|
// 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.
//
// Description:
// Ink Collection Behavior
//
// Authors: alexz/samgeo/bkrantz
//
using System.Windows;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Controls;
using System.Windows.Ink;
namespace MS.Internal.Ink
{
/// <summary>
/// InkCollectionBehavior
/// </summary>
internal sealed class InkCollectionBehavior : StylusEditingBehavior
{
//-------------------------------------------------------------------------------
//
// Constructors
//
//-------------------------------------------------------------------------------
#region Constructors
internal InkCollectionBehavior(EditingCoordinator editingCoordinator, InkCanvas inkCanvas)
: base(editingCoordinator, inkCanvas)
{
_stylusPoints = null;
_userInitiated = false;
}
#endregion Constructors
/// <summary>
/// A method which flags InkCollectionBehavior when it needs to reset the dynamic renderer.
/// Called By:
/// EditingCoordinator.OnInkCanvasDeviceDown
/// </summary>
internal void ResetDynamicRenderer()
{
_resetDynamicRenderer = true;
}
//-------------------------------------------------------------------------------
//
// Protected Methods
//
//-------------------------------------------------------------------------------
#region Protected Methods
/// <summary>
/// Overrides SwitchToMode
/// As the following expected results
/// 1. From Ink To InkAndGesture
/// Packets between StylusDown and StylusUp are sent to the gesture reco. On StylusUp gesture event fires. If it’s not a gesture, StrokeCollected event fires.
/// 2. From Ink To GestureOnly
/// Packets between StylusDown and StylusUp are send to the gesture reco. On StylusUp gesture event fires. Stroke gets removed on StylusUp even if it’s not a gesture.
/// 3. From Ink To EraseByPoint
/// Stroke is discarded. PointErasing is performed after changing the mode.
/// 4. From Ink To EraseByStroke
/// Stroke is discarded. StrokeErasing is performed after changing the mode.
/// 5. From Ink To Select
/// Stroke is discarded. Lasso is drawn for all packets between StylusDown and StylusUp. Strokes/elements within the lasso will be selected.
/// 6. From Ink To None
/// Stroke is discarded.
/// 7. From InkAndGesture To Ink
/// Stroke is collected for all packets between StylusDown and StylusUp. Gesture event does not fire.
/// 8. From InkAndGesture To GestureOnly
/// Packets between StylusDown and StylusUp are sent to the gesture reco. Stroke gets removed on StylusUp even if it’s not a gesture.
/// 9. From InkAndGesture To EraseByPoint
/// Stroke is discarded. PointErasing is performed after changing the mode, gesture event does not fire.
/// 10. From InkAndGesture To EraseByStroke
/// Stroke is discarded. StrokeErasing is performed after changing the mode, gesture event does not fire.
/// 11. From InkAndGesture To Select
/// Lasso is drawn for all packets between StylusDown and StylusUp. Strokes/elements within the lasso will be selected.
/// 12. From InkAndGesture To None
/// Stroke is discarded, no gesture is recognized.
/// 13. From GestureOnly To InkAndGesture
/// Packets between StylusDown and StylusUp are sent to the gesture reco. On StylusUp gesture event fires. If it’s not a gesture, StrokeCollected event fires.
/// 14. From GestureOnly To Ink
/// Stroke is collected. Gesture event does not fire.
/// 15. From GestureOnly To EraseByPoint
/// Stroke is discarded PointErasing is performed after changing the mode, gesture event does not fire
/// 16. From GestureOnly To EraseByStroke
/// Stroke is discarded. StrokeErasing is performed after changing the mode, gesture event does not fire.
/// 17. From GestureOnly To Select
/// Lasso is drawn for all packets between StylusDown and StylusUp. Strokes/elements within the lasso will be selected.
/// 18. From GestureOnly To None
/// Stroke is discarded. Gesture event does not fire.
/// </summary>
/// <param name="mode"></param>
protected override void OnSwitchToMode(InkCanvasEditingMode mode)
{
Debug.Assert(EditingCoordinator.IsInMidStroke, "SwitchToMode should only be called in a mid-stroke");
switch ( mode )
{
case InkCanvasEditingMode.Ink:
case InkCanvasEditingMode.InkAndGesture:
case InkCanvasEditingMode.GestureOnly:
{
// We are under one of those Ink modes now. Nothing to change here except raising the mode change event.
InkCanvas.RaiseActiveEditingModeChanged(new RoutedEventArgs(InkCanvas.ActiveEditingModeChangedEvent, InkCanvas));
break;
}
case InkCanvasEditingMode.EraseByPoint:
case InkCanvasEditingMode.EraseByStroke:
{
// Discard the collected ink.
Commit(false);
// Change the Erase mode
EditingCoordinator.ChangeStylusEditingMode(this, mode);
break;
}
case InkCanvasEditingMode.Select:
{
// Make a copy of the current cached points.
StylusPointCollection cachedPoints = _stylusPoints != null ?
_stylusPoints.Clone() : null;
// Discard the collected ink.
Commit(false);
// Change the Select mode
IStylusEditing newBehavior = EditingCoordinator.ChangeStylusEditingMode(this, mode);
if ( cachedPoints != null
// NOTICE-2006/04/27-WAYNEZEN,
// EditingCoordinator.ChangeStylusEditingMode raises external event.
// The user code could take any arbitrary action for instance calling InkCanvas.ReleaseMouseCapture()
// So there is no guarantee that we could receive the newBehavior.
&& newBehavior != null)
{
// Now add the previous points to the lasso behavior
// The SelectionBehavior doesn't check userInitiated, pass false
// even if our _userInitiated flag is true
newBehavior.AddStylusPoints(cachedPoints, false/*userInitiated*/);
}
break;
}
case InkCanvasEditingMode.None:
{
// Discard the collected ink.
Commit(false);
// Change to the None mode
EditingCoordinator.ChangeStylusEditingMode(this, mode);
break;
}
default:
Debug.Assert(false, "Unknown InkCanvasEditingMode!");
break;
}
}
/// <summary>
/// OnActivate
/// </summary>
protected override void OnActivate()
{
base.OnActivate();
// Enable RealTimeInking.
if (InkCanvas.InternalDynamicRenderer != null)
{
InkCanvas.InternalDynamicRenderer.Enabled = true;
InkCanvas.UpdateDynamicRenderer(); // Kick DynamicRenderer to be hooked up to renderer.
}
//if we're activated in PreviewStylusDown or in mid-stroke, the DynamicRenderer will miss the down
//and will not ink. If that is the case, flag InkCollectionBehavior to reset RTI.
_resetDynamicRenderer = EditingCoordinator.StylusOrMouseIsDown;
}
/// <summary>
/// OnDeactivate
/// </summary>
protected override void OnDeactivate()
{
base.OnDeactivate();
// Disable RealTimeInking.
if (InkCanvas.InternalDynamicRenderer != null)
{
InkCanvas.InternalDynamicRenderer.Enabled = false;
InkCanvas.UpdateDynamicRenderer(); // Kick DynamicRenderer to be removed from renderer.
}
}
/// <summary>
/// Get Pen Cursor
/// </summary>
/// <returns></returns>
protected override Cursor GetCurrentCursor()
{
if ( EditingCoordinator.UserIsEditing == true )
{
return Cursors.None;
}
else
{
return PenCursor;
}
}
/// <summary>
/// StylusInputBegin
/// </summary>
/// <param name="stylusPoints">stylusPoints</param>
/// <param name="userInitiated">true if the source eventArgs.UserInitiated flag was set to true</param>
protected override void StylusInputBegin(StylusPointCollection stylusPoints, bool userInitiated)
{
_userInitiated = false;
//we only initialize to true if the first stylusPoints were user initiated
if (userInitiated)
{
_userInitiated = true;
}
_stylusPoints = new StylusPointCollection(stylusPoints.Description, 100);
_stylusPoints.Add(stylusPoints);
_strokeDrawingAttributes = this.InkCanvas.DefaultDrawingAttributes.Clone();
// Reset the dynamic renderer if it's been flagged.
if ( _resetDynamicRenderer )
{
InputDevice inputDevice = EditingCoordinator.GetInputDeviceForReset();
if ( InkCanvas.InternalDynamicRenderer != null && inputDevice != null )
{
StylusDevice stylusDevice = inputDevice as StylusDevice;
// If the input device is MouseDevice, null will be passed in Reset Method.
InkCanvas.InternalDynamicRenderer.Reset(stylusDevice, stylusPoints);
}
_resetDynamicRenderer = false;
}
// Call InvalidateBehaviorCursor at the end of the routine. The method will cause an external event fired.
// So it should be invoked after we set up our states.
EditingCoordinator.InvalidateBehaviorCursor(this);
}
/// <summary>
/// StylusInputContinue
/// </summary>
/// <param name="stylusPoints">stylusPoints</param>
/// <param name="userInitiated">true if the source eventArgs.UserInitiated flag was set to true</param>
protected override void StylusInputContinue(StylusPointCollection stylusPoints, bool userInitiated)
{
//we never set _userInitated to true after it is initialized, only to false
if (!userInitiated)
{
_userInitiated = false;
}
_stylusPoints.Add(stylusPoints);
}
/// <summary>
/// StylusInputEnd
/// </summary>
/// <param name="commit">commit</param>
protected override void StylusInputEnd(bool commit)
{
// The follow code raises Gesture and/or StrokeCollected event
// The out-side code could throw exception in the their handlers. We use try/finally block to protect our status.
try
{
if ( commit )
{
//
// It's possible that the input may end up without any StylusPoint being collected since the behavior can be deactivated by
// the user code in the any event handler.
if ( _stylusPoints != null )
{
Debug.Assert(_strokeDrawingAttributes != null, "_strokeDrawingAttributes can not be null, did we not see a down?");
Stroke stroke =
new Stroke(_stylusPoints, _strokeDrawingAttributes);
//we don't add the stroke to the InkCanvas stroke collection until RaiseStrokeCollected
//since this might be a gesture and in some modes, gestures don't get added
InkCanvasStrokeCollectedEventArgs argsStroke = new InkCanvasStrokeCollectedEventArgs(stroke);
InkCanvas.RaiseGestureOrStrokeCollected(argsStroke, _userInitiated);
}
}
}
finally
{
_stylusPoints = null;
_strokeDrawingAttributes = null;
_userInitiated = false;
EditingCoordinator.InvalidateBehaviorCursor(this);
}
}
/// <summary>
/// ApplyTransformToCursor
/// </summary>
protected override void OnTransformChanged()
{
// Drop the cached pen cursor.
_cachedPenCursor = null;
}
#endregion Protected Methods
//-------------------------------------------------------------------------------
//
// Private Methods
//
//-------------------------------------------------------------------------------
#region Private Methods
private Cursor PenCursor
{
get
{
// We only update our cache cursor when DefaultDrawingAttributes has changed or
// there are animated transforms being applied to InkCanvas.
if ( _cachedPenCursor == null || _cursorDrawingAttributes != InkCanvas.DefaultDrawingAttributes )
{
//adjust the DA for any Layout/Render transforms.
Matrix xf = GetElementTransformMatrix();
DrawingAttributes da = this.InkCanvas.DefaultDrawingAttributes;
if ( !xf.IsIdentity )
{
//scale the DA, zero the offsets.
xf *= da.StylusTipTransform;
xf.OffsetX = 0;
xf.OffsetY = 0;
if ( xf.HasInverse )
{
da = da.Clone();
da.StylusTipTransform = xf;
}
}
_cursorDrawingAttributes = InkCanvas.DefaultDrawingAttributes.Clone();
DpiScale dpi = this.InkCanvas.GetDpi();
_cachedPenCursor = PenCursorManager.GetPenCursor(da, false, (this.InkCanvas.FlowDirection == FlowDirection.RightToLeft), dpi.DpiScaleX, dpi.DpiScaleY);
}
return _cachedPenCursor;
}
}
#endregion Private Methods
//-------------------------------------------------------------------------------
//
// Private Fields
//
//-------------------------------------------------------------------------------
#region Private Fields
// A flag indicates that the dynamic renderer needs to be reset when StylusInputs begins.
private bool _resetDynamicRenderer;
private StylusPointCollection _stylusPoints;
private bool _userInitiated;
/// <summary>
/// We clone the InkCanvas.DefaultDrawingAttributes on down, in case they are
/// changed mid-stroke
/// </summary>
private DrawingAttributes _strokeDrawingAttributes;
/// <summary>
/// The cached DrawingAttributes and Cursor instances for rendering the pen cursor.
/// </summary>
private DrawingAttributes _cursorDrawingAttributes;
private Cursor _cachedPenCursor;
#endregion Private Fields
}
}
|