/// <summary>
/// Raises the <see cref="Selecting" /> event.
/// </summary>
/// <param name="e">The <see cref="TabListCancelEventArgs" /> instance containing the event data.</param>
protected virtual void OnSelecting(TabListCancelEventArgs e)
{
EventHandler <TabListCancelEventArgs> handler;
handler = (EventHandler <TabListCancelEventArgs>) this.Events[_eventSelecting];
handler?.Invoke(this, e);
}
private void ProcessTabChange(int index)
{
if (index != _selectedIndex)
{
TabListCancelEventArgs cancelEventArgs;
TabListPage newPage;
newPage = _pages[index];
// first raise the Selecting event to allow the UI choice to be cancelled
cancelEventArgs = new TabListCancelEventArgs(newPage, index, TabListAction.Selecting);
this.OnSelecting(cancelEventArgs);
if (!cancelEventArgs.Cancel)
{
TabListPage currentPage;
currentPage = this.SelectedPage;
// next, raise the Deselect event (if appropriate), and again check for cancellation
if (currentPage != null)
{
cancelEventArgs = new TabListCancelEventArgs(currentPage, _selectedIndex, TabListAction.Deselecting);
this.OnDeselecting(cancelEventArgs);
}
if (!cancelEventArgs.Cancel)
{
this.SelectedIndex = index;
this.OnSelected(new TabListEventArgs(newPage, index, TabListAction.Selected));
if (currentPage != null)
{
this.OnDeselected(new TabListEventArgs(currentPage, _selectedIndex, TabListAction.Deselected));
}
}
}
}
}
