Handy helper function for FM² SupportsPlatformService

With Firemonkey 2 (FM²) which was introduced with Delphi XE3 the global variable Platform was refactured to a kind of service registry. You acquire a specific service which may or may not be available on your current platform via

TPlatformServices.Current.SupportsPlatformService(ServiceGUID, ServiceInterface)

This function returns True if the service is available and an interface reference to that service.

The Problem

The returned interface is an IInterface and not the type of the requested service. To set the clipboard content you need to write something like this

var
  ServiceIntf: IInterface;
...
if TPlatformServices.Current.SupportsPlatformService(IFMXClipboardService, ServiceIntf) then
  (ServiceIntf as IFMXClipboardService).SetClipboard('Hello');

Handy Helper

How about simply writing that:

var
  Service: IFMXClipboardService;
...
  if SupportsPlatformService(IFMXClipboardService, Service) then
    Service.SetClipboard('Hello');

this is exactly what following unit provides:

unit FMX.Platform.Tools;

interface

function SupportsPlatformService(const ServiceGUID: TGUID; out Service): Boolean;

implementation

uses
  FMX.Platform;

function SupportsPlatformService(const ServiceGUID: TGUID; out Service): Boolean;
var
  ServiceIntf: IInterface;
begin
  Result := TPlatformServices.Current.SupportsPlatformService(ServiceGUID, ServiceIntf);
  if Result then
    ServiceIntf.QueryInterface(ServiceGUID, Service) else
    IInterface(Service) := nil;
end;

end.