Auto Height

Or perhaps you might be willing to post a code sample of how you would add this logic?

Hi Nick,

I'll log your request with the related TODO item.  You'd probably need to use something like a FormattedText object with the font that you are using in SyntaxEditor.  In a SyntaxEditor.MeasureOverride override, measure the document text with that and append it onto the size the SyntaxEditor currently measures at (via the base method).

Sounds reasonable. I'll give that a whirl. Thx.

Any pointers on how to measure the line height (to match the LineHeight parameter of the FormattedText type)?

Hi Nick,

I don't think FormattedTextTakes a line height parameter.  Just use whatever font family and size you use on SyntaxEditor.  Then we may also add a pixel or two of padding on each line.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using ActiproSoftware.Windows.Controls.SyntaxEditor;
using System.Windows.Media;
using System.Globalization;
using System.Windows.Controls.Primitives;
using System.Windows;
using System.Windows.Input;
using System.Windows.Controls;
using Connexion.Core;
using ActiproSoftware.Text;

namespace Connexion.Device
{
  public class AutoHeightSyntaxEditor : SyntaxEditor
  {
    public AutoHeightSyntaxEditor()
    {
      VerticalScrollBarVisibility = System.Windows.Controls.ScrollBarVisibility.Disabled;
      HorizontalScrollBarVisibility = System.Windows.Controls.ScrollBarVisibility.Disabled;

      DocumentTextChanged += (o, e) => PerformAutoSizeHeight();
      LayoutUpdated += (o, e) => PerformAutoSizeHeight();
      
      PreviewMouseWheel += (o, e) =>
        {
          e.Handled = true;

          var e2 = new MouseWheelEventArgs(e.MouseDevice, e.Timestamp, e.Delta);
          e2.RoutedEvent = UIElement.MouseWheelEvent;
          e2.Source = o;

          var parent = WPFHelpers.GetParentOfType(this, typeof(ScrollViewer)) as ScrollViewer;
          if (parent != null)
            parent.RaiseEvent(e2);
        };
    }

    public void PerformAutoSizeHeight()
    {
      if (!string.IsNullOrEmpty(Text))
      {
        ActiveView.Scroller.ScrollToDocumentStart();

        // calc margin widths
        double marginWidth = 0;
        foreach (var margin in ActiveView.Margins)
        {
          marginWidth += margin.VisualElement.ActualWidth;
        }

        var collapsedRegions = ActiveView.CollapsedRegionManager.GetCollapsedRanges(new TextSnapshotRange(ActiveView.CurrentSnapshot, 0, ActiveView.CurrentSnapshot.Length));
        StringBuilder text = null;
        bool endsInNewLine = false;

        if (collapsedRegions != null && collapsedRegions.Count > 0)
        {
          text = new StringBuilder(ActiveView.CurrentSnapshot.GetText(LineTerminator.CarriageReturn));
          foreach (var collapsedRgn in collapsedRegions.OrderByDescending(c => c.StartOffset))
          {
            text.Remove(collapsedRgn.StartOffset, collapsedRgn.Length);
          }

          endsInNewLine = text[text.Length - 1] == '\r';
        }
        else
        {
          endsInNewLine = Text.EndsWith("\r") || Text.EndsWith("\n");
        }

        Typeface typeface = new Typeface(FontFamily, FontStyle, FontWeight, FontStretch);
        FormattedText formattedText = new FormattedText(text == null ? Text : text.ToString(), CultureInfo.CurrentCulture, System.Windows.FlowDirection.LeftToRight, typeface, FontSize, Brushes.Black)
        {
          MaxTextWidth = Math.Max(0, ActualWidth - (Margin.Left + Margin.Right + Padding.Left + Padding.Right + marginWidth)),
          LineHeight = 16, // <-- This should be based off the current font + some padding value. Actipro property?
          Trimming = TextTrimming.None,
        };

        Height = formattedText.Height + (endsInNewLine ? formattedText.LineHeight : 0) + (Padding.Top + Padding.Bottom);
      }
    }

  }
}

Hi Nick,

We have been working on this a bit as a possible feature addition for the upcoming 2014.1 version. If you would like to help test this with us, please write our support address and reference this thread. Thanks!

We've announced this feature on our blog as being included for the 2014.1 version:

http://blog.actiprosoftware.com/post/2014/02/26/SyntaxEditor-Auto-Sizing