Dave Nottage

I'll have to check mstsc and RDP-session after the weekend, but the others are 64-bit. Regardless, the DLL succeeds in enumerating the sources, the scanning progress dialog shows, and it completes the scan; it is only when it reaches the ReadNative method and calls GlobalLock that there's an issue - why would all that comes before it succeed? Yes, it's non-zero.

Not on the remote machine no, since it does not have the scanner connected; the local machine does, where the RDS DLL resides. In this call, rc can be one of TWRC_XFERDONE, TWRC_CANCEL, or one of the error values. In this case, it is returning TWRC_XFERDONE (which is why it proceeds to the ReadNative call, where the error occurs, as per one of my earlier messages) so one would hope that it is returning a valid value for hNative. As far as GlobalLock is concerned, it apparently is not.

The TOSDevice record in this unit: https://github.com/DelphiWorlds/KastriFree/blob/master/Core/DW.OSDevice.pas Has a ShowFilesInFolder method, which "re-routes" to the respective platforms, namely macOS and Windows. For macOS: https://github.com/DelphiWorlds/KastriFree/blob/master/Core/DW.OSDevice.Mac.pas For Windows: https://github.com/DelphiWorlds/KastriFree/blob/master/Core/DW.OSDevice.Win.pas

That is correct. This is what I mean: https://docs.microsoft.com/en-us/windows/win32/termserv/virtual-channel-client-dll So yes, RDS; I'm just used to the other terminology. As above, the DLL is on the same machine as the Twain driver. RDS loads the DLL when a session is started to the remote application, which communicates to the virtual channel client DLL via RDS. The remote application notifies the virtual channel to scan an image, and the DLL makes calls via the Delphi Twain code to enumerate the sources, and start scanning an image. The scanning "in progress" dialog shows OK, however the code fails in TTwainSource.ReadNative, as described earlier. The identical code to allow the user to select the source and start the scan works in a DLL loaded by a test app; it fails in the virtual channel client (RDS) DLL. I just hoped someone might know why there's a difference, because debugging isn't telling me anything other than Windows claiming that the handle is invalid.

Well, it has now come "off the shelf", however not so good news: I'm now unable to make it receive on anything other than Windows (tried iOS, macOS and Android). Sending works from any platform. I swear it was all working before. In any event, I've now made it public, here: https://github.com/DelphiWorlds/Multicaster

It came from this call in the TTwainSource.TransferImages method: rc := Owner.TwainProc(AppInfo, @Structure, DG_IMAGE, DAT_IMAGENATIVEXFER, MSG_GET, @hNative) (TwainProc is the method exported by the Twain DLL) The more pertinent question is: why does it return a valid handle in a DLL that is not loaded by WTS, and why is it apparently invalid in a DLL loaded by WTS? I figured there might be something else I need to do to ensure that it returns a valid handle in WTS.

I discovered that it is throwing an AV at this part of TTwainSource.ReadNative: DibInfo := GlobalLock(Handle); ColorTableSize := (DibNumColors(DibInfo) * SizeOf(RGBQUAD)); // <---- AV here when it calls DibNumColors, as DibInfo is nil The code is inside a DLL written for Windows Terminal Services. The same code works fine in a DLL that is just loaded via a plain application, so perhaps it has something to with WTS? If I call SysErrorMessage(GetLastError) after the GlobalLock, the message is: The handle is invalid. The value for Handle is non-zero.

Instead of using Edit Custom Style for every component that we want a background color on, I came up with some code similar to this: type TEditEx = class(TEdit) private FColor: TAlphaColor; function GetBackgroundRectangle: TRectangle; procedure InternalSetColor(const Value: TAlphaColor); procedure SetColor(const Value: TAlphaColor); protected procedure ApplyStyle; override; published property Color: TAlphaColor read FColor write SetColor; end; procedure TEditEx.ApplyStyle; begin inherited; InternalSetColor(FColor); end; function TEditEx.GetBackgroundRectangle: TRectangle; var LStyleObject: TFmxObject; I: Integer; begin Result := nil; LStyleObject := FindStyleResource('rect'); if LStyleObject = nil then begin LStyleObject := FindStyleResource('background'); if LStyleObject <> nil then begin Result := TRectangle.Create(LStyleObject); Result.StyleName := 'rect'; Result.Align := TAlignLayout.Contents; Result.HitTest := False; Result.Stroke.Kind := TBrushKind.None; Result.Fill.Color := TAlphaColorRec.Null; Result.Parent := LStyleObject; end; end else Result := TRectangle(LStyleObject); end; procedure TEditEx.InternalSetColor(const Value: TAlphaColor); var LRectangle: TRectangle; begin LRectangle := GetBackgroundRectangle; if LRectangle <> nil then begin FColor := Value; LRectangle.Fill.Color := FColor; end; end; procedure TEditEx.SetColor(const Value: TAlphaColor); begin NeedStyleLookup; ApplyStyleLookup; InternalSetColor(Value); end; A side-effect of this code is that the inner parts of the edit control can be selected in the Object Inspector, like this: Any ideas of what I've done wrong, and how to remedy it?

I'm guessing sometime close to next Wednesday: http://blog.marcocantu.com/blog/2019-july-whatsnew-1032-webinar.html

Delphi Rio 10.3.1, VCL. I was having problems with refactored code based on the original. I went back to the very original code and managed to make it work, so something must have gone awry in the refactor. Next time it is refactored there'll be incremental testing 🙂 Next issue is: when it is used in a DLL, the app locks up after the scan has completed.

..or not declare vars inline 🙂

I managed to make UDP multicast work to my satisfaction (with both IPv4 and IPv6) with Indy a while ago.. had to jump through a bunch of hoops to make it happen. My work has been "sitting on a shelf" waiting for funding for the project(s) it may be used in, but I could turn it into some building blocks for anyone who's interested. One of the things I had to overcome was the lack of multiple bindings in TIdIPMCastServer - a pretty basic omission. Others were: local address changes (because of one or more networks being unavailable etc), dealing with IPv6 only networks (a must for iOS), and discovering local addresses on Android (which Indy does not do yet, unless it has changed recently) I've tried a number of network libraries including ICS, but Indy is still the least painful to work with. Much kudos to Remy.

If there is a "Show expired certificates" menu item under the View menu in the Keychain Access app, please click it, and delete any expired certificates.

Which means it cannot find a matching certificate for the provisioning profile. Please ensure that the provisioning profile you are using actually *has* the iOS Distribution certificate assigned to it. To do this, go to: https://developer.apple.com/account/ Log in, go to Certificates, IDs and Profiles, select Profiles section, and select the profile for rexpressmanager (make sure it's actually an App Store profile), and check which certificate is assigned to it (bottom left of the info). If it's not an App Store profile, you'll need to create one.

I should have also asked what you mean by this, i.e. is there an error thrown in the IDE? If so, please give all the details. If not, at what stage is it a problem? Using Application Loader?