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POUsing specific class type reference in Delphi attribute-constructor
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copied!<p>As Delphi cannot handle attributes on enum-values, I tried another approach. TMyEnum is my enum. Class TMyEnumLabelProvider provides the labels I need. I link the enum-type with an attribute to its labelprovider. This doesn't compile however. I cannot define the provider fully before referencing its classtype since it uses TMyEnum in one of its methods. </p> <pre><code>TEnumLabelProviderCallback = procedure(Context: TObject; Index: integer; const Name: string) of object; TEnumLabelProvider = class abstract public procedure Iterate(Context: TObject; Callback: TEnumLabelProviderCallback); virtual; abstract; end; TEnumLabelProviderClass = class of TEnumLabelProvider; TEnumLabelProviderAttribute = class(TCustomAttribute) private FProviderClass: TEnumLabelProviderClass; public constructor Create(ProviderClass: TEnumLabelProviderClass); property ProviderClass: TEnumLabelProviderClass read FProviderClass; end; TMyEnumLabelProvider = class; {$SCOPEDENUMS ON} [TEnumLabelProvider(TMyEnumLabelProvider)] TMyEnum = (MyEnum0, MyEnum1, MyEnum2); {$SCOPEDENUMS OFF} // This is where the compilation fails..... TMyEnumLabelProvider = class(TEnumLabelProvider) public class function GetLabel(MyEnum: TMyEnum): string; procedure Iterate(Context: TObject; Callback: TEnumLabelProviderCallback); override; end; </code></pre> <p>Any ideas on how to do this properly. For now I workaround by declaring GetLabel(MyEnum: integer), but obviously I prefer being type strict.</p> <p>Thanks in advance.</p>

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