bluflame/intromat/Intromat/Controls/SourceEditor.cs

using System;
using System.ComponentModel;
using System.Windows;
using ICSharpCode.AvalonEdit;

namespace Intromat.Controls
{
    public class SourceEditor : TextEditor, INotifyPropertyChanged
    {
        /// <summary>
        ///     The bindable text property dependency property
        /// </summary>
        public static readonly DependencyProperty TextProperty = DependencyProperty.Register("Text", typeof(string), typeof(SourceEditor), new FrameworkPropertyMetadata
        {
            DefaultValue = default(string),
            BindsTwoWayByDefault = true,
            PropertyChangedCallback = OnDependencyPropertyChanged
        });

        /// <summary>
        ///     A bindable Text property
        /// </summary>
        public new string Text
        {
            get => (string)GetValue(TextProperty);
            set
            {
                SetValue(TextProperty, value);
                RaisePropertyChanged("Text");
            }
        }

        public event PropertyChangedEventHandler? PropertyChanged;

        protected static void OnDependencyPropertyChanged(DependencyObject obj, DependencyPropertyChangedEventArgs args)
        {
            var target = (SourceEditor)obj;
            if (target.Document == null)
                return;

            var caretOffset = target.CaretOffset;
            var newValue = args.NewValue ?? "";

            target.Document.Text = (string)newValue;
            target.CaretOffset = Math.Min(caretOffset, target.Document.Text.Length);
        }

        protected override void OnTextChanged(EventArgs e)
        {
            if (Document != null)
                Text = Document.Text;

            base.OnTextChanged(e);
        }

        /// <summary>
        ///     Raises a property changed event
        /// </summary>
        /// <param name="property">The name of the property that updates</param>
        public void RaisePropertyChanged(string property)
        {
            if (PropertyChanged != null)
                PropertyChanged(this, new PropertyChangedEventArgs(property));
        }
    }
}