private void UpdateCanExecute()
{
if (IsCommandExecuting)
{
return;
}
IsCommandExecuting = true;
try
{
//use our custom class as the parameter
var parameter = new CommandCanExecuteParameter(null);
CommandUtil.CanExecute(this, parameter);
//we set the current status independent on whether the command can execute
{
if (parameter.CurrentValue is bool)
{
IsChecked = (bool)parameter.CurrentValue;
}
else
{
IsChecked = false;
}
}
}
finally
{
IsCommandExecuting = false;
}
}
protected virtual void UpdateCanExecute()
{
if (IsCommandExecuting)
{
return;
}
ICommand cmd = Command;
if (cmd == null)
{
IsEnabled = true;
}
else
{
try
{
IsCommandExecuting = true;
IsEnabled = CommandUtil.CanExecute(this, CommandParameter);
var ca = new CommandCanExecuteParameter(CommandParameter);
CommandUtil.CanExecute(this, ca);
object value = ca.CurrentValue;
//if (value is RangedValue)
// value = ((RangedValue) value).Value;
object o = FindItemByData(value);
if (o == null && value == null)
{
Text = null;
SelectedItem = null;
}
else if (o != null && !Equals(SelectedItem, o))
{
SelectedItem = o;
}
else if (IsEditable && !IsReadOnly &&
value != null && Text != value.ToString())
{
Text = value.ToString();
}
}
finally { IsCommandExecuting = false; }
}
}