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astodolski
11th September 2013, 21:32
I've seen a few examples of TWAIN using Qt. What I don't see is how the DS is created in Qt and yet the UI lives outside of QApplication. I would like to use a different TWAIN application that calls the Qt DS - if that makes sense.

ChrisW67
12th September 2013, 07:38
There is no out-of-the box support for TWAIN in Qt.

You can use TWAIN data source manager for Windows or Linux by building the library using your C++ tool chain (nothing to do with Qt) and then linking your Qt application to the library using the documented qmake PRO file entries (INCLUDEPATH and LIBS).

The "DS" driver files that the TWAIN library uses have nothing all to do with Qt: they come from device manufacturers.

astodolski
12th September 2013, 15:07
There is no out-of-the box support for TWAIN in Qt.

You can use TWAIN data source manager for Windows or Linux by building the library using your C++ tool chain (nothing to do with Qt) and then linking your Qt application to the library using the documented qmake PRO file entries (INCLUDEPATH and LIBS).

The "DS" driver files that the TWAIN library uses have nothing all to do with Qt: they come from device manufacturers.

Hi, I understand that there is not out-of-the-box support for TWAIN in Qt. I also understand how the data source (DS) is created. What I am trying to determine is how a DS that displays a UI can live outside of QApplication. You see the application i.e. Scanner application or whatever calls a dialog that is within the DS. Everything I know about Qt is that any widget lives as part of a process that is owned by QApplication. The "application" can be anything that conforms to the TWAIN consortium spec. It may be anything other than a Qt application.

Hope that is clearer.

Thanks

ChrisW67
13th September 2013, 00:00
Any UI that the TWAIN driver creates has nothing to do with the UI that the host application is providing (Qt or not) other than on Windows where the data source UI window may be parented to an application window handle (i.e. not a QObject style ownership). That UI is created using the relevant native Windows or UNIX APIs and libraries.

So what is the question?

astodolski
19th November 2013, 22:31
Any UI that the TWAIN driver creates has nothing to do with the UI that the host application is providing (Qt or not) other than on Windows where the data source UI window may be parented to an application window handle (i.e. not a QObject style ownership). That UI is created using the relevant native Windows or UNIX APIs and libraries.

So what is the question?

I've update the issue in this (http://www.qtcentre.org/threads/56958-TWAIN-DLL-that-spawns-a-thread-that-creates-a-GUI-works-on-Qt-4-8-died-on-Qt-5-1-1?p=254490#post254490) thread.