/// <summary>
/// Determines whether the <see cref="ScrollBar.ScrollHereCommand"/> command can execute.
/// </summary>
private static void CanExecuteScrollHereCommand(DependencyObject element, ICommand command, Object parameter, CanExecuteRoutedEventData data)
{
data.CanExecute = true;
}
/// <summary>
/// Determines whether the <see cref="ApplicationCommands.Paste"/> command can execute.
/// </summary>
private static void CanExecutePaste(DependencyObject element, ICommand command, Object parameter, CanExecuteRoutedEventData data)
{
var textEditor = ((TextEditingControl)element).TextEditor;
if (textEditor == null)
{
return;
}
data.CanExecute = textEditor.IsEnabled && !textEditor.IsReadOnly;
data.Handled = true;
}
/// <summary>
/// Determines whether a scroll command can execute.
/// </summary>
private static void CanExecuteScrollCommand(DependencyObject element, ICommand command, Object parameter, CanExecuteRoutedEventData data)
{
data.CanExecute = !((HScrollBar)element).IsPartOfScrollViewer;
}
/// <summary>
/// Determines whether the <see cref="ApplicationCommands.Cut"/> command can execute.
/// </summary>
private static void CanExecuteCut(DependencyObject element, ICommand command, Object parameter, CanExecuteRoutedEventData data)
{
var textEditor = ((TextEditingControl)element).TextEditor;
if (textEditor == null)
{
return;
}
if (textEditor.IsMasked)
{
data.CanExecute = false;
data.Handled = true;
return;
}
data.CanExecute = textEditor.IsEnabled && !textEditor.IsReadOnly && textEditor.SelectionLength > 0;
data.Handled = true;
}
/// <summary>
/// Determines whether the <see cref="EditingCommands.TabBackward"/> command can execute.
/// </summary>
private static void CanExecuteTabBackward(DependencyObject element, ICommand command, Object parameter, CanExecuteRoutedEventData data)
{
var textEditor = ((TextEditingControl)element).TextEditor;
if (textEditor != null && textEditor.AcceptsTab && textEditor.IsEnabled)
{
data.CanExecute = true;
}
else
{
data.ContinueRouting = true;
}
}
/// <summary>
/// Determines whether the <see cref="EditingCommands.EnterParagraphBreak"/> command can execute.
/// </summary>
private static void CanExecuteEnterParagraphBreak(DependencyObject element, ICommand command, Object parameter, CanExecuteRoutedEventData data)
{
var textEditor = ((TextEditingControl)element).TextEditor;
if (textEditor != null && textEditor.AcceptsReturn && textEditor.IsEnabled && !textEditor.IsReadOnly)
{
data.CanExecute = true;
}
else
{
data.ContinueRouting = true;
}
}
/// <summary>
/// Specifies that a command can execute if the text box is enabled and the caret is visible.
/// </summary>
private static void CanExecuteIsCaretVisible(DependencyObject element, ICommand command, Object parameter, CanExecuteRoutedEventData data)
{
var textEditor = ((TextEditingControl)element).TextEditor;
if (textEditor == null || !textEditor.IsEnabled)
{
return;
}
if (textEditor.IsReadOnly && !textEditor.IsReadOnlyCaretVisible)
{
return;
}
data.CanExecute = true;
}
/// <summary>
/// Determines whether a scroll command can execute.
/// </summary>
private static void CanExecuteScrollCommand(DependencyObject element, ICommand command, Object parameter, CanExecuteRoutedEventData data)
{
var scrollBar = element as ScrollBar;
if (scrollBar == null || data.OriginalSource != scrollBar)
{
return;
}
var @continue = data.ContinueRouting;
var orientedScrollBar = (scrollBar.Orientation == Orientation.Horizontal) ? scrollBar.PART_HScrollBar : scrollBar.PART_VScrollBar;
if (orientedScrollBar != null)
{
data.CanExecute = ((RoutedCommand)command).CanExecute(scrollBar.View, parameter, orientedScrollBar, out @continue);
data.Handled = true;
}
data.ContinueRouting = @continue;
}
