/// <summary>
/// Redraws element when it necessary.
/// </summary>
/// <param name="sender">Element to redraw.</param>
/// <param name="e">Event args.</param>
private void _ElementRedrawRequired(object sender, EventArgs e)
{
IGanttItemElement element = sender as IGanttItemElement;
Debug.Assert(element != null);
GanttItemElementDrawingVisual visual = null;
if (_mapElementToVisual.TryGetValue(element, out visual))
{
visual.RedrawRequired = true;
}
InvalidateVisual();
}
/// <summary>
/// Creates collection of visual from colection of gantt items.
/// </summary>
/// <param name="ganttItems">Gantt items collection.</param>
private void _CreateVisuals(ICollection <IGanttItem> ganttItems)
{
Debug.Assert(ganttItems != null);
foreach (IGanttItem ganttItem in ganttItems)
{
foreach (IGanttItemElement element in ganttItem.GanttItemElements)
{
GanttItemElementDrawingVisual visual = new GanttItemElementDrawingVisual(element);
// Add visual to children collection.
_children.Add(visual);
// Add key-value pair to dictionary.
_mapElementToVisual.Add(element, visual);
element.RedrawRequired += new EventHandler(_ElementRedrawRequired);
}
}
}
/// <summary>
/// Method determines what object is located under point.
/// </summary>
/// <param name="pt">Input point for test.</param>
/// <returns>Returns IGanttItemElement instance if gantt item element presentation is under point.
/// Returns null if nor gantt item nor gantt item element is found under point.</returns>
public object HitTest(Point pt)
{
// Find object under necessary point using Visual tree helper.
HitTestResult foundObject = VisualTreeHelper.HitTest(this, pt);
if (foundObject == null)
{
return(null);
}
GanttItemElementDrawingVisual foundVisual = foundObject.VisualHit as GanttItemElementDrawingVisual;
// If found object is not GanttItemElementDrawingVisual - return null.
if (foundVisual == null)
{
return(null);
}
// If IGanttItemElement was found - return it.
return(foundVisual.GanttItemElement);
}
/// <summary>
/// Adds one "row" of visual elements to necessary gantt item.
/// </summary>
/// <param name="ganttItem">Gantt item.</param>
private void _AddVisualsForGanttItem(IGanttItem ganttItem)
{
// Define next Gantt item in collection to insert new visuals before it's visuals.
int indexOfNextGanttItem = _ganttItems.IndexOf(ganttItem) + 1;
if (indexOfNextGanttItem == _ganttItems.Count) // If new item was added to the end of collection.
{
// Add new visuals to the end of collection.
foreach (IGanttItemElement element in ganttItem.GanttItemElements)
{
GanttItemElementDrawingVisual newVisual = new GanttItemElementDrawingVisual(element);
newVisual.RedrawRequired = true;
_mapElementToVisual.Add(element, newVisual); // Add pair to dictionary.
_children.Add(newVisual);
element.RedrawRequired += new EventHandler(_ElementRedrawRequired);
}
}
else
{
Debug.Assert(false);
// TODO : Add code to insert visual to necessary position later if necessary
}
}
/// <summary>
/// Handler of DragOver event: defines element under drag cursor and initiates Update Layout to highlight it.
/// </summary>
/// <param name="sender">Container.</param>
/// <param name="e">Drag event args.</param>
private void _DragOver(object sender, DragEventArgs e)
{
// Mark previous dragged over element as needed to be redrawn.
if (_draggedOverVisual != null)
_draggedOverVisual.RedrawRequired = true;
// Find object under necessary point using Visual tree helper.
HitTestResult foundObject = VisualTreeHelper.HitTest(this, e.GetPosition(this));
// If there is an element under drag cursor.
if (foundObject != null)
{
// Set element under drag cursor.
_draggedOverVisual = foundObject.VisualHit as GanttItemElementDrawingVisual;
if (_draggedOverVisual != null)
{
// Mark dragged over element as needed to be redrawn.
_draggedOverVisual.RedrawRequired = true;
// Store dragged data.
_draggedData = e.Data;
}
}
// No elements under drug cursor found.
else
{
_draggedOverVisual = null;
}
// Update layout.
InvalidateVisual();
}
/// <summary>
/// Creates collection of visual from colection of gantt items.
/// </summary>
/// <param name="ganttItems">Gantt items collection.</param>
private void _CreateVisuals(ICollection<IGanttItem> ganttItems)
{
Debug.Assert(ganttItems != null);
foreach (IGanttItem ganttItem in ganttItems)
{
foreach (IGanttItemElement element in ganttItem.GanttItemElements)
{
GanttItemElementDrawingVisual visual = new GanttItemElementDrawingVisual(element);
// Add visual to children collection.
_children.Add(visual);
// Add key-value pair to dictionary.
_mapElementToVisual.Add(element, visual);
element.RedrawRequired += new EventHandler(_ElementRedrawRequired);
}
}
}
/// <summary>
/// Adds one "row" of visual elements to necessary gantt item.
/// </summary>
/// <param name="ganttItem">Gantt item.</param>
private void _AddVisualsForGanttItem(IGanttItem ganttItem)
{
// Define next Gantt item in collection to insert new visuals before it's visuals.
int indexOfNextGanttItem = _ganttItems.IndexOf(ganttItem) + 1;
if (indexOfNextGanttItem == _ganttItems.Count) // If new item was added to the end of collection.
{
// Add new visuals to the end of collection.
foreach (IGanttItemElement element in ganttItem.GanttItemElements)
{
GanttItemElementDrawingVisual newVisual = new GanttItemElementDrawingVisual(element);
newVisual.RedrawRequired = true;
_mapElementToVisual.Add(element, newVisual); // Add pair to dictionary.
_children.Add(newVisual);
element.RedrawRequired += new EventHandler(_ElementRedrawRequired);
}
}
else
{
Debug.Assert(false);
// TODO : Add code to insert visual to necessary position later if necessary
}
}
/// <summary>
/// Updates layout after Drag'n'drop finished.
/// </summary>
public void DropGanttItemElements()
{
// If there is an element under drag cursor.
if (_draggedOverVisual != null)
{
// Mark dragged over element as needed to be redrawn.
_draggedOverVisual.RedrawRequired = true;
// Clear dragged over element.
_draggedOverVisual = null;
// Update layout.
InvalidateVisual();
}
}