Make FoldingManager independent of TextView.

This allows using a single FoldingManager in multiple TextViews.

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Folding/FoldingElementGenerator.cs

@@ -2,11 +2,11 @@
 // This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
 
 using System;
+using System.Collections.Generic;
 using System.Windows;
 using System.Windows.Input;
 using System.Windows.Media;
 using System.Windows.Media.TextFormatting;
-
 using ICSharpCode.AvalonEdit.Rendering;
 using ICSharpCode.AvalonEdit.Utils;
 
@@ -15,21 +15,57 @@ namespace ICSharpCode.AvalonEdit.Folding
 	/// <summary>
 	/// A <see cref="VisualLineElementGenerator"/> that produces line elements for folded <see cref="FoldingSection"/>s.
 	/// </summary>
-	public class FoldingElementGenerator : VisualLineElementGenerator
+	public sealed class FoldingElementGenerator : VisualLineElementGenerator, ITextViewConnect
 	{
+		readonly List<TextView> textViews = new List<TextView>();
+		FoldingManager foldingManager;
+		
+		#region FoldingManager property / connecting with TextView
 		/// <summary>
 		/// Gets/Sets the folding manager from which the foldings should be shown.
 		/// </summary>
-		public FoldingManager FoldingManager { get; set; }
+		public FoldingManager FoldingManager {
+			get {
+				return foldingManager;
+			}
+			set {
+				if (foldingManager != value) {
+					if (foldingManager != null) {
+						foreach (TextView v in textViews)
+							foldingManager.RemoveFromTextView(v);
+					}
+					foldingManager = value;
+					if (foldingManager != null) {
+						foreach (TextView v in textViews)
+							foldingManager.AddToTextView(v);
+					}
+				}
+			}
+		}
+		
+		void ITextViewConnect.AddToTextView(TextView textView)
+		{
+			textViews.Add(textView);
+			if (foldingManager != null)
+				foldingManager.AddToTextView(textView);
+		}
+		
+		void ITextViewConnect.RemoveFromTextView(TextView textView)
+		{
+			textViews.Remove(textView);
+			if (foldingManager != null)
+				foldingManager.RemoveFromTextView(textView);
+		}
+		#endregion
 		
 		/// <inheritdoc/>
 		public override void StartGeneration(ITextRunConstructionContext context)
 		{
 			base.StartGeneration(context);
-			if (FoldingManager != null) {
+			if (foldingManager != null) {
-				if (context.TextView != FoldingManager.textView)
+				if (!foldingManager.textViews.Contains(context.TextView))
 					throw new ArgumentException("Invalid TextView");
-				if (context.Document != FoldingManager.document)
+				if (context.Document != foldingManager.document)
 					throw new ArgumentException("Invalid document");
 			}
 		}
@@ -37,8 +73,8 @@ namespace ICSharpCode.AvalonEdit.Folding
 		/// <inheritdoc/>
 		public override int GetFirstInterestedOffset(int startOffset)
 		{
-			if (FoldingManager != null)
+			if (foldingManager != null)
-				return FoldingManager.GetNextFoldedFoldingStart(startOffset);
+				return foldingManager.GetNextFoldedFoldingStart(startOffset);
 			else
 				return -1;
 		}
@@ -46,11 +82,11 @@ namespace ICSharpCode.AvalonEdit.Folding
 		/// <inheritdoc/>
 		public override VisualLineElement ConstructElement(int offset)
 		{
-			if (FoldingManager == null)
+			if (foldingManager == null)
 				return null;
 			int foldedUntil = -1;
 			FoldingSection foldingSection = null;
-			foreach (FoldingSection fs in FoldingManager.GetFoldingsAt(offset)) {
+			foreach (FoldingSection fs in foldingManager.GetFoldingsAt(offset)) {
 				if (fs.IsFolded) {
 					if (fs.EndOffset > foldedUntil) {
 						foldedUntil = fs.EndOffset;

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Folding/FoldingManager.cs

@@ -20,27 +20,33 @@ namespace ICSharpCode.AvalonEdit.Folding
 	/// </summary>
 	public class FoldingManager : IWeakEventListener
 	{
-		internal readonly TextView textView;
 		internal readonly TextDocument document;
 		
+		internal readonly List<TextView> textViews = new List<TextView>();
 		readonly TextSegmentCollection<FoldingSection> foldings;
 		
 		#region Constructor
 		/// <summary>
 		/// Creates a new FoldingManager instance.
 		/// </summary>
-		public FoldingManager(TextView textView, TextDocument document)
+		public FoldingManager(TextDocument document)
 		{
-			if (textView == null)
-				throw new ArgumentNullException("textView");
 			if (document == null)
 				throw new ArgumentNullException("document");
-			this.textView = textView;
 			this.document = document;
 			this.foldings = new TextSegmentCollection<FoldingSection>();
 			document.VerifyAccess();
 			TextDocumentWeakEventManager.Changed.AddListener(document, this);
 		}
+		
+		/// <summary>
+		/// Creates a new FoldingManager instance.
+		/// </summary>
+		[Obsolete("Use the (TextDocument) constructor instead.")]
+		public FoldingManager(TextView textView, TextDocument document)
+			: this(document)
+		{
+		}
 		#endregion
 		
 		#region ReceiveWeakEvent
@@ -73,6 +79,57 @@ namespace ICSharpCode.AvalonEdit.Folding
 		}
 		#endregion
 		
+		#region Manage TextViews
+		internal void AddToTextView(TextView textView)
+		{
+			if (textView == null || textViews.Contains(textView))
+				throw new ArgumentException();
+			textViews.Add(textView);
+			foreach (FoldingSection fs in foldings) {
+				if (fs.collapsedSections != null) {
+					Array.Resize(ref fs.collapsedSections, textViews.Count);
+					fs.collapsedSections[fs.collapsedSections.Length - 1] = fs.CollapseSection(textView);
+				}
+			}
+		}
+		
+		internal void RemoveFromTextView(TextView textView)
+		{
+			int pos = textViews.IndexOf(textView);
+			if (pos < 0)
+				throw new ArgumentException();
+			foreach (FoldingSection fs in foldings) {
+				if (fs.collapsedSections != null) {
+					CollapsedLineSection[] c = new CollapsedLineSection[textViews.Count];
+					Array.Copy(fs.collapsedSections, 0, c, 0, pos);
+					Array.Copy(fs.collapsedSections, pos + 1, c, pos, c.Length - pos);
+					fs.collapsedSections = c;
+				}
+			}
+		}
+		
+		internal CollapsedLineSection[] CollapseLines(DocumentLine start, DocumentLine end)
+		{
+			CollapsedLineSection[] c = new CollapsedLineSection[textViews.Count];
+			for (int i = 0; i < c.Length; i++) {
+				c[i] = textViews[i].CollapseLines(start, end);
+			}
+			return c;
+		}
+		
+		internal void Redraw()
+		{
+			foreach (TextView textView in textViews)
+				textView.Redraw();
+		}
+		
+		internal void Redraw(FoldingSection fs)
+		{
+			foreach (TextView textView in textViews)
+				textView.Redraw(fs);
+		}
+		#endregion
+		
 		#region Create / Remove / Clear
 		/// <summary>
 		/// Creates a folding for the specified text section.
@@ -83,7 +140,7 @@ namespace ICSharpCode.AvalonEdit.Folding
 				throw new ArgumentException("startOffset must be less than endOffset");
 			FoldingSection fs = new FoldingSection(this, startOffset, endOffset);
 			foldings.Add(fs);
-			textView.Redraw(fs, DispatcherPriority.Normal);
+			Redraw(fs);
 			return fs;
 		}
 		
@@ -96,7 +153,7 @@ namespace ICSharpCode.AvalonEdit.Folding
 				throw new ArgumentNullException("fs");
 			fs.IsFolded = false;
 			foldings.Remove(fs);
-			textView.Redraw(fs, DispatcherPriority.Normal);
+			Redraw(fs);
 		}
 		
 		/// <summary>
@@ -108,7 +165,7 @@ namespace ICSharpCode.AvalonEdit.Folding
 			foreach (FoldingSection s in foldings)
 				s.IsFolded = false;
 			foldings.Clear();
-			textView.Redraw();
+			Redraw();
 		}
 		#endregion
 		
@@ -264,7 +321,7 @@ namespace ICSharpCode.AvalonEdit.Folding
 			FoldingMargin margin;
 			FoldingElementGenerator generator;
 			
-			public FoldingManagerInstallation(TextArea textArea) : base(textArea.TextView, textArea.Document)
+			public FoldingManagerInstallation(TextArea textArea) : base(textArea.Document)
 			{
 				this.textArea = textArea;
 				margin = new FoldingMargin() { FoldingManager = this };

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Folding/FoldingSection.cs

@@ -13,9 +13,9 @@ namespace ICSharpCode.AvalonEdit.Folding
 	/// </summary>
 	public sealed class FoldingSection : TextSegment
 	{
-		FoldingManager manager;
+		readonly FoldingManager manager;
 		bool isFolded;
-		CollapsedLineSection collapsedSection;
+		internal CollapsedLineSection[] collapsedSections;
 		string title;
 		
 		/// <summary>
@@ -32,18 +32,29 @@ namespace ICSharpCode.AvalonEdit.Folding
 							DocumentLine endLine = manager.document.GetLineByOffset(EndOffset);
 							if (startLine != endLine) {
 								DocumentLine startLinePlusOne = startLine.NextLine;
-								collapsedSection = manager.textView.CollapseLines(startLinePlusOne, endLine);
+								collapsedSections = manager.CollapseLines(startLinePlusOne, endLine);
 							}
 						}
 					} else {
 						RemoveCollapsedLineSection();
 					}
 					if (manager != null)
-						manager.textView.Redraw(this, DispatcherPriority.Normal);
+						manager.Redraw(this);
 				}
 			}
 		}
 		
+		internal CollapsedLineSection CollapseSection(TextView textView)
+		{
+			DocumentLine startLine = manager.document.GetLineByOffset(StartOffset);
+			DocumentLine endLine = manager.document.GetLineByOffset(EndOffset);
+			if (startLine != endLine) {
+				DocumentLine startLinePlusOne = startLine.NextLine;
+				return textView.CollapseLines(startLinePlusOne, endLine);
+			}
+			return null;
+		}
+		
 		/// <summary>
 		/// Gets/Sets the text used to display the collapsed version of the folding section.
 		/// </summary>
@@ -55,7 +66,7 @@ namespace ICSharpCode.AvalonEdit.Folding
 				if (title != value) {
 					title = value;
 					if (this.IsFolded && manager != null)
-						manager.textView.Redraw(this, DispatcherPriority.Normal);
+						manager.Redraw(this);
 				}
 			}
 		}
@@ -74,16 +85,13 @@ namespace ICSharpCode.AvalonEdit.Folding
 		
 		void RemoveCollapsedLineSection()
 		{
-			if (collapsedSection != null) {
+			if (collapsedSections != null) {
-				if (collapsedSection.Start != null)
+				foreach (var collapsedSection in collapsedSections) {
-					collapsedSection.Uncollapse();
+					if (collapsedSection != null && collapsedSection.Start != null)
-				collapsedSection = null;
+						collapsedSection.Uncollapse();
+				}
+				collapsedSections = null;
 			}
 		}
-		
-		internal void Removed()
-		{
-			manager = null;
-		}
 	}
 }

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Rendering/CollapsedLineSection.cs

@@ -30,7 +30,9 @@ namespace ICSharpCode.AvalonEdit.Rendering
 			this.start = start;
 			this.end = end;
 			#if DEBUG
-			this.ID = "#" + (nextId++);
+			unchecked {
+				this.ID = " #" + (nextId++);
+			}
 			#endif
 		}
 		
@@ -110,7 +112,7 @@ namespace ICSharpCode.AvalonEdit.Rendering
 		[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Globalization", "CA1305:SpecifyIFormatProvider", MessageId = "System.Int32.ToString")]
 		public override string ToString()
 		{
-			return "[CollapsedSection " + ID + " Start=" + (start != null ? start.LineNumber.ToString() : "null")
+			return "[CollapsedSection" + ID + " Start=" + (start != null ? start.LineNumber.ToString() : "null")
 				+ " End=" + (end != null ? end.LineNumber.ToString() : "null") + " IsCollapsed=" + isCollapsed + "]";
 		}
 	}

src/Libraries/AvalonEdit/ICSharpCode.AvalonEdit/Rendering/TextView.cs

@@ -406,7 +406,7 @@ namespace ICSharpCode.AvalonEdit.Rendering
 		/// <summary>
 		/// Causes the text editor to regenerate the specified visual line.
 		/// </summary>
-		public void Redraw(VisualLine visualLine, DispatcherPriority redrawPriority)
+		public void Redraw(VisualLine visualLine, DispatcherPriority redrawPriority = DispatcherPriority.Normal)
 		{
 			VerifyAccess();
 			if (allVisualLines.Remove(visualLine)) {
@@ -419,7 +419,7 @@ namespace ICSharpCode.AvalonEdit.Rendering
 		/// <summary>
 		/// Causes the text editor to redraw all lines overlapping with the specified segment.
 		/// </summary>
-		public void Redraw(int offset, int length, DispatcherPriority redrawPriority)
+		public void Redraw(int offset, int length, DispatcherPriority redrawPriority = DispatcherPriority.Normal)
 		{
 			VerifyAccess();
 			bool removedLine = false;
@@ -464,7 +464,7 @@ namespace ICSharpCode.AvalonEdit.Rendering
 		/// Causes the text editor to redraw all lines overlapping with the specified segment.
 		/// Does nothing if segment is null.
 		/// </summary>
-		public void Redraw(ISegment segment, DispatcherPriority redrawPriority)
+		public void Redraw(ISegment segment, DispatcherPriority redrawPriority = DispatcherPriority.Normal)
 		{
 			if (segment != null) {
 				Redraw(segment.Offset, segment.Length, redrawPriority);