TECH TIP: How to Make a Data-Aware RB Component

1. Publish the DataPipeline and DataField properties. These are declared in the ancestor class TppPrintable (ppPrnabl.pas).
2. Override the public IsDataAware function from TppPrintable class to return True.
   
   Delphi/Pascal

   function TmyDBComponent.IsDataAware: Boolean; begin Result := True; end;

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   function TmyDBComponent.IsDataAware: Boolean; begin   Result := True;   end;

3. Override the public Notify method from the ancestor to redraw the design control.
   
   Delphi/Pascal

   procedure TmyDBComponent.Notify(aCommunicator: TppCommunicator; aOperation: TppOperationType); begin inherited Notify(aCommunicator, aOperation); if (aOperation in [ppopDataChange, ppopRemove]) and (pppcDesigning in DesignState) and not(Printing) then InvalidateDesignControl; end; {procedure, Notify}

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   procedure TmyDBComponent.Notify(aCommunicator: TppCommunicator; aOperation: TppOperationType); begin     inherited Notify(aCommunicator, aOperation);     if (aOperation in [ppopDataChange, ppopRemove]) and (pppcDesigning in DesignState) and not(Printing) then     InvalidateDesignControl;     end; {procedure, Notify}

4. Override SetDataField to also redraw the design control. It is a protected method of TppPrintable.
   
   Delphi/Pascal

   procedure TmyDBComponent.Notify(const Value: String); begin inherited SetDataField(Value); Notify(DataPipeline, ppopDataChange);

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   procedure TmyDBComponent.Notify(const Value: String); begin     inherited SetDataField(Value);     Notify(DataPipeline, ppopDataChange);