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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
using System.Windows.Input;
using System.Windows.Controls;
namespace MS.Internal.Ink
{
/// <summary>
/// IStylusEditing Interface
/// </summary>
internal interface IStylusEditing
{
/// <summary>
/// AddStylusPoints
/// </summary>
/// <param name="stylusPoints">stylusPoints</param>
/// <param name="userInitiated">only true if eventArgs.UserInitiated is true</param>
void AddStylusPoints(StylusPointCollection stylusPoints, bool userInitiated);
}
/// <summary>
/// StylusEditingBehavior - a base class for all stylus related editing behaviors
/// </summary>
internal abstract class StylusEditingBehavior : EditingBehavior, IStylusEditing
{
//-------------------------------------------------------------------------------
//
// Constructors
//
//-------------------------------------------------------------------------------
#region Constructors
/// <summary>
/// Constructor
/// </summary>
/// <param name="editingCoordinator"></param>
/// <param name="inkCanvas"></param>
internal StylusEditingBehavior(EditingCoordinator editingCoordinator, InkCanvas inkCanvas)
: base(editingCoordinator, inkCanvas)
{
}
#endregion Constructors
//-------------------------------------------------------------------------------
//
// Internal Methods
//
//-------------------------------------------------------------------------------
#region Internal Methods
/// <summary>
/// An internal method which performs a mode change in mid-stroke.
/// </summary>
/// <param name="mode"></param>
internal void SwitchToMode(InkCanvasEditingMode mode)
{
//
// The dispather frames can be entered. If one calls InkCanvas.Select/Paste from a dispather frame
// during the user editing, this method will be called. But before the method is processed completely,
// the user input could kick in AddStylusPoints. So EditingCoordinator.UserIsEditing flag may be messed up.
// Now we use _disableInput to disable the input during changing the mode in mid-stroke.
_disableInput = true;
try
{
OnSwitchToMode(mode);
}
finally
{
_disableInput = false;
}
}
#endregion Internal Methods
//-------------------------------------------------------------------------------
//
// IStylusEditing Interface
//
//-------------------------------------------------------------------------------
#region IStylusEditing Interface
/// <summary>
/// IStylusEditing.AddStylusPoints
/// </summary>
/// <param name="stylusPoints">stylusPoints</param>
/// <param name="userInitiated">true if the eventArgs source had UserInitiated set to true</param>
void IStylusEditing.AddStylusPoints(StylusPointCollection stylusPoints, bool userInitiated)
{
EditingCoordinator.DebugCheckActiveBehavior(this);
// Don't process if SwitchToMode is called during the mid-stroke.
if ( _disableInput )
{
return;
}
if ( !EditingCoordinator.UserIsEditing )
{
EditingCoordinator.UserIsEditing = true;
StylusInputBegin(stylusPoints, userInitiated);
}
else
{
StylusInputContinue(stylusPoints, userInitiated);
}
}
#endregion IStylusEditing Interface
//-------------------------------------------------------------------------------
//
// Protected Methods
//
//-------------------------------------------------------------------------------
#region Protected Methods
/// <summary>
/// An abstract method which performs a mode change in mid-stroke.
/// </summary>
/// <param name="mode"></param>
protected abstract void OnSwitchToMode(InkCanvasEditingMode mode);
/// <summary>
/// Called when the InkEditingBehavior is activated.
/// </summary>
protected override void OnActivate()
{
}
/// <summary>
/// Called when the InkEditingBehavior is deactivated.
/// </summary>
protected override void OnDeactivate()
{
}
/// <summary>
/// OnCommit
/// </summary>
/// <param name="commit"></param>
protected sealed override void OnCommit(bool commit)
{
// Make sure that user is still editing
if ( EditingCoordinator.UserIsEditing )
{
EditingCoordinator.UserIsEditing = false;
// The follow code raises variety editing events.
// The out-side code could throw exception in the their handlers. We use try/finally block to protect our status.
StylusInputEnd(commit);
}
else
{
// If user isn't editing, we should still call the derive class.
// So the dynamic behavior like LSB can be self deactivated when it has been commited.
OnCommitWithoutStylusInput(commit);
}
}
/// <summary>
/// StylusInputBegin
/// </summary>
/// <param name="stylusPoints">stylusPoints</param>
/// <param name="userInitiated">true if the source eventArgs.UserInitiated flag is true</param>
protected virtual void StylusInputBegin(StylusPointCollection stylusPoints, bool userInitiated)
{
//defer to derived classes
}
/// <summary>
/// StylusInputContinue
/// </summary>
/// <param name="stylusPoints">stylusPoints</param>
/// <param name="userInitiated">true if the source eventArgs.UserInitiated flag is true</param>
protected virtual void StylusInputContinue(StylusPointCollection stylusPoints, bool userInitiated)
{
//defer to derived classes
}
/// <summary>
/// StylusInputEnd
/// </summary>
/// <param name="commit"></param>
protected virtual void StylusInputEnd(bool commit)
{
//defer to derived classes
}
/// <summary>
/// OnCommitWithoutStylusInput
/// </summary>
/// <param name="commit"></param>
protected virtual void OnCommitWithoutStylusInput(bool commit)
{
//defer to derived classes
}
#endregion Protected Methods
//-------------------------------------------------------------------------------
//
// Private Fields
//
//-------------------------------------------------------------------------------
#region Private Fields
private bool _disableInput; // No need for initializing. The default value is false.
#endregion Private Fields
}
}
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