/// <summary>
/// Construct a NotifyCollectionChangedEventArgs that describes a multi-item change (or a reset).
/// </summary>
/// <param name="action">The action that caused the event.</param>
/// <param name="changedItems">The items affected by the change.</param>
/// <param name="startingIndex">The index where the change occurred.</param>
public MVVMNotifyCollectionChangedEventArgs(MVVMNotifyCollectionChangedAction action, IList changedItems, int startingIndex)
{
if ((action != MVVMNotifyCollectionChangedAction.Add) && (action != MVVMNotifyCollectionChangedAction.Remove) &&
(action != MVVMNotifyCollectionChangedAction.Reset))
{
throw new Exception("action");
}
if (action == MVVMNotifyCollectionChangedAction.Reset)
{
if (changedItems != null)
{
throw new Exception("action");
}
if (startingIndex != -1)
{
throw new Exception("action");
}
InitializeAdd(action, null, -1);
}
else
{
if (changedItems == null)
{
throw new Exception("action");
}
if (startingIndex < -1)
{
throw new Exception("action");
}
InitializeAddOrRemove(action, changedItems, startingIndex);
}
}
/// <summary>
/// Construct a NotifyCollectionChangedEventArgs that describes a one-item change.
/// </summary>
/// <param name="action">The action that caused the event.</param>
/// <param name="changedItem">The item affected by the change.</param>
/// <param name="index">The index where the change occurred.</param>
public MVVMNotifyCollectionChangedEventArgs(MVVMNotifyCollectionChangedAction action, object changedItem, int index)
{
if ((action != MVVMNotifyCollectionChangedAction.Add) && (action != MVVMNotifyCollectionChangedAction.Remove) &&
(action != MVVMNotifyCollectionChangedAction.Reset))
{
throw new Exception("action");
}
if (action == MVVMNotifyCollectionChangedAction.Reset)
{
if (changedItem != null)
{
throw new Exception("action");
}
if (index != -1)
{
throw new Exception("action");
}
InitializeAdd(action, null, -1);
}
else
{
InitializeAddOrRemove(action, new object[] { changedItem }, index);
}
}
/// <summary>
/// Construct a NotifyCollectionChangedEventArgs that describes a multi-item change.
/// </summary>
/// <param name="action">The action that caused the event.</param>
/// <param name="changedItems">The items affected by the change.</param>
public MVVMNotifyCollectionChangedEventArgs(MVVMNotifyCollectionChangedAction action, IList changedItems)
{
if ((action != MVVMNotifyCollectionChangedAction.Add) && (action != MVVMNotifyCollectionChangedAction.Remove) &&
(action != MVVMNotifyCollectionChangedAction.Reset))
{
throw new Exception("action");
}
if (action == MVVMNotifyCollectionChangedAction.Reset)
{
if (changedItems != null)
{
throw new Exception("action");
}
InitializeAdd(action, null, -1);
}
else
{
if (changedItems == null)
{
throw new ArgumentNullException("changedItems");
}
InitializeAddOrRemove(action, changedItems, -1);
}
}
/// <summary>
/// Construct a NotifyCollectionChangedEventArgs that describes a one-item Replace event.
/// </summary>
/// <param name="action">Can only be a Replace action.</param>
/// <param name="newItem">The new item replacing the original item.</param>
/// <param name="oldItem">The original item that is replaced.</param>
public MVVMNotifyCollectionChangedEventArgs(MVVMNotifyCollectionChangedAction action, object newItem, object oldItem)
{
if (action != MVVMNotifyCollectionChangedAction.Replace)
{
throw new Exception("action");
}
InitializeMoveOrReplace(action, new object[] { newItem }, new object[] { oldItem }, -1, -1);
}
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
/// <summary>
/// Construct a NotifyCollectionChangedEventArgs that describes a reset change.
/// </summary>
/// <param name="action">The action that caused the event (must be Reset).</param>
public MVVMNotifyCollectionChangedEventArgs(MVVMNotifyCollectionChangedAction action)
{
if (action != MVVMNotifyCollectionChangedAction.Reset)
{
throw new Exception("action");
}
InitializeAdd(action, null, -1);
}
/// <summary>
/// Construct a NotifyCollectionChangedEventArgs that describes a multi-item Move event.
/// </summary>
/// <param name="action">The action that caused the event.</param>
/// <param name="changedItems">The items affected by the change.</param>
/// <param name="index">The new index for the changed items.</param>
/// <param name="oldIndex">The old index for the changed items.</param>
public MVVMNotifyCollectionChangedEventArgs(MVVMNotifyCollectionChangedAction action, IList changedItems, int index, int oldIndex)
{
if (action != MVVMNotifyCollectionChangedAction.Move)
{
throw new Exception("action");
}
if (index < 0)
{
throw new Exception("action");
}
InitializeMoveOrReplace(action, changedItems, changedItems, index, oldIndex);
}
private void InitializeAdd(MVVMNotifyCollectionChangedAction action, IList newItems, int newStartingIndex)
{
_action = action;
#if FEATURE_LEGACYNETCF
if (CompatibilitySwitches.IsAppEarlierThanWindowsPhone8)
{
_newItems = newItems;
}
else
#endif // !FEATURE_LEGACYNETCF
{
_newItems = (newItems == null) ? null : ArrayList.ReadOnly(newItems);
}
_newStartingIndex = newStartingIndex;
}
private void InitializeAddOrRemove(MVVMNotifyCollectionChangedAction action, IList changedItems, int startingIndex)
{
if (action == MVVMNotifyCollectionChangedAction.Add)
{
InitializeAdd(action, changedItems, startingIndex);
}
else if (action == MVVMNotifyCollectionChangedAction.Remove)
{
InitializeRemove(action, changedItems, startingIndex);
}
else
{
//Contract.Assert (false, String.Format ("Unsupported action: {0}", action.ToString ()));
}
}
/// <summary>
/// Construct a NotifyCollectionChangedEventArgs with given fields (no validation). Used by WinRT marshaling.
/// </summary>
internal MVVMNotifyCollectionChangedEventArgs(MVVMNotifyCollectionChangedAction action, IList newItems, IList oldItems, int newIndex, int oldIndex)
{
_action = action;
#if FEATURE_LEGACYNETCF
if (CompatibilitySwitches.IsAppEarlierThanWindowsPhone8)
{
_newItems = newItems;
}
else
#endif
{
_newItems = (newItems == null) ? null : ArrayList.ReadOnly(newItems);
}
_oldItems = (oldItems == null) ? null : ArrayList.ReadOnly(oldItems);
_newStartingIndex = newIndex;
_oldStartingIndex = oldIndex;
}
/// <summary>
/// Construct a NotifyCollectionChangedEventArgs that describes a multi-item Replace event.
/// </summary>
/// <param name="action">Can only be a Replace action.</param>
/// <param name="newItems">The new items replacing the original items.</param>
/// <param name="oldItems">The original items that are replaced.</param>
/// <param name="startingIndex">The starting index of the items being replaced.</param>
public MVVMNotifyCollectionChangedEventArgs(MVVMNotifyCollectionChangedAction action, IList newItems, IList oldItems, int startingIndex)
{
if (action != MVVMNotifyCollectionChangedAction.Replace)
{
throw new Exception("action");
}
if (newItems == null)
{
throw new ArgumentNullException("newItems");
}
if (oldItems == null)
{
throw new ArgumentNullException("oldItems");
}
InitializeMoveOrReplace(action, newItems, oldItems, startingIndex, startingIndex);
}
/// <summary>
/// Construct a NotifyCollectionChangedEventArgs that describes a one-item Replace event.
/// </summary>
/// <param name="action">Can only be a Replace action.</param>
/// <param name="newItem">The new item replacing the original item.</param>
/// <param name="oldItem">The original item that is replaced.</param>
/// <param name="index">The index of the item being replaced.</param>
public MVVMNotifyCollectionChangedEventArgs(MVVMNotifyCollectionChangedAction action, object newItem, object oldItem, int index)
{
if (action != MVVMNotifyCollectionChangedAction.Replace)
{
throw new Exception("action");
}
int oldStartingIndex = index;
#if FEATURE_LEGACYNETCF
if (CompatibilitySwitches.IsAppEarlierThanWindowsPhone8)
{
// Dev11 444113 quirk:
// This is a "Replace" so the old and new index should both be set to the index passed in however
// NetCF on Mango incorrectly leaves OldStartingIndex at -1 and Mango apps depend on this behavior.
oldStartingIndex = -1;
}
#endif
InitializeMoveOrReplace(action, new object[] { newItem }, new object[] { oldItem }, index, oldStartingIndex);
}
/// <summary>
/// Helper to raise CollectionChanged event to any listeners
/// </summary>
private void OnCollectionChanged(MVVMNotifyCollectionChangedAction action, object oldItem, object newItem, int index)
{
OnCollectionChanged(new MVVMNotifyCollectionChangedEventArgs(action, newItem, oldItem, index));
}
private void InitializeMoveOrReplace(MVVMNotifyCollectionChangedAction action, IList newItems, IList oldItems, int startingIndex, int oldStartingIndex)
{
InitializeAdd(action, newItems, startingIndex);
InitializeRemove(action, oldItems, oldStartingIndex);
}
private void InitializeRemove(MVVMNotifyCollectionChangedAction action, IList oldItems, int oldStartingIndex)
{
_action = action;
_oldItems = (oldItems == null) ? null : ArrayList.ReadOnly(oldItems);
_oldStartingIndex = oldStartingIndex;
}
