protected override void OnCropAdjustment(CroppingHandle handle, float distX, float distY)
{
if (photoView.IsCropAllowed(handle, distX, distY))
{
var oldCR = photoView.CroppingRectangle;
var distanceX = distX / photoView.Scale;
var distanceY = distY / photoView.Scale;
switch (handle)
{
case CroppingHandle.Left:
photoView.CroppingRectangle = new Rect((int)(oldCR.Left + distanceX), oldCR.Top, oldCR.Right, oldCR.Bottom);
break;
case CroppingHandle.Right:
photoView.CroppingRectangle = new Rect(oldCR.Left, oldCR.Top, (int)(oldCR.Right + distanceX), oldCR.Bottom);
break;
case CroppingHandle.Top:
photoView.CroppingRectangle = new Rect(oldCR.Left, (int)(oldCR.Top + distanceY), oldCR.Right, oldCR.Bottom);
break;
case CroppingHandle.Bottom:
photoView.CroppingRectangle = new Rect(oldCR.Left, oldCR.Top, oldCR.Right, (int)(oldCR.Bottom + distanceY));
break;
}
}
}
public bool IsCropAllowed(CroppingHandle handle, float distX, float distY)
{
var oldCRDisp = CroppingRectangleOnDisplay;
//Check if it is possible?
switch (handle)
{
case CroppingHandle.Left:
return(oldCRDisp.Right - (oldCRDisp.Left + distX) > MIN_CROP_DISTANCE);
case CroppingHandle.Right:
return((oldCRDisp.Right + distX) - oldCRDisp.Left > MIN_CROP_DISTANCE);
case CroppingHandle.Top:
return(oldCRDisp.Bottom - (oldCRDisp.Top + distY) > MIN_CROP_DISTANCE);
case CroppingHandle.Bottom:
return((oldCRDisp.Bottom + distY) - oldCRDisp.Top > MIN_CROP_DISTANCE);
}
return(false);
}
private (float x, float y) GetCroppingHandle(CroppingHandle handle)
{
var cr = CroppingRectangleOnDisplay;
switch (handle)
{
case CroppingHandle.Left:
return(cr.Left, (cr.Top + cr.Bottom) / 2);
case CroppingHandle.Right:
return(cr.Right, (cr.Top + cr.Bottom) / 2);
case CroppingHandle.Top:
return((cr.Right + cr.Left) / 2, cr.Top);
case CroppingHandle.Bottom:
return((cr.Right + cr.Left) / 2, cr.Bottom);
default:
throw new SystemException("Unsupported handle type");
}
}
protected abstract void OnCropAdjustment(CroppingHandle handle, float distanceX, float distanceY);
protected override void OnCropAdjustment(CroppingHandle handle, float distanceX, float distanceY)
{
//cropping functionality which is not supported here
}