public bool ProcessMessage(string message)
{
// Note: Post() to UI thread is expensive, and can saturate the message pump when there's a lot of output,
// making UI non-responsive. So avoid using it unless we need it - and we only need it for FlushOutput,
// and we only need it to handle CR.
if (message.Length > 1 && message[0] == '\r' && message[1] != '\n')
{
_coreShell.MainThread().Post(() => {
// Make sure output buffer is up to date
_interactiveWindow.FlushOutput();
// If message starts with CR we remember current output buffer
// length so we can continue writing lines into the same spot.
// See txtProgressBar in R.
// Store the message and the initial position. All subsequent
// messages that start with CR will be written into the same place.
if (_messagePos != null)
{
ProcessReplacement();
}
// Locate last end of line
var snapshot = _interactiveWindow.OutputBuffer.CurrentSnapshot;
var line = snapshot.GetLineFromPosition(snapshot.Length);
var text = message.Substring(1);
_messagePos = new MessagePos()
{
Text = text,
Position = line.Start,
PlaceholderLength = text.Length + 8 // buffer for, say, '| 100%'
};
// It is important that replacement matches original text length
// since interactive window creates fixed colorized spans for errors
// and replacement of text by a text with a different length
// causes odd changes in color - word may appear partially in
// black and partially in red.
// Replacement placeholder so we can receive 'buffer changed' event
// Placeholder is whitespace that is as long as original message plus
// few more space to account for example, for 0% - 100% when CR is used
// to display ASCII progress.
var placeholder = new string(' ', _messagePos.PlaceholderLength);
_interactiveWindow.Write(placeholder);
_interactiveWindow.FlushOutput(); // Must flush so we do get 'buffer changed' immediately.
});
return(true);
}
return(false);
}
internal void WriteFrameworkElement(System.Windows.UIElement control, System.Windows.Size desiredSize)
{
if (_window == null)
{
return;
}
_window.Write("");
_window.FlushOutput();
var caretPos = _window.TextView.Caret.Position.BufferPosition;
var manager = InlineReplAdornmentProvider.GetManager(_window.TextView);
manager.AddAdornment(new ZoomableInlineAdornment(control, _window.TextView, desiredSize), caretPos);
}
private void FlushOutput(IInteractiveWindow window)
{
// Give interactive window writer time to process message queue
UIThreadHelper.Instance.DoEvents(400);
window.FlushOutput();
}
