[generator] Revert change to use auto-properties in EventArgs classes (#736)

In ee7afee, properties in generated EventArgs classes were changed
from regular properties:
int param1;
public int Param1 {
get { return param1; }
}
to instead emit auto-properties:
public int Param1 { get; }
However, this is technically a source breaking change, since users
could have hand written code that references the backing field.
Although the usage is likely rare, we have decided to revert the
auto-property change for compatibility reasons.

Author: jpobst

tests/generator-Tests/Unit-Tests/CodeGeneratorExpectedResults/Common/WriteDuplicateInterfaceEventArgs.txt

@@ -123,24 +123,37 @@ internal partial class AnimatorListenerInvoker : global::Java.Lang.Object, Anima
 
 // event args for java.code.AnimatorListener.OnAnimationEnd
 public partial class AnimationEndEventArgs : global::System.EventArgs {
+	bool handled;
+
+	public bool Handled {
+ get { return handled; }
+ set { handled = value; }
+	}
+
 	public AnimationEndEventArgs (bool handled, int param1)
 	{
- this.Handled = handled;
- this.Param1 = param1;
+ this.handled = handled;
+ this.param1 = param1;
+	}
+
+	int param1;
+
+	public int Param1 {
+ get { return param1; }
 	}
 
 	public AnimationEndEventArgs (bool handled, int param1, int param2)
 	{
- this.Handled = handled;
- this.Param1 = param1;
- this.Param2 = param2;
+ this.handled = handled;
+ this.param1 = param1;
+ this.param2 = param2;
 	}
 
-public bool Handled { get; set; }
+int param2;
 
-	public int Param1 { get; private set; }
-
-public int Param2 { get; private set; }
+	public int Param2 {
+ get { return param2; }
+	}
 
 }
 

tests/generator-Tests/expected.ji/GenericArguments/Com.Google.Android.Exoplayer.Drm.IExoMediaDrm.cs

@@ -123,22 +123,42 @@ public unsafe void OnEvent (global::Com.Google.Android.Exoplayer.Drm.IExoMediaDr
 publicpartialclassExoMediaDrmOnEventEventArgs:global::System.EventArgs{
 publicExoMediaDrmOnEventEventArgs(global::Com.Google.Android.Exoplayer.Drm.IExoMediaDrmp0,byte[]p1,intp2,intp3,byte[]p4)
 {
-this.P0=p0;
-this.P1=p1;
-this.P2=p2;
-this.P3=p3;
-this.P4=p4;
+this.p0=p0;
+this.p1=p1;
+this.p2=p2;
+this.p3=p3;
+this.p4=p4;
 }
 
-publicglobal::Com.Google.Android.Exoplayer.Drm.IExoMediaDrmP0{get;privateset;}
+global::Com.Google.Android.Exoplayer.Drm.IExoMediaDrmp0;
 
-publicbyte[]P1{get;privateset;}
+publicglobal::Com.Google.Android.Exoplayer.Drm.IExoMediaDrmP0{
+get{returnp0;}
+}
+
+byte[]p1;
+
+publicbyte[]P1{
+get{returnp1;}
+}
+
+intp2;
 
-publicintP2{get;privateset;}
+publicintP2{
+get{returnp2;}
+}
+
+intp3;
 
-publicintP3{get;privateset;}
+publicintP3{
+get{returnp3;}
+}
 
-publicbyte[]P4{get;privateset;}
+byte[]p4;
+
+publicbyte[]P4{
+get{returnp4;}
+}
 
 }
 

tools/generator/SourceWriters/InterfaceEventArgsClass.cs

@@ -18,18 +18,12 @@ public InterfaceEventArgsClass (InterfaceGen iface, Method method)
 IsPublic=true;
 IsPartial=true;
 
+UsePriorityOrder=true;
+
 Comments.Add($"// event args for {iface.JavaName}.{method.JavaName}");
 
-// Add: public bool Handled { get; set; }
 if(method.IsEventHandlerWithHandledProperty)
-Properties.Add(newPropertyWriter{
-Name="Handled",
-PropertyType=TypeReferenceWriter.Bool,
-IsPublic=true,
-HasGet=true,
-HasSet=true,
-IsAutoProperty=true
-});
+Properties.Add(newHandledProperty());
 }
 
 publicvoidAddMembersFromMethod(InterfaceGeniface,Methodmethod,CodeGenerationOptionsopt)
@@ -47,15 +41,15 @@ void AddConstructor (InterfaceGen iface, Method method, CodeGenerationOptions op
 
 if(method.IsEventHandlerWithHandledProperty){
 ctor.Parameters.Add(newMethodParameterWriter("handled",TypeReferenceWriter.Bool));
-ctor.Body.Add("this.Handled = handled;");
+ctor.Body.Add("this.handled = handled;");
 }
 
 foreach(varpinmethod.Parameters){
 if(p.IsSender)
 continue;
 
 ctor.Parameters.Add(newMethodParameterWriter(p.Name,newTypeReferenceWriter(opt.GetTypeReferenceName(p))));
-ctor.Body.Add($"this.{p.PropertyName} = {opt.GetSafeIdentifier(p.Name)};");
+ctor.Body.Add($"this.{opt.GetSafeIdentifier(p.Name)} = {opt.GetSafeIdentifier(p.Name)};");
 }
 
 Constructors.Add(ctor);
@@ -71,18 +65,47 @@ void AddProperties (Method method, CodeGenerationOptions opt)
 if(Properties.Any(prop =>prop.Name==p.PropertyName))
 continue;
 
+Fields.Add(newFieldWriter{
+Name=opt.GetSafeIdentifier(p.Name),
+Type=newTypeReferenceWriter(opt.GetTypeReferenceName(p))
+});
+
 varprop=newPropertyWriter{
 Name=p.PropertyName,
 PropertyType=newTypeReferenceWriter(opt.GetTypeReferenceName(p)),
 IsPublic=true,
-HasGet=true,
-HasSet=true,
-IsAutoProperty=true,
-AutoSetterVisibility=Visibility.Private
+HasGet=true
 };
 
+prop.GetBody.Add($"return {opt.GetSafeIdentifier(p.Name)};");
+
 Properties.Add(prop);
 }
 }
 }
+
+publicclassHandledProperty:PropertyWriter
+{
+publicHandledProperty()
+{
+Name="Handled";
+PropertyType=TypeReferenceWriter.Bool;
+
+IsPublic=true;
+
+HasGet=true;
+GetBody.Add("return handled;");
+
+HasSet=true;
+SetBody.Add("handled = value;");
+}
+
+publicoverridevoidWrite(CodeWriterwriter)
+{
+writer.WriteLine("bool handled;");
+writer.WriteLine();
+
+base.Write(writer);
+}
+}
 }