Add VisibleWhen and EnabledWhen attributes to SimpleEffectDialog (#1960)

* add VisibleWhenAttribute and EnabledWhenAttribute to DialogAttributes
This allows attributes in SimpleEffectDialog to automatically set their enabled state/visibility based on a condition

* Retrofit effects with VisibleWhen

Author: Matthieu-LAURENT39

CHANGELOG.md

@@ -7,12 +7,14 @@ Thanks to the following contributors who worked on this release:
 - @cameronwhite
 - @Lehonti
 - @spaghetti22
+- @Matthieu-LAURENT39
 
 ### Added
 - The splatter brush now allows the minimum and maximum splatter size to be configured separately from the brush width
 - The status bar color palette now supports Ctrl+clicking to edit a color, in addition to middle clicking (#1436)
 
 ### Changed
+- Effect dialogs now hide options that are not currently relevant (#1960)
 
 ### Fixed
 - Fixed a bug where duplicate submenus could be produced by add-ins with effect categories that were not translated (#1933, #1935)

Pinta.Core/Classes/DialogAttributes.cs

@@ -75,3 +75,28 @@ public sealed class StaticListAttribute : Attribute
 
 	public string DictionaryName { get; set; }
 }
+
+/// <summary>
+/// Attribute for controlling the visibility of a control based on a condition.
+/// The control will be hidden when the condition evaluates to false.
+/// </summary>
+[AttributeUsage (AttributeTargets.Field | AttributeTargets.Property, Inherited = false, AllowMultiple = false)]
+public sealed class VisibleWhenAttribute : Attribute
+{
+	public VisibleWhenAttribute (string conditionMethodName) => ConditionMethodName = conditionMethodName;
+
+	public string ConditionMethodName { get; }
+}
+
+/// <summary>
+/// Attribute for controlling the enabled state of a control based on a condition.
+/// The control will be disabled when the condition evaluates to false.
+/// </summary>
+[AttributeUsage (AttributeTargets.Field | AttributeTargets.Property, Inherited = false, AllowMultiple = false)]
+public sealed class EnabledWhenAttribute : Attribute
+{
+	public EnabledWhenAttribute (string conditionMethodName) => ConditionMethodName = conditionMethodName;
+
+	public string ConditionMethodName { get; }
+}
+

Pinta.Effects/Effects/CellsEffect.cs

@@ -181,9 +181,11 @@ public sealed class CellsData : EffectData
 		public ColorSchemeSource ColorSchemeSource { get; set; } = ColorSchemeSource.PresetGradient;
 
 		[Caption ("Color Scheme")]
+		[VisibleWhen (nameof (ShowColorScheme))]
 		public PresetGradients ColorScheme { get; set; } = PresetGradients.BlackAndWhite;
 
 		[Caption ("Random Color Scheme Seed")]
+		[VisibleWhen (nameof (ShowColorSchemeSeed))]
 		public RandomSeed ColorSchemeSeed { get; set; } = new (0);
 
 		[Caption ("Reverse Color Scheme")]
@@ -195,5 +197,11 @@ public sealed class CellsData : EffectData
 		[Caption ("Quality")]
 		[MinimumValue (1), MaximumValue (4)]
 		public int Quality { get; set; } = 3;
+
+		[Skip]
+		public bool ShowColorScheme => ColorSchemeSource == ColorSchemeSource.PresetGradient;
+
+		[Skip]
+		public bool ShowColorSchemeSeed => ColorSchemeSource == ColorSchemeSource.Random;
 	}
 }

Pinta.Effects/Effects/CloudsEffect.cs

@@ -146,12 +146,20 @@ public sealed class CloudsData : EffectData
 		public ColorSchemeSource ColorSchemeSource { get; set; } = ColorSchemeSource.SelectedColors;
 
 		[Caption ("Color Scheme")]
+		[VisibleWhen (nameof (ShowColorScheme))]
 		public PresetGradients ColorScheme { get; set; } = PresetGradients.BeautifulItaly;
 
 		[Caption ("Random Color Scheme Seed")]
+		[VisibleWhen (nameof (ShowColorSchemeSeed))]
 		public RandomSeed ColorSchemeSeed { get; set; } = new (0);
 
 		[Caption ("Reverse Color Scheme")]
 		public bool ReverseColorScheme { get; set; } = false;
+
+		[Skip]
+		public bool ShowColorScheme => ColorSchemeSource == ColorSchemeSource.PresetGradient;
+
+		[Skip]
+		public bool ShowColorSchemeSeed => ColorSchemeSource == ColorSchemeSource.Random;
 	}
 }

Pinta.Effects/Effects/JuliaFractalEffect.cs

@@ -156,15 +156,23 @@ public sealed class JuliaFractalData : EffectData
 		public ColorSchemeSource ColorSchemeSource { get; set; } = ColorSchemeSource.PresetGradient;
 
 		[Caption ("Color Scheme")]
+		[VisibleWhen (nameof (ShowColorScheme))]
 		public PresetGradients ColorScheme { get; set; } = PresetGradients.Bonfire;
 
 		[Caption ("Random Color Scheme Seed")]
+		[VisibleWhen (nameof (ShowColorSchemeSeed))]
 		public RandomSeed ColorSchemeSeed { get; set; } = new (0);
 
 		[Caption ("Reverse Color Scheme")]
 		public bool ReverseColorScheme { get; set; } = false;
 
 		[Caption ("Angle")]
 		public DegreesAngle Angle { get; set; } = new (0);
+
+		[Skip]
+		public bool ShowColorScheme => ColorSchemeSource == ColorSchemeSource.PresetGradient;
+
+		[Skip]
+		public bool ShowColorSchemeSeed => ColorSchemeSource == ColorSchemeSource.Random;
 	}
 }

Pinta.Effects/Effects/MandelbrotFractalEffect.cs

@@ -172,15 +172,23 @@ public sealed class MandelbrotFractalData : EffectData
 		public ColorSchemeSource ColorSchemeSource { get; set; } = ColorSchemeSource.PresetGradient;
 
 		[Caption ("Color Scheme")]
+		[VisibleWhen (nameof (ShowColorScheme))]
 		public PresetGradients ColorScheme { get; set; } = PresetGradients.Electric;
 
 		[Caption ("Random Color Scheme Seed")]
+		[VisibleWhen (nameof (ShowColorSchemeSeed))]
 		public RandomSeed ColorSchemeSeed { get; set; } = new (0);
 
 		[Caption ("Reverse Color Scheme")]
 		public bool ReverseColorScheme { get; set; } = false;
 
 		[Caption ("Invert Colors")]
 		public bool InvertColors { get; set; } = false;
+
+		[Skip]
+		public bool ShowColorScheme => ColorSchemeSource == ColorSchemeSource.PresetGradient;
+
+		[Skip]
+		public bool ShowColorSchemeSeed => ColorSchemeSource == ColorSchemeSource.Random;
 	}
 }

Pinta.Effects/Effects/VoronoiDiagramEffect.cs

@@ -202,21 +202,30 @@ public sealed class VoronoiDiagramData : EffectData
 		public PointArrangement PointArrangement { get; set; } = PointArrangement.Random;
 
 		[Caption ("Random Point Locations")]
+		[VisibleWhen (nameof (ShowRandomPointLocation))]
 		public RandomSeed RandomPointLocations { get; set; } = new (0);
 
 		[Caption ("Show Points")]
 		public bool ShowPoints { get; set; } = false;
 
 		[Caption ("Point Size")]
 		[MinimumValue (1), MaximumValue (16), IncrementValue (1)]
+		[VisibleWhen (nameof (ShowPointConfig))]
 		public double PointSize { get; set; } = 4;
 
 		[Caption ("Point Color")]
+		[VisibleWhen (nameof (ShowPointConfig))]
 		public Color PointColor { get; set; } = Color.Black;
 
 		[Caption ("Quality")]
 		[MinimumValue (1), MaximumValue (4)]
 		public int Quality { get; set; } = 3;
+
+		[Skip]
+		public bool ShowRandomPointLocation => PointArrangement == PointArrangement.Random;
+
+		[Skip]
+		public bool ShowPointConfig => ShowPoints;
 	}
 
 	public enum ColorSorting

Pinta.Gui.Widgets/Dialogs/ReflectionHelper.cs

@@ -20,4 +20,41 @@ internal static class ReflectionHelper
 		else
 			throw new ArgumentException ($"Member \'{name}\' does not exist");
 	}
+
+	/// <summary>
+	/// Evaluates a condition from a property or method of an object.
+	/// </summary>
+	/// <param name="source">The object containing the property or method.</param>
+	/// <param name="methodName">The name of the property or method to evaluate.</param>
+	/// <returns>The boolean result of the property or method.</returns>
+	public static bool EvaluateCondition (object source, string methodName)
+		=> CreateConditionDelegate (source, methodName) ();
+
+	/// <summary>
+	/// Creates a delegate for evaluating a condition from a property or method of an object.
+	/// This avoids needing to redo reflection lookups when the condition needs to be evaluated frequently.
+	/// </summary>
+	/// <param name="source">The object containing the property or method.</param>
+	/// <param name="methodName">The name of the property or method to evaluate.</param>
+	/// <returns>A delegate that evaluates the condition, giving the boolean result of the property or method.</returns>
+	public static Func<bool> CreateConditionDelegate (object source, string methodName)
+	{
+		Type type = source.GetType ();
+
+		// Try to find a property first
+		PropertyInfo? property = type.GetProperty (methodName, BindingFlags.Public | BindingFlags.Instance);
+		if (property is not null && property.PropertyType == typeof (bool)) {
+			MethodInfo? getter = property.GetGetMethod ();
+			if (getter is not null) {
+				return (Func<bool>) getter.CreateDelegate (typeof (Func<bool>), source);
+			}
+		}
+		// If we couldn't find a property, try to find a method
+		MethodInfo? method = type.GetMethod (methodName, BindingFlags.Public | BindingFlags.Instance, null, Type.EmptyTypes, null);
+		if (method is not null && method.ReturnType == typeof (bool)) {
+			return (Func<bool>) method.CreateDelegate (typeof (Func<bool>), source);
+		}
+
+		throw new ArgumentException ($"Member \'{methodName}\' is not a boolean property or method");
+	}
 }

Pinta.Gui.Widgets/Dialogs/SimpleEffectDialog.cs

@@ -48,6 +48,17 @@ public sealed class SimpleEffectDialog : Gtk.Dialog
 	private delegate bool TimeoutHandler ();
 	TimeoutHandler? timeout_func;
 
+	private readonly EffectData effect_data;
+
+	// Track widgets with conditional visibility/enabled, so we can update
+	// them when the effect data changes
+	private sealed record ConditionalWidget (
+		Gtk.Widget Widget,
+		Func<bool>? VisibleWhenDelegate,
+		Func<bool>? EnabledWhenDelegate
+	);
+	private readonly List<ConditionalWidget> conditional_widgets = new ();
+
 	/// Since this dialog is used by add-ins, the IAddinLocalizer allows for translations to be
 	/// fetched from the appropriate place.
 	/// </param>
@@ -82,6 +93,9 @@ public SimpleEffectDialog (
 			contentAreaBox.Append (widget);
 
 		OnClose += (_, _) => HandleClose ();
+
+		// Keep reference to effect data, so it can be used for handling conditional widgets
+		effect_data = effectData;
 	}
 
 	/// <summary>
@@ -132,8 +146,8 @@ private void HandleClose ()
 			.GetMembers ()
 			.Where (IsInstanceFieldOrProperty)
 			.Where (IsCustomProperty)
+			.Where (member => !member.GetCustomAttributes<SkipAttribute> (false).Any ())
 			.Select (CreateSettings)
-			.Where (settings => !settings.skip)
 			.Select (settings => GenerateWidgetsForMember (settings, effectData, localizer, workspace))
 			.SelectMany (widgets => widgets);
 
@@ -160,7 +174,9 @@ private sealed record MemberSettings (
 		MemberReflector reflector,
 		string caption,
 		string? hint,
-		bool skip);
+		string? visibleWhenMethodName,
+		string? enabledWhenMethodName
+	);
 
 	private static MemberSettings CreateSettings (MemberInfo memberInfo)
 	{
@@ -172,11 +188,24 @@ private static MemberSettings CreateSettings (MemberInfo memberInfo)
 			.Select (h => h.Caption)
 			.FirstOrDefault ();
 
+		string? visibleConditionMethodName =
+			reflector.Attributes
+			.OfType<VisibleWhenAttribute> ()
+			.Select (v => v.ConditionMethodName)
+			.FirstOrDefault ();
+
+		string? enabledConditionMethodName =
+			reflector.Attributes
+			.OfType<EnabledWhenAttribute> ()
+			.Select (e => e.ConditionMethodName)
+			.FirstOrDefault ();
+
 		return new (
 			reflector: reflector,
 			caption: caption ?? MakeCaption (memberInfo.Name),
 			hint: reflector.Attributes.OfType<HintAttribute> ().Select (h => h.Hint).FirstOrDefault (),
-			skip: reflector.Attributes.OfType<SkipAttribute> ().Any ());
+			visibleWhenMethodName: visibleConditionMethodName,
+			enabledWhenMethodName: enabledConditionMethodName);
 	}
 
 	private static string MakeCaption (string name)
@@ -209,6 +238,19 @@ static IEnumerable<char> GenerateCharacters (string name)
 		}
 	}
 
+	/// <summary>
+	/// Updates all widgets with conditional attributes.
+	/// </summary>
+	private void UpdateConditionalWidgets (EffectData effectData)
+	{
+		foreach (var widget in conditional_widgets) {
+			if (widget.VisibleWhenDelegate is not null)
+				widget.Widget.Visible = widget.VisibleWhenDelegate ();
+
+			if (widget.EnabledWhenDelegate is not null)
+				widget.Widget.Sensitive = widget.EnabledWhenDelegate ();
+		}
+	}
 	private IEnumerable<Gtk.Widget> GenerateWidgetsForMember (
 		MemberSettings settings,
 		EffectData effectData,
@@ -217,8 +259,36 @@ static IEnumerable<char> GenerateCharacters (string name)
 	{
 		WidgetFactory? widgetFactory = GetWidgetFactory (settings);
 
-		if (widgetFactory is not null)
-			yield return widgetFactory (localizer.GetString (settings.caption), effectData, settings, workspace);
+		if (widgetFactory is not null) {
+			Gtk.Widget widget = widgetFactory (localizer.GetString (settings.caption), effectData, settings, workspace);
+
+			// Keep a reference to widget if it has conditional attributes so we can update it later
+			if (settings.visibleWhenMethodName is not null || settings.enabledWhenMethodName is not null) {
+
+				// Create delegates for condition evaluation (do reflection once, not on every update)
+				Func<bool>? visibleDelegate = settings.visibleWhenMethodName is not null
+					? ReflectionHelper.CreateConditionDelegate (effectData, settings.visibleWhenMethodName)
+					: null;
+
+				Func<bool>? enabledDelegate = settings.enabledWhenMethodName is not null
+					? ReflectionHelper.CreateConditionDelegate (effectData, settings.enabledWhenMethodName)
+					: null;
+
+				// Apply the initial state
+				if (visibleDelegate is not null)
+					widget.Visible = visibleDelegate ();
+
+				if (enabledDelegate is not null)
+					widget.Sensitive = enabledDelegate ();
+
+				conditional_widgets.Add (new ConditionalWidget (
+					widget,
+					visibleDelegate,
+					enabledDelegate)
+				);
+			}
+			yield return widget;
+		}
 
 		if (settings.hint != null)
 			yield return CreateHintLabel (localizer.GetString (settings.hint));
@@ -530,6 +600,9 @@ private void SetAndNotify (MemberReflector reflector, object o, object val)
 	{
 		reflector.SetValue (o, val);
 		EffectDataChanged?.Invoke (this, new PropertyChangedEventArgs (reflector.OriginalMemberInfo.Name));
+
+		// Update conditional widgets when any property changes
+		UpdateConditionalWidgets (effect_data);
 	}
 
 	private Gtk.Widget CreateSeed (