Bugfix - OnChanged method refactored to allow BindingPropertyChangedD…

…elegate
rrmanzano · Apr 14, 2022 · 746ce2e · 746ce2e
1 parent ba73b7b
commit 746ce2e
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Showing 5 changed files with 137 additions and 16 deletions.
diff --git a/src/Maui.BindableProperty.Generator/Core/BindableProperty/AutoBindablePropertyGenerator.cs b/src/Maui.BindableProperty.Generator/Core/BindableProperty/AutoBindablePropertyGenerator.cs
@@ -2,13 +2,16 @@
 using Microsoft.CodeAnalysis.Text;
 using System.Text;
 using Maui.BindableProperty.Generator.Helpers;
+using Maui.BindableProperty.Generator.Core.BindableProperty.Implementation;
 
 namespace Maui.BindableProperty.Generator.Core.BindableProperty
 {
 
     [Generator]
     public class AutoBindablePropertyGenerator : ISourceGenerator
     {
+        private TypedConstant NameProperty { get; set; }
+        private readonly List<IImplementation> CustomImplementations = new() { new PropertyChanged() };
 
         private const string attributeText = @"
         using System;
@@ -65,44 +68,71 @@ private void ProcessBindableProperty(CodeWriter w, IFieldSymbol fieldSymbol, ISy
             var fieldName = fieldSymbol.Name;
             var fieldType = fieldSymbol.Type;
 
-            // Get the AutoNotify attribute from the field, and any associated data
-            var attributeData = fieldSymbol.GetAttributes().Single(ad => ad.AttributeClass.Equals(attributeSymbol, SymbolEqualityComparer.Default));
-            TypedConstant GetValue(string key)
-            {
-                return attributeData.NamedArguments.SingleOrDefault(kvp => kvp.Key == key).Value;
-            }
-
-            var overridenNameProperty = GetValue("PropertyName");
-            var overridenOnChanged = GetValue("OnChanged");
+            this.InitializeAttrProperties(fieldSymbol, attributeSymbol, classSymbol);
 
-            var propertyName = this.ChooseName(fieldName, overridenNameProperty);
+            var propertyName = this.ChooseName(fieldName, this.NameProperty);
             if (propertyName?.Length == 0 || propertyName == fieldName)
             {
                 // TODO: issue a diagnostic that we can't process this field
                 return;
             }
 
             var bindablePropertyName = $@"{propertyName}Property";
+            var customParameters = this.ProcessBindableParameters();
             w._(AutoBindableConstants.AttributeGeneratedCodeString);
-            w._($@"public static readonly Microsoft.Maui.Controls.BindableProperty {bindablePropertyName} = Microsoft.Maui.Controls.BindableProperty.Create(nameof({propertyName}), typeof({fieldType}), typeof({classSymbol.Name}), default({fieldType}));");
+            w._($@"public static readonly Microsoft.Maui.Controls.BindableProperty {bindablePropertyName} = Microsoft.Maui.Controls.BindableProperty.Create(nameof({propertyName}), typeof({fieldType}), typeof({classSymbol.Name}), default({fieldType}){customParameters});");
             w._(AutoBindableConstants.AttributeGeneratedCodeString);
             using (w.B(@$"public {fieldType} {propertyName}"))
             {
                 w._($@"get => ({fieldType})GetValue({bindablePropertyName});");
-                if (!overridenOnChanged.IsNull)
+                if (this.ExistsBodySetter())
                 {
-                    var method = overridenOnChanged.Value?.ToString();
                     using (w.B(@$"set"))
                     {
-                        w._($@"SetValue({bindablePropertyName}, value);",
-                            $@"this.{method}(value);");
+                        w._($@"SetValue({bindablePropertyName}, value);");
+                        this.ProcessBodyStter(w);
                     }
                 }
                 else
                 {
                     w._($@"set => SetValue({bindablePropertyName}, value);");
                 }
             }
+
+            this.ProcessImplementationLogic(w);
+        }
+
+
+        private void InitializeAttrProperties(IFieldSymbol fieldSymbol, ISymbol attributeSymbol, INamedTypeSymbol classSymbol)
+        {
+            this.NameProperty = fieldSymbol.GetTypedConstant(attributeSymbol, "PropertyName");
+            this.CustomImplementations.ForEach(i => i.Initialize(this.NameProperty, fieldSymbol, attributeSymbol, classSymbol));
+        }
+
+        private string ProcessBindableParameters()
+        {
+            var parameters = this.CustomImplementations
+                                    .Select(i => i.ProcessBindableParameters())
+                                    .Where(x => !string.IsNullOrEmpty(x));
+
+            return parameters.Any() ? $@", { string.Join(", ", parameters) }" : string.Empty;
+        }
+
+        private void ProcessBodyStter(CodeWriter w)
+        {
+            this.CustomImplementations
+                    .ForEach(i => i.ProcessBodyStter(w));
+        }
+
+        private void ProcessImplementationLogic(CodeWriter w)
+        {
+            this.CustomImplementations
+                .ForEach(i => i.ProcessImplementationLogic(w));
+        }
+
+        private bool ExistsBodySetter()
+        {
+            return this.CustomImplementations.Any(i => i.Implemented());
         }
 
         private string ChooseName(string fieldName, TypedConstant overridenNameOpt)

diff --git a/src/Maui.BindableProperty.Generator/Core/BindableProperty/Implementation/IImplementation.cs b/src/Maui.BindableProperty.Generator/Core/BindableProperty/Implementation/IImplementation.cs
@@ -0,0 +1,13 @@
+using Microsoft.CodeAnalysis;
+
+namespace Maui.BindableProperty.Generator.Core.BindableProperty.Implementation
+{
+    public interface IImplementation
+    {
+        void Initialize(TypedConstant nameProperty, IFieldSymbol fieldSymbol, ISymbol attributeSymbol, INamedTypeSymbol classSymbol);
+        bool Implemented();
+        string ProcessBindableParameters();
+        void ProcessBodyStter(CodeWriter w);
+        void ProcessImplementationLogic(CodeWriter w);
+    }
+}
diff --git a/src/Maui.BindableProperty.Generator/Core/BindableProperty/Implementation/PropertyChanged.cs b/src/Maui.BindableProperty.Generator/Core/BindableProperty/Implementation/PropertyChanged.cs
@@ -0,0 +1,61 @@
+using Maui.BindableProperty.Generator.Helpers;
+using Microsoft.CodeAnalysis;
+
+namespace Maui.BindableProperty.Generator.Core.BindableProperty.Implementation
+{
+    public class PropertyChanged : IImplementation
+    {
+        private TypedConstant NameProperty { get; set; }
+        private TypedConstant OnChangedProperty { get; set; }
+        private IFieldSymbol FieldSymbol { get; set; }
+        private ISymbol AttributeSymbol { get; set; }
+        private INamedTypeSymbol ClassSymbol { get; set; }
+
+        public void Initialize(TypedConstant nameProperty, IFieldSymbol fieldSymbol, ISymbol attributeSymbol, INamedTypeSymbol classSymbol)
+        {
+            this.NameProperty = nameProperty;
+            this.OnChangedProperty = fieldSymbol.GetTypedConstant(attributeSymbol, "OnChanged");
+            this.FieldSymbol = fieldSymbol;
+            this.AttributeSymbol = attributeSymbol;
+            this.ClassSymbol = classSymbol;
+        }
+
+        public bool Implemented()
+        {
+            return !this.OnChangedProperty.IsNull;
+        }
+
+        public string ProcessBindableParameters()
+        {
+            if (!this.OnChangedProperty.IsNull)
+            {
+                var method = this.OnChangedProperty.Value?.ToString();
+                return $@"propertyChanged: __{method}";
+            }
+
+            return null;
+        }
+
+        public void ProcessBodyStter(CodeWriter w)
+        {
+            if (!this.OnChangedProperty.IsNull)
+            {
+                var method = this.OnChangedProperty.Value?.ToString();
+                w._($@"this.{method}(value);");
+            }
+        }
+
+        public void ProcessImplementationLogic(CodeWriter w)
+        {
+            if (!this.OnChangedProperty.IsNull)
+            {
+                var method = this.OnChangedProperty.Value?.ToString();
+                w._(AutoBindableConstants.AttributeGeneratedCodeString);
+                using (w.B(@$"public static void __{method}(Microsoft.Maui.Controls.BindableObject bindable, object oldValue, object newValue)"))
+                {
+                    w._($@"(({this.ClassSymbol.Name})bindable).{method}(({this.FieldSymbol.Type})newValue);");
+                }
+            }
+        }
+    }
+}
diff --git a/src/Maui.BindableProperty.Generator/Helpers/SymbolExtensions.cs b/src/Maui.BindableProperty.Generator/Helpers/SymbolExtensions.cs
@@ -0,0 +1,17 @@
+using Microsoft.CodeAnalysis;
+
+namespace Maui.BindableProperty.Generator.Helpers
+{
+    internal static class SymbolExtensions
+    {
+        public static TypedConstant GetTypedConstant(
+            this IFieldSymbol fieldSymbol,
+            ISymbol attributeSymbol,
+            string key)
+        {
+            // Get the AutoNotify attribute from the field, and any associated data
+            var attributeData = fieldSymbol.GetAttributes().Single(ad => ad.AttributeClass.Equals(attributeSymbol, SymbolEqualityComparer.Default));
+            return attributeData.NamedArguments.SingleOrDefault(kvp => kvp.Key == key).Value;
+        }
+    }
+}
diff --git a/src/Maui.BindableProperty.Generator/Maui.BindableProperty.Generator.csproj b/src/Maui.BindableProperty.Generator/Maui.BindableProperty.Generator.csproj
@@ -10,7 +10,7 @@
 		<Description>Source generator that automatically transforms fields into BindableProperties that can be used in MAUI</Description>
 		<PackageTags>MAUI;BindableProperty;Source Generator</PackageTags>
 		<PackageReadmeFile>README.md</PackageReadmeFile>
-		<VersionPrefix>0.4.0</VersionPrefix>
+		<VersionPrefix>0.4.1</VersionPrefix>
 		<PackageProjectUrl>https://github.com/rrmanzano/maui-bindableproperty-generator</PackageProjectUrl>
 		<RepositoryUrl>https://github.com/rrmanzano/maui-bindableproperty-generator</RepositoryUrl>
 		<PackageId>M.BindableProperty.Generator</PackageId>