CanStartWork Method (original) (raw)
Summary
Gets a value that indicates whether the mode can start work.
Example
using Leadtools;
using Leadtools.Controls;
using Leadtools.Codecs;
using Leadtools.Drawing;
using Leadtools.ImageProcessing;
using Leadtools.ImageProcessing.Color;
private class TransformInteractiveMode : ImageViewerInteractiveMode
{
public TransformInteractiveMode() :
base()
{
this.AutoItemMode = ImageViewerAutoItemMode.AutoSet;
}
private Keys _scaleKeyModifier = Keys.Control;
public virtual Keys ScaleKeyModifier
{
get { return _scaleKeyModifier; }
set
{
// Supported is none and any modifiers
switch (value)
{
case Keys.None:
case Keys.Alt:
case Keys.Shift:
case Keys.Control:
_scaleKeyModifier = value;
break;
default:
throw new ArgumentException("Invalid value", "ScaleKeyModifier");
}
}
}
private Keys _rotateKeyModifier = Keys.Alt;
public virtual Keys RotateKeyModifier
{
get { return _rotateKeyModifier; }
set
{
// Supported is none and any modifiers
switch (value)
{
case Keys.None:
case Keys.Alt:
case Keys.Shift:
case Keys.Control:
_rotateKeyModifier = value;
break;
default:
throw new ArgumentException("Invalid value", "PageKeyModifier");
}
}
}
public override string Name
{
get { return "Transform"; }
}
public override int Id
{
get { return ImageViewerInteractiveMode.UserModeId + 3; }
}
public override void Start(ImageViewer imageViewer)
{
base.Start(imageViewer);
var service = base.InteractiveService;
// Pan required events
service.DragStarted += new EventHandler<InteractiveDragStartedEventArgs>(service_DragStarted);
service.DragDelta += new EventHandler<InteractiveDragDeltaEventArgs>(service_DragDelta);
service.DragCompleted += new EventHandler<InteractiveDragCompletedEventArgs>(service_DragCompleted);
service.DoubleTap += new EventHandler<InteractiveEventArgs>(service_DoubleTap);
}
public override void Stop(ImageViewer imageViewer)
{
if (IsStarted)
{
var service = base.InteractiveService;
service.DragStarted -= new EventHandler<InteractiveDragStartedEventArgs>(service_DragStarted);
service.DragDelta -= new EventHandler<InteractiveDragDeltaEventArgs>(service_DragDelta);
service.DragCompleted -= new EventHandler<InteractiveDragCompletedEventArgs>(service_DragCompleted);
service.DoubleTap -= new EventHandler<InteractiveEventArgs>(service_DoubleTap);
base.Stop(imageViewer);
}
}
private void service_DragStarted(object sender, InteractiveDragStartedEventArgs e)
{
// Make sure pinch is not working, otherwise, ignore pan
if (!this.CanStartWork(e))
return;
// Make sure we are on an item
if (this.Item == null)
return;
e.IsHandled = true;
this.OnWorkStarted(EventArgs.Empty);
}
private void service_DragDelta(object sender, InteractiveDragDeltaEventArgs e)
{
if (!this.IsWorking)
return;
var item = this.Item;
if (item == null)
return;
// Find out what to do
var dx = e.Change.X;
var dy = e.Change.Y;
if (dx == 0 && dy == 0)
return;
var scaleKeyModifier = this.ScaleKeyModifier;
var rotateKeyModifier = this.RotateKeyModifier;
var scale = (Control.ModifierKeys & scaleKeyModifier) == scaleKeyModifier;
var rotate = (Control.ModifierKeys & rotateKeyModifier) == rotateKeyModifier;
var imageViewer = this.ImageViewer;
if (scale)
{
Scale(imageViewer, item, dy, e.Origin);
}
else if (rotate)
{
Rotate(imageViewer, item, dx, e.Origin);
}
else
{
Translate(imageViewer, item, dx, dy);
}
e.IsHandled = true;
}
private void service_DragCompleted(object sender, InteractiveDragCompletedEventArgs e)
{
if (!this.IsWorking)
return;
e.IsHandled = true;
OnWorkCompleted(EventArgs.Empty);
}
private void service_DoubleTap(object sender, InteractiveEventArgs e)
{
// Make sure we not working already
if (this.IsWorking || !this.CanStartWork(e))
return;
// Make sure we have an item
var item = this.Item;
if (item == null)
return;
e.IsHandled = true;
this.OnWorkStarted(EventArgs.Empty);
Identity(this.ImageViewer, item);
this.OnWorkCompleted(EventArgs.Empty);
}
private void Identity(ImageViewer imageViewer, ImageViewerItem item)
{
item.Transform = LeadMatrix.Identity;
}
private void Scale(ImageViewer imageViewer, ImageViewerItem item, int dy, LeadPoint position)
{
// ...
// set scale code
// ...
}
private void Rotate(ImageViewer imageViewer, ImageViewerItem item, int dx, LeadPoint position)
{
// ...
// set rotate code
// ...
}
private void Translate(ImageViewer imageViewer, ImageViewerItem item, int dx, int dy)
{
// ...
// set translate code
// ...
}
}
public void ImageViewerInteractiveMode_Example()
{
_imageViewer.InteractiveModes.BeginUpdate();
_imageViewer.InteractiveModes.Add(new TransformInteractiveMode { IsEnabled = false });
//...
//...
//...
_imageViewer.InteractiveModes.EndUpdate();
}