, then let our users know about it.
OnItemChanged(resetEvent);
}
if (dbe.ListChangedType == System.ComponentModel.ListChangedType.ItemDeleted) {
// if the list is reset, then let our users know about it.
OnItemChanged(resetEvent);
}
// we should still fire meta data change notification even when the list is empty
if (e.ListChangedType == System.ComponentModel.ListChangedType.PropertyDescriptorAdded ||
e.ListChangedType == System.ComponentModel.ListChangedType.PropertyDescriptorDeleted ||
e.ListChangedType == System.ComponentModel.ListChangedType.PropertyDescriptorChanged)
OnMetaDataChanged(EventArgs.Empty);
//
OnListChanged(dbe);
return;
}
suspendPushDataInCurrentChanged = true;
try {
switch (dbe.ListChangedType) {
case System.ComponentModel.ListChangedType.Reset:
Debug.WriteLineIf(CompModSwitches.DataCursor.TraceVerbose, "System.ComponentModel.ListChangedType.Reset Position: " + Position + " Count: " + list.Count);
if (listposition == -1 && list.Count > 0)
ChangeRecordState(0, true, false, true, false); // last false: we don't pull the data from the control when DM changes
else
ChangeRecordState(Math.Min(listposition,list.Count - 1), true, false, true, false);
UpdateIsBinding(/*raiseItemChangedEvent:*/ false);
OnItemChanged(resetEvent);
break;
case System.ComponentModel.ListChangedType.ItemAdded:
Debug.WriteLineIf(CompModSwitches.DataCursor.TraceVerbose, "System.ComponentModel.ListChangedType.ItemAdded " + dbe.NewIndex.ToString(CultureInfo.InvariantCulture));
if (dbe.NewIndex <= listposition && listposition < list.Count - 1) {
// this means the current row just moved down by one.
// the position changes, so end the current edit
ChangeRecordState(listposition + 1, true, true, listposition != list.Count - 2, false);
UpdateIsBinding();
// 85426: refresh the list after we got the item added event
OnItemChanged(resetEvent);
// 84460: when we get the itemAdded, and the position was at the end
// of the list, do the right thing and notify the positionChanged after refreshing the list
if (listposition == list.Count - 1)
OnPositionChanged(EventArgs.Empty);
break;
} else if (dbe.NewIndex == this.listposition && this.listposition == list.Count - 1 && this.listposition != -1) {
// The CurrencyManager has a non-empty list.
// The position inside the currency manager is at the end of the list and the list still fired an ItemAdded event.
// This could be the second ItemAdded event that the DataView fires to signal that the AddNew operation was commited.
// We need to fire CurrentItemChanged event so that relatedCurrencyManagers update their lists.
OnCurrentItemChanged(System.EventArgs.Empty);
}
if (listposition == -1) {
// do not call EndEdit on a row that was not there ( position == -1)
ChangeRecordState(0, false, false, true, false);
}
UpdateIsBinding();
// put the call to OnItemChanged after setting the position, so the
// controls would use the actual position.
// if we have a control bound to a dataView, and then we add a row to a the dataView,
// then the control will use the old listposition to get the data. and this is bad.
//
OnItemChanged(resetEvent);
break;
case System.ComponentModel.ListChangedType.ItemDeleted:
Debug.WriteLineIf(CompModSwitches.DataCursor.TraceVerbose, "System.ComponentModel.ListChangedType.ItemDeleted " + dbe.NewIndex.ToString(CultureInfo.InvariantCulture));
if (dbe.NewIndex == listposition) {
// this means that the current row got deleted.
// cannot end an edit on a row that does not exist anymore
ChangeRecordState(Math.Min(listposition, Count - 1), true, false, true, false);
// put the call to OnItemChanged after setting the position
// in the currencyManager, so controls will use the actual position
OnItemChanged(resetEvent);
break;
}
if (dbe.NewIndex < listposition) {
// this means the current row just moved up by one.
// cannot end an edit on a row that does not exist anymore
ChangeRecordState(listposition - 1, true, false, true, false);
// put the call to OnItemChanged after setting the position
// in the currencyManager, so controls will use the actual position
OnItemChanged(resetEvent);
break;
}
OnItemChanged(resetEvent);
break;
case System.ComponentModel.ListChangedType.ItemChanged:
Debug.WriteLineIf(CompModSwitches.DataCursor.TraceVerbose, "System.ComponentModel.ListChangedType.ItemChanged " + dbe.NewIndex.ToString(CultureInfo.InvariantCulture));
// the current item changed
if (dbe.NewIndex == this.listposition) {
OnCurrentItemChanged(EventArgs.Empty);
}
OnItemChanged(new ItemChangedEventArgs(dbe.NewIndex));
break;
case System.ComponentModel.ListChangedType.ItemMoved:
Debug.WriteLineIf(CompModSwitches.DataCursor.TraceVerbose, "System.ComponentModel.ListChangedType.ItemMoved " + dbe.NewIndex.ToString(CultureInfo.InvariantCulture));
if (dbe.OldIndex == listposition) { // current got moved.
// the position changes, so end the current edit. Make sure there is something that we can end edit...
ChangeRecordState(dbe.NewIndex, true, this.Position > -1 && this.Position < list.Count, true, false);
}
else if (dbe.NewIndex == listposition) { // current was moved
// the position changes, so end the current edit. Make sure there is something that we can end edit
ChangeRecordState(dbe.OldIndex, true, this.Position > -1 && this.Position < list.Count, true, false);
}
OnItemChanged(resetEvent);
break;
case System.ComponentModel.ListChangedType.PropertyDescriptorAdded:
case System.ComponentModel.ListChangedType.PropertyDescriptorDeleted:
case System.ComponentModel.ListChangedType.PropertyDescriptorChanged:
// reset lastGoodKnownRow because it was computed against property descriptors which changed
this.lastGoodKnownRow = -1;
// In Everett, metadata changes did not alter current list position. In Whidbey, this behavior
// preserved - except that we will now force the position to stay in valid range if necessary.
if (listposition == -1 && list.Count > 0)
ChangeRecordState(0, true, false, true, false);
else if (listposition > list.Count - 1)
ChangeRecordState(list.Count - 1, true, false, true, false);
// fire the MetaDataChanged event
OnMetaDataChanged(EventArgs.Empty);
break;
}
// send the ListChanged notification after the position changed in the list
//
OnListChanged(dbe);
} finally {
suspendPushDataInCurrentChanged = false;
}
Debug.Assert(lastGoodKnownRow == -1 || listposition == lastGoodKnownRow, "how did they get out of [....]?");
}
///
/// Causes the CurrentChanged event to occur.
///
internal protected override void OnCurrentChanged(EventArgs e) {
if (!inChangeRecordState) {
Debug.WriteLineIf(CompModSwitches.DataView.TraceVerbose, "OnCurrentChanged() " + e.ToString());
int curLastGoodKnownRow = lastGoodKnownRow;
bool positionChanged = false;
if (!suspendPushDataInCurrentChanged)
positionChanged = CurrencyManager_PushData();
if (Count > 0) {
Object item = list[Position];
if (item is IEditableObject) {
((IEditableObject)item).BeginEdit();
}
}
try {
// if currencyManager changed position then we have two cases:
// 1. the previous lastGoodKnownRow was valid: in that case we fell back so do not fire onCurrentChanged
// 2. the previous lastGoodKnownRow was invalid: we have two cases:
// a. FindGoodRow actually found a good row, so it can't be the one before the user changed the position: fire the onCurrentChanged
// b. FindGoodRow did not find a good row: we should have gotten an exception so we should not even execute this code
if (!positionChanged ||(positionChanged && curLastGoodKnownRow != -1)) {
if (onCurrentChangedHandler != null) {
onCurrentChangedHandler(this, e);
}
// we fire OnCurrentItemChanged event every time we fire the CurrentChanged + when a property of the Current item changed
if (onCurrentItemChangedHandler != null) {
onCurrentItemChangedHandler(this, e);
}
}
}
catch (Exception ex) {
OnDataError(ex);
}
}
}
// this method should only be called when the currency manager receives the ListChangedType.ItemChanged event
// and when the index of the ListChangedEventArgs == the position in the currency manager
///
///
protected virtual void OnItemChanged(ItemChangedEventArgs e) {
// It is possible that CurrencyManager_PushData will change the position
// in the list. in that case we have to fire OnPositionChanged event
bool positionChanged = false;
// We should not push the data when we suspend the changeEvents.
// but we should still fire the OnItemChanged event that we get when processing the EndCurrentEdit method.
if ((e.Index == listposition || (e.Index == -1 && Position < Count)) && !inChangeRecordState)
positionChanged = CurrencyManager_PushData();
Debug.WriteLineIf(CompModSwitches.DataView.TraceVerbose, "OnItemChanged(" + e.Index.ToString(CultureInfo.InvariantCulture) + ") " + e.ToString());
try {
if (onItemChanged != null)
onItemChanged(this, e);
}
catch (Exception ex) {
OnDataError(ex);
}
if (positionChanged)
OnPositionChanged(EventArgs.Empty);
// onItemChangedCalled = true;
}
private void OnListChanged(ListChangedEventArgs e) {
if (onListChanged != null)
onListChanged(this, e);
}
[SuppressMessage("Microsoft.Naming", "CA1702:CompoundWordsShouldBeCasedCorrectly")] //Exists in Everett
internal protected void OnMetaDataChanged(EventArgs e)
{
if (onMetaDataChangedHandler != null)
onMetaDataChangedHandler(this,e);
}
///
///
protected virtual void OnPositionChanged(EventArgs e) {
// if (!inChangeRecordState) {
Debug.WriteLineIf(CompModSwitches.DataView.TraceVerbose, "OnPositionChanged(" + listposition.ToString(CultureInfo.InvariantCulture) + ") " + e.ToString());
try {
if (onPositionChangedHandler != null)
onPositionChangedHandler(this, e);
}
catch (Exception ex) {
OnDataError(ex);
}
// }
}
///
///
/// Forces a repopulation of the CurrencyManager
///
///
public void Refresh() {
if (list.Count > 0 ) {
if (listposition >= list.Count) {
lastGoodKnownRow = -1;
listposition = 0;
}
} else {
listposition = -1;
}
List_ListChanged(list, new System.ComponentModel.ListChangedEventArgs(System.ComponentModel.ListChangedType.Reset, -1));
}
internal void Release() {
UnwireEvents(list);
}
///
/// Resumes binding of component properties to list items.
///
public override void ResumeBinding() {
lastGoodKnownRow = -1;
try {
if (!shouldBind) {
shouldBind = true;
// we need to put the listPosition at the beginning of the list if the list is not empty
this.listposition = (this.list != null && this.list.Count != 0) ? 0:-1;
UpdateIsBinding();
}
}
catch {
shouldBind = false;
UpdateIsBinding();
throw;
}
}
///
/// Suspends binding.
///
public override void SuspendBinding() {
lastGoodKnownRow = -1;
if (shouldBind) {
shouldBind = false;
UpdateIsBinding();
}
}
internal void UnwireEvents(IList list) {
if ((list is IBindingList) && ((IBindingList)list).SupportsChangeNotification) {
((IBindingList)list).ListChanged -= new System.ComponentModel.ListChangedEventHandler(List_ListChanged);
/*
ILiveList liveList = (ILiveList) list;
liveList.TableChanged -= new TableChangedEventHandler(List_TableChanged);
*/
}
}
///
/// [To be supplied.]
///
protected override void UpdateIsBinding() {
UpdateIsBinding(true);
}
private void UpdateIsBinding(bool raiseItemChangedEvent) {
bool newBound = list != null && list.Count > 0 && shouldBind && listposition != -1;
if (list != null)
if (bound != newBound) {
// we will call end edit when moving from bound state to unbounded state
//
//bool endCurrentEdit = bound && !newBound;
bound = newBound;
int newPos = newBound ? 0 : -1;
ChangeRecordState(newPos, bound, (Position != newPos), true, false);
int numLinks = Bindings.Count;
for (int i = 0; i < numLinks; i++) {
Bindings[i].UpdateIsBinding();
}
if (raiseItemChangedEvent) {
OnItemChanged(resetEvent);
}
}
}
private void UpdateLastGoodKnownRow(System.ComponentModel.ListChangedEventArgs e) {
switch (e.ListChangedType) {
case System.ComponentModel.ListChangedType.ItemDeleted:
if (e.NewIndex == lastGoodKnownRow)
lastGoodKnownRow = -1;
break;
case System.ComponentModel.ListChangedType.Reset:
lastGoodKnownRow = -1;
break;
case System.ComponentModel.ListChangedType.ItemAdded:
if (e.NewIndex <= lastGoodKnownRow && lastGoodKnownRow < this.List.Count - 1)
lastGoodKnownRow ++;
break;
case System.ComponentModel.ListChangedType.ItemMoved:
if (e.OldIndex == lastGoodKnownRow)
lastGoodKnownRow = e.NewIndex;
break;
case System.ComponentModel.ListChangedType.ItemChanged:
if (e.NewIndex == lastGoodKnownRow)
lastGoodKnownRow = -1;
break;
}
}
internal void WireEvents(IList list) {
if ((list is IBindingList) && ((IBindingList)list).SupportsChangeNotification) {
((IBindingList)list).ListChanged += new System.ComponentModel.ListChangedEventHandler(List_ListChanged);
/*
ILiveList liveList = (ILiveList) list;
liveList.TableChanged += new TableChangedEventHandler(List_TableChanged);
*/
}
}
}
}
// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- SignedPkcs7.cs
- ConfigurationLockCollection.cs
- FontFamilyValueSerializer.cs
- EventBindingService.cs
- Stroke.cs
- DataRecordInternal.cs
- OuterGlowBitmapEffect.cs
- SerialPinChanges.cs
- DecoderNLS.cs
- ElementUtil.cs
- XmlArrayAttribute.cs
- HijriCalendar.cs
- Helper.cs
- SafeFindHandle.cs
- SelectionRangeConverter.cs
- Queue.cs
- SqlMetaData.cs
- InvokerUtil.cs
- RoleServiceManager.cs
- ExpressionWriter.cs
- ConfigurationSchemaErrors.cs
- ExtendedProperty.cs
- DataGridViewCheckBoxColumn.cs
- BindingGraph.cs
- GenericIdentity.cs
- wgx_render.cs
- PolyBezierSegment.cs
- WmlSelectionListAdapter.cs
- ManagedCodeMarkers.cs
- ObjectViewEntityCollectionData.cs
- FloaterParaClient.cs
- SqlUserDefinedAggregateAttribute.cs
- WindowsListBox.cs
- XmlnsCache.cs
- KeyMatchBuilder.cs
- Decorator.cs
- Win32MouseDevice.cs
- dataSvcMapFileLoader.cs
- _ChunkParse.cs
- FillRuleValidation.cs
- SqlMetaData.cs
- Underline.cs
- baseshape.cs
- DrawListViewSubItemEventArgs.cs
- KeyNotFoundException.cs
- WhiteSpaceTrimStringConverter.cs
- DataViewManagerListItemTypeDescriptor.cs
- DBSchemaRow.cs
- GridView.cs
- PropertyValueUIItem.cs
- XmlReflectionMember.cs
- ValuePattern.cs
- Int32Animation.cs
- SingleKeyFrameCollection.cs
- EventLogWatcher.cs
- DataGridViewTopRowAccessibleObject.cs
- XmlILStorageConverter.cs
- ConsoleTraceListener.cs
- PackWebRequest.cs
- ExpressionCopier.cs
- SchemaNotation.cs
- PrintDialogException.cs
- DataGridViewSelectedRowCollection.cs
- SymDocumentType.cs
- ApplicationSettingsBase.cs
- bidPrivateBase.cs
- XsdCachingReader.cs
- ToolStripOverflow.cs
- ContextActivityUtils.cs
- StringReader.cs
- CngKeyCreationParameters.cs
- HtmlInputImage.cs
- XPathDocumentBuilder.cs
- FileAccessException.cs
- FaultConverter.cs
- JavascriptCallbackBehaviorAttribute.cs
- ScriptRef.cs
- ZoneButton.cs
- TcpProcessProtocolHandler.cs
- BaseWebProxyFinder.cs
- MeasureItemEvent.cs
- TraceContextRecord.cs
- RequestTimeoutManager.cs
- StatusBar.cs
- SQLMoney.cs
- GetPageNumberCompletedEventArgs.cs
- SoapIgnoreAttribute.cs
- WSSecureConversationDec2005.cs
- KeyedPriorityQueue.cs
- ResponseBodyWriter.cs
- KeyValuePair.cs
- IFlowDocumentViewer.cs
- PropertyGrid.cs
- ActivityLocationReferenceEnvironment.cs
- MarkupCompiler.cs
- SmtpReplyReaderFactory.cs
- BaseCollection.cs
- _emptywebproxy.cs
- SystemResourceKey.cs
- TypeReference.cs