private IContextMenuTarget FindRightTarget(TargetList targets, Rectangle currentRect)
{
// We compare from the right edge always
currentRect.X = currentRect.Right;
currentRect.Width = 0;
// Best match found so far
IContextMenuTarget nextTarget = null;
Rectangle nextRect = Rectangle.Empty;
// Search all targets, looking for a better match than the current best
foreach (IContextMenuTarget target in targets)
{
Rectangle targetRect = target.ClientRectangle;
// Only interested in targets that are after the current one
if (targetRect.Left >= currentRect.Right)
{
// It nothing found so far, it automatically becomes the best match
if (nextTarget == null)
{
nextTarget = target;
nextRect = targetRect;
}
else
{
double currentDistance = CenterDistance(currentRect, new Rectangle(nextRect.X, nextRect.Y, 0, nextRect.Height));
double nextDistance = CenterDistance(currentRect, new Rectangle(targetRect.X, targetRect.Y, 0, targetRect.Height));
// If next target is nearer than the current best...
if (nextDistance < currentDistance)
{
//...then it becomes the new best match
nextTarget = target;
nextRect = targetRect;
}
}
}
}
return(nextTarget);
}
private void OnDelayTimerExpire(object sender, EventArgs e)
{
if (_itemDelayTimer != null)
{
_itemDelayTimer.Stop();
// If the target and current sub menu target are the same, then there is nothing
// to do as we would only tell the sub menu to be removed and shown again.
if (_target != _targetSubMenu)
{
// Do we know a target that was instructed to show any sub menu?
if (_targetSubMenu != null)
{
// Inform the same target to remove any showing sub menu
_targetSubMenu.ClearSubMenu();
_targetSubMenu = null;
}
// If we still have a target and it has a sub menu
if (_target is { HasSubMenu : true })
/// <summary>
/// Set the provided target as the current target.
/// </summary>
/// <param name="target">Reference to the new target.</param>
/// <param name="startTimer">Should a timer be started for handling sub menu showing.</param>
public void SetTarget(IContextMenuTarget target, bool startTimer)
{
// Only interested in a change of target
if (_target != target)
{
// Tell current target to reset drawing
if (_target != null)
{
_itemDelayTimer.Stop();
_target.ClearTarget();
_target = null;
}
// Shift the active view to the new target
if (target != null)
{
ActiveView = target.GetActiveView();
}
else
{
ActiveView = null;
}
_target = target;
// Tell new target to draw as highlighted and start delay timer
if (_target != null)
{
_itemDelayTimer.Stop();
if (startTimer)
{
_itemDelayTimer.Start();
}
_target.ShowTarget();
}
}
}
/// <summary>
/// Handle right key being pressed.
/// </summary>
public void KeyRight()
{
TargetList targets = ConstructKeyboardTargets(Root);
// Find the next appropriate target
IContextMenuTarget newTarget = null;
if (_target == null)
{
newTarget = FindTopLeftTarget(targets);
}
else
{
newTarget = FindRightTarget(targets, _target);
}
// If we found a new target, then make it the current target
if ((newTarget != null) && (newTarget != _target))
{
SetTarget(newTarget, false);
}
}
/// <summary>
/// Set the provided target as the current target and it is already showing a sub menu
/// </summary>
public void SetTargetSubMenu(IContextMenuTarget target)
{
// Kill any running timer
if (_itemDelayTimer != null)
{
_itemDelayTimer.Stop();
}
// If the currently showing sub menu is not for the new target
if (_targetSubMenu != target)
{
// Do we know a target that was instructed to show any sub menu?
if (_targetSubMenu != null)
{
// Inform the same target to remove any showing sub menu
_targetSubMenu.ClearSubMenu();
_targetSubMenu = null;
}
// Remember the new sub menu target
_targetSubMenu = target;
}
// Tell current target to reset drawing
if (_target != target)
{
_target.ClearTarget();
_target = null;
}
_target = target;
// Tell new target to draw as highlighted and start delay timer
if (_target != null)
{
_target.ShowTarget();
}
}
/// <summary>
/// Clean up any resources.
/// </summary>
public override void Dispose()
{
if (_itemDelayTimer != null)
{
_itemDelayTimer.Stop();
_itemDelayTimer.Dispose();
_itemDelayTimer = null;
}
if (_targetSubMenu != null)
{
_targetSubMenu.ClearSubMenu();
_targetSubMenu = null;
}
if (_target != null)
{
_target.ClearTarget();
_target = null;
}
base.Dispose();
}