Simplified more delegate invocations

Pinta.Core/Actions/AppActions.cs

@@ -59,8 +59,7 @@ public void RegisterHandlers ()
 	#region Event Invokers
 	public void RaiseBeforeQuit ()
 	{
-		if (BeforeQuit != null)
-			BeforeQuit (this, EventArgs.Empty);
+		BeforeQuit?.Invoke (this, EventArgs.Empty);
 	}
 	#endregion
 }

Pinta.Core/Actions/FileActions.cs

@@ -121,8 +121,7 @@ internal int RaiseModifyCompression (int defaultCompression, Gtk.Window parent)
 	{
 		ModifyCompressionEventArgs e = new ModifyCompressionEventArgs (defaultCompression, parent);
 
-		if (ModifyCompression != null)
-			ModifyCompression (this, e);
+		ModifyCompression?.Invoke (this, e);
 
 		return e.Cancel ? -1 : e.Quality;
 	}

Pinta.Core/Classes/Document.cs

@@ -33,7 +33,7 @@ namespace Pinta.Core;
 // somewhat arbitrary.  In general:
 // Document - Data about the image itself
 // Workspace - Data about Pinta's state for the image
-public class Document
+public sealed class Document
 {
 	private string display_name = string.Empty;
 	private Gio.File? file = null;
@@ -393,25 +393,19 @@ public bool Save (bool saveAs)
 	/// </summary>
 	public void SignalSurfaceCloned ()
 	{
-		if (LayerCloned != null) {
-			LayerCloned ();
-		}
+		LayerCloned?.Invoke ();
 	}
 	#endregion
 
-	#region Protected Methods
-	protected void OnIsDirtyChanged ()
+	private void OnIsDirtyChanged ()
 	{
-		if (IsDirtyChanged != null)
-			IsDirtyChanged (this, EventArgs.Empty);
+		IsDirtyChanged?.Invoke (this, EventArgs.Empty);
 	}
 
-	protected void OnRenamed ()
+	private void OnRenamed ()
 	{
-		if (Renamed != null)
-			Renamed (this, EventArgs.Empty);
+		Renamed?.Invoke (this, EventArgs.Empty);
 	}
-	#endregion
 
 	#region Private Methods
 	private void OnSelectionChanged ()

Pinta.Core/Classes/DocumentWorkspace.cs

@@ -303,8 +303,7 @@ public void ZoomToCanvasRectangle (RectangleD rect)
 	#region Private Methods
 	private void OnCanvasInvalidated (CanvasInvalidatedEventArgs e)
 	{
-		if (CanvasInvalidated != null)
-			CanvasInvalidated (this, e);
+		CanvasInvalidated?.Invoke (this, e);
 	}
 
 	public void OnViewSizeChanged ()

Pinta.Core/Classes/ObservableObject.cs

@@ -45,7 +45,6 @@ protected void SetValue<T> (string propertyName, ref T member, T value)
 
 	protected void FirePropertyChanged (string? propertyName)
 	{
-		if (PropertyChanged != null)
-			PropertyChanged (this, new PropertyChangedEventArgs (propertyName));
+		PropertyChanged?.Invoke (this, new PropertyChangedEventArgs (propertyName));
 	}
 }

Pinta.Core/Classes/Palette.cs

@@ -46,8 +46,7 @@ private Palette ()
 
 	private void OnPaletteChanged ()
 	{
-		if (PaletteChanged != null)
-			PaletteChanged (this, EventArgs.Empty);
+		PaletteChanged?.Invoke (this, EventArgs.Empty);
 	}
 
 	public int Count => colors.Count;

Pinta.Core/Classes/Re-editable/Text/TextEngine.cs

@@ -451,9 +451,7 @@ private static int UTF8OffsetToCharacterOffset (string s, int offset)
 
 	private void OnModified ()
 	{
-		EventHandler? handler = Modified;
-		if (handler != null)
-			handler (this, EventArgs.Empty);
+		Modified?.Invoke (this, EventArgs.Empty);
 	}
 
 	private void DeleteSelection ()

Pinta.Core/Effects/Histogram.cs

@@ -53,9 +53,7 @@ protected internal Histogram (int channels, int entries, ImmutableArray<ColorBgr
 	public event EventHandler? HistogramChanged;
 	protected void OnHistogramUpdated ()
 	{
-		if (HistogramChanged != null) {
-			HistogramChanged (this, EventArgs.Empty);
-		}
+		HistogramChanged?.Invoke (this, EventArgs.Empty);
 	}
 
 	protected readonly ImmutableArray<ColorBgra> visual_colors;

Pinta.Core/Managers/ChromeManager.cs

@@ -30,7 +30,7 @@
 
 namespace Pinta.Core;
 
-public class ChromeManager
+public sealed class ChromeManager
 {
 	private PointI last_canvas_cursor_point;
 	private bool main_window_busy;
@@ -164,19 +164,16 @@ public void LaunchSimpleEffectDialog (BaseEffect effect, IAddinLocalizer localiz
 		simple_effect_dialog_handler (effect, localizer);
 	}
 	#endregion
-	#region Protected Methods
-	protected void OnLastCanvasCursorPointChanged ()
+
+	private void OnLastCanvasCursorPointChanged ()
 	{
-		if (LastCanvasCursorPointChanged != null)
-			LastCanvasCursorPointChanged (this, EventArgs.Empty);
+		LastCanvasCursorPointChanged?.Invoke (this, EventArgs.Empty);
 	}
 
-	protected void OnStatusBarTextChanged (string text)
+	private void OnStatusBarTextChanged (string text)
 	{
-		if (StatusBarTextChanged != null)
-			StatusBarTextChanged (this, new TextChangedEventArgs (text));
+		StatusBarTextChanged?.Invoke (this, new TextChangedEventArgs (text));
 	}
-	#endregion
 
 	#region Public Events
 	public event EventHandler? LastCanvasCursorPointChanged;

Pinta.Core/Managers/LivePreviewManager.cs

@@ -108,9 +108,7 @@ public void Start (BaseEffect effect)
 		if (effect.EffectData != null)
 			effect.EffectData.PropertyChanged += EffectData_PropertyChanged;
 
-		if (Started != null) {
-			Started (this, new LivePreviewStartedEventArgs ());
-		}
+		Started?.Invoke (this, new LivePreviewStartedEventArgs ());
 
 		var settings = new AsyncEffectRenderer.Settings () {
 			ThreadCount = PintaCore.System.RenderThreads,
@@ -305,9 +303,7 @@ void FireLivePreviewEndedEvent (RenderStatus status, Exception? ex)
 	void FireLivePreviewRenderUpdatedEvent (double progress, RectangleI bounds)
 	{
 
-		if (RenderUpdated != null) {
-			RenderUpdated (this, new LivePreviewRenderUpdatedEventArgs (progress, bounds));
-		}
+		RenderUpdated?.Invoke (this, new LivePreviewRenderUpdatedEventArgs (progress, bounds));
 	}
 
 	private void LivePreview_RenderUpdated (object? o, LivePreviewRenderUpdatedEventArgs args)

Pinta.Core/Managers/PaintBrushManager.cs

@@ -83,16 +83,12 @@ System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator ()
 
 	private void OnBrushAdded (BasePaintBrush brush)
 	{
-		var handler = BrushAdded;
-		if (handler != null)
-			handler (this, new BrushEventArgs (brush));
+		BrushAdded?.Invoke (this, new BrushEventArgs (brush));
 	}
 
 	private void OnBrushRemoved (BasePaintBrush brush)
 	{
-		var handler = BrushRemoved;
-		if (handler != null)
-			handler (this, new BrushEventArgs (brush));
+		BrushRemoved?.Invoke (this, new BrushEventArgs (brush));
 	}
 
 	private sealed class BrushSorter : Comparer<BasePaintBrush>

Pinta.Core/Managers/WorkspaceManager.cs

@@ -340,8 +340,7 @@ internal void SetActiveDocumentInternal (Document document)
 
 	private void OnActiveDocumentChanged (EventArgs e)
 	{
-		if (ActiveDocumentChanged != null)
-			ActiveDocumentChanged (this, EventArgs.Empty);
+		ActiveDocumentChanged?.Invoke (this, EventArgs.Empty);
 
 		OnSelectionChanged ();
 
@@ -354,20 +353,17 @@ private void OnDocumentCreated (DocumentEventArgs e)
 			OnSelectionChanged ();
 		};
 
-		if (DocumentCreated != null)
-			DocumentCreated (this, e);
+		DocumentCreated?.Invoke (this, e);
 	}
 
 	private void OnDocumentOpened (DocumentEventArgs e)
 	{
-		if (DocumentOpened != null)
-			DocumentOpened (this, e);
+		DocumentOpened?.Invoke (this, e);
 	}
 
 	private void OnDocumentClosed (DocumentEventArgs e)
 	{
-		if (DocumentClosed != null)
-			DocumentClosed (this, e);
+		DocumentClosed?.Invoke (this, e);
 	}
 
 	private void OnSelectionChanged ()

Pinta.Core/Widgets/ToolBarDropDownButton.cs

@@ -93,8 +93,7 @@ private void SetSelectedItem (ToolBarItem item)
 
 	private void OnSelectedItemChanged ()
 	{
-		if (SelectedItemChanged != null)
-			SelectedItemChanged (this, EventArgs.Empty);
+		SelectedItemChanged?.Invoke (this, EventArgs.Empty);
 	}
 
 	public event EventHandler? SelectedItemChanged;

Pinta.Gui.Widgets/Widgets/PointPickerGraphic.cs

@@ -30,7 +30,7 @@
 
 namespace Pinta.Gui.Widgets;
 
-public class PointPickerGraphic : Gtk.DrawingArea
+public sealed class PointPickerGraphic : Gtk.DrawingArea
 {
 	private ImageSurface? thumbnail;
 	private PointI position;
@@ -138,11 +138,9 @@ private RectangleI GetDrawBounds ()
 	#region Public Events
 	public event EventHandler? PositionChanged;
 
-	protected virtual void OnPositionChange ()
+	private void OnPositionChange ()
 	{
-		if (PositionChanged != null) {
-			PositionChanged (this, EventArgs.Empty);
-		}
+		PositionChanged?.Invoke (this, EventArgs.Empty);
 	}
 	#endregion