OPC UA examples use relative paths and assume in-source builds, thus do not work out-of-the-box when loaded in Qt Creator

The examples use relative paths to navigate from the executable's directory back to the source directory. These paths are only correct for in-source builds, not for shadow builds.

• The OPC UA Viewer example (https://doc.qt.io/qt-6/qtopcua-opcuaviewer-example.html ) tries to load and save certificates in the source folder

• The Water Pump examples (https://doc.qt.io/qt-6/qtopcua-waterpump-waterpump-qmlcpp-example.html, https://doc.qt.io/qt-6/qtopcua-waterpump-waterpump-qml-example.html ) try to launch the Simulation Server executable via a relative path.

In addition, the Windows-specific path building code in the OPC UA Viewer Example is wrong anyway:

Critical: Creating PKI path 'C:/Qt/Examples/Qt-6.4.1/opcua/build-opcuaviewer-Desktop_Qt_6_4_1_MSVC2019_64bit-Debug..//pki/trusted/certs': FAILED.

Suggestions

• Embed provided certificates in a QRC resource, to avoid loading them from the source folder.
• Save certificates somewhere using QStandardPaths or in PWD, to avoid writing files to the source folder.
• Just ask the user to manually run the Simulation Server before starting the client (like how the WebSocket examples do it: https://doc.qt.io/qt-6/qtwebsockets-examples.html ). Don't try to be programatically find the other executable.