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Why shows error message when generating application release



  • I have the following problem, when generating the release of my application, it shows me this message, even though I add the libraries you need, that message still appears, also try using the windeployqt.exe and it does not work, any suggestion would be appreciated .

    I am using version 5.15.2 of qt

    3972227c-d42d-41f4-8423-dd3d3cb05988-image.png



  • Hello again friends, I was able to solve my problem, I was checking in the advanced configuration of the system and it happened that it had several values, in the PATH variable with paths to the Qt installation folder, so I deleted them all and with that I could solve my problem, thanks for your answers.

    now the problem is with respect to the database, I managed to generate the executable, add all the libraries you need, it happens that it does not show anything when I run it.

    e8231785-f45d-4939-9b10-6af4c62f6e20-image.png

    The application is already running, but the data is not displayed, which it queries from the DB.


  • Lifetime Qt Champion

    Hi,

    When exactly do you have that error ?
    Are you starting your application from Windows's explorer ?



  • @SGaist said in Why shows error message when generating application release:

    When exactly do you have that error ?
    Are you starting your application from Windows's explorer ?

    The message is displayed when I click on the executable, in the Windows Explorer, which is created with the QTCREATOR.

    The application is not executed from the Windows Explorer, even when you add the corresponding libraries



  • The error message is telling you that it does not have the proper libraries available in the enviornment the executable is running.

    Options:

    • There are (incorrect) Qt libraries on the system PATH found before those you intend.
    • Your libraries are from the wrong version of Qt (often this is because you have pulled the libs supporting Qt Creator rather than those you built against).
    • Your libraries are from the correct version of Qt but are the debug rather than release versions
    • There are no libraries to be found.

    The missing function should be in Qt5Core.dll library built with MingW.

    Please post the result of :

    • Windows command prompt TREE from the directory containing the EXE you are running
    • The value of PATH


  • Hello again friends, I was able to solve my problem, I was checking in the advanced configuration of the system and it happened that it had several values, in the PATH variable with paths to the Qt installation folder, so I deleted them all and with that I could solve my problem, thanks for your answers.

    now the problem is with respect to the database, I managed to generate the executable, add all the libraries you need, it happens that it does not show anything when I run it.

    e8231785-f45d-4939-9b10-6af4c62f6e20-image.png

    The application is already running, but the data is not displayed, which it queries from the DB.



  • QSqlDatabase::open() returns true?



  • Yes, the connection returns true, when I test it in Qt Creator everything is fine, but when I test it on another pc, the data is not shown.


  • Lifetime Qt Champion

    Did you properly deploy all dependencies ? Including the ones for the SQL driver you are using ?



  • This post is deleted!


  • @SGaist
    Of course, as you can see in the previous image that I publish, there are all the dependencies, those of the database and others that the application needs, which automatically adds windeployqt, and those that I add, manually such as:

    libpq.dll
    libcrypto-1_1-x64.dll
    libiconv-2.dll
    libintl-8.dll
    libssl-1_1-x64.dll.

    I am using PostgreSQL version 13.3 and Qt 5.15.2. Both 64-bit

    These libraries correspond to PostgreSQL, as I did my tests in Qt Creator, they work fine there, but when I create the exe and run from there, nothing happens.

    Even so, the data is not shown; And it doesn't occur to me what else it could be.

    Here run from the Qt Creator, the data is shown without problems, which does not happen when I deploy the application.
    74843d4c-81f7-4d16-b7f8-5932e0ca7829-image.png


  • Lifetime Qt Champion

    @lincoln said in Why shows error message when generating application release:

    And it doesn't occur to me what else it could be

    Set QT_DEBUG_PLUGINS to 1 before starting you app from terminal and put the output here.
    https://doc.qt.io/qt-5/debug.html



  • @jsulm Thanks for your answer, but I don't really know how to do what you tell me, thank you anyway.



  • @lincoln
    Use the forum Search for QT_DEBUG_PLUGINS. We don't want to answer the same question from many users over and over. It's also in the docs at Environment Variables Recognized by Qt. You need to read and act on these.


  • Lifetime Qt Champion

    @lincoln said in Why shows error message when generating application release:

    Here run from the Qt Creator, the data is shown without problems, which does not happen when I deploy the application.

    Do you run that deployed version on your machine or on a different machine ?



  • @SGaist First I tried it on my machine, and then I took it to a different one, where the Qt was not installed, and the same result.



  • @JonB ok, thanks


  • Lifetime Qt Champion

    Then the next step is to start your application from the command line with QT_DEBUG_PLUGINS set to 1 to see what is going on.



  • This post is deleted!


  • @SGaist ok thanks, i'll find out how to do that.



  • THIS IS A MESSAGE THAT IS DISPLAYED AFTER STARTING THE APP WITH QT_DEBUG_PLUGINS

    QFactoryLoader::QFactoryLoader() checking directory path "C:/Qt/6.1.2/mingw81_64/plugins/sqldrivers" ...
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/sqldrivers/qsqlite.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/sqldrivers/qsqlite.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QSqlDriverFactoryInterface",
    "MetaData": {
    "Keys": [
    "QSQLITE"
    ]
    },
    "archreq": 0,
    "className": "QSQLiteDriverPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("QSQLITE")
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/sqldrivers/qsqlodbc.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/sqldrivers/qsqlodbc.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QSqlDriverFactoryInterface",
    "MetaData": {
    "Keys": [
    "QODBC"
    ]
    },
    "archreq": 0,
    "className": "QODBCDriverPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("QODBC")
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/sqldrivers/qsqlpsql.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/sqldrivers/qsqlpsql.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QSqlDriverFactoryInterface",
    "MetaData": {
    "Keys": [
    "QPSQL"
    ]
    },
    "archreq": 0,
    "className": "QPSQLDriverPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("QPSQL")
    loaded library "C:/Qt/6.1.2/mingw81_64/plugins/sqldrivers/qsqlpsql.dll"
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Qt/6.1.2/mingw81_64/plugins/platforms" ...
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/platforms/qdirect2d.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/platforms/qdirect2d.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
    "Keys": [
    "direct2d"
    ]
    },
    "archreq": 0,
    "className": "QWindowsDirect2DIntegrationPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("direct2d")
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/platforms/qminimal.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/platforms/qminimal.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
    "Keys": [
    "minimal"
    ]
    },
    "archreq": 0,
    "className": "QMinimalIntegrationPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("minimal")
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/platforms/qoffscreen.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/platforms/qoffscreen.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
    "Keys": [
    "offscreen"
    ]
    },
    "archreq": 0,
    "className": "QOffscreenIntegrationPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("offscreen")
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/platforms/qwindows.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/platforms/qwindows.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
    "Keys": [
    "windows"
    ]
    },
    "archreq": 0,
    "className": "QWindowsIntegrationPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("windows")
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Users/USER/Downloads/build-monitoreo_xertek-Desktop_Qt_6_1_2_MinGW_64_bit-Release/release/platforms" ...
    loaded library "C:/Qt/6.1.2/mingw81_64/plugins/platforms/qwindows.dll"
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Qt/6.1.2/mingw81_64/plugins/platformthemes" ...
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Users/USER/Downloads/build-monitoreo_xertek-Desktop_Qt_6_1_2_MinGW_64_bit-Release/release/platformthemes" ...
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Qt/6.1.2/mingw81_64/plugins/styles" ...
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/styles/qwindowsvistastyle.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/styles/qwindowsvistastyle.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QStyleFactoryInterface",
    "MetaData": {
    "Keys": [
    "windowsvista"
    ]
    },
    "archreq": 0,
    "className": "QWindowsVistaStylePlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("windowsvista")
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Users/USER/Downloads/build-monitoreo_xertek-Desktop_Qt_6_1_2_MinGW_64_bit-Release/release/styles" ...
    loaded library "C:/Qt/6.1.2/mingw81_64/plugins/styles/qwindowsvistastyle.dll"
    QSqlDatabasePrivate::removeDatabase: connection 'qt_sql_default_connection' is still in use, all queries will cease to work.
    QSqlDatabasePrivate::addDatabase: duplicate connection name 'qt_sql_default_connection', old connection removed.
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Qt/6.1.2/mingw81_64/plugins/iconengines" ...
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/iconengines/qsvgicon.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/iconengines/qsvgicon.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QIconEngineFactoryInterface",
    "MetaData": {
    "Keys": [
    "svg",
    "svgz",
    "svg.gz"
    ]
    },
    "archreq": 0,
    "className": "QSvgIconPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("svg", "svgz", "svg.gz")
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Users/USER/Downloads/build-monitoreo_xertek-Desktop_Qt_6_1_2_MinGW_64_bit-Release/release/iconengines" ...
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Qt/6.1.2/mingw81_64/plugins/imageformats" ...
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qgif.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qgif.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QImageIOHandlerFactoryInterface",
    "MetaData": {
    "Keys": [
    "gif"
    ],
    "MimeTypes": [
    "image/gif"
    ]
    },
    "archreq": 0,
    "className": "QGifPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("gif")
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qico.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qico.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QImageIOHandlerFactoryInterface",
    "MetaData": {
    "Keys": [
    "ico",
    "cur"
    ],
    "MimeTypes": [
    "image/vnd.microsoft.icon",
    "image/vnd.microsoft.icon"
    ]
    },
    "archreq": 0,
    "className": "QICOPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("ico", "cur")
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qjpeg.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qjpeg.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QImageIOHandlerFactoryInterface",
    "MetaData": {
    "Keys": [
    "jpg",
    "jpeg"
    ],
    "MimeTypes": [
    "image/jpeg",
    "image/jpeg"
    ]
    },
    "archreq": 0,
    "className": "QJpegPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("jpg", "jpeg")
    QFactoryLoader::QFactoryLoader() looking at "C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qsvg.dll"
    Found metadata in lib C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qsvg.dll, metadata=
    {
    "IID": "org.qt-project.Qt.QImageIOHandlerFactoryInterface",
    "MetaData": {
    "Keys": [
    "svg",
    "svgz"
    ],
    "MimeTypes": [
    "image/svg+xml",
    "image/svg+xml-compressed"
    ]
    },
    "archreq": 0,
    "className": "QSvgPlugin",
    "debug": false,
    "version": 393472
    }

    Got keys from plugin meta data QList("svg", "svgz")
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Users/USER/Downloads/build-monitoreo_xertek-Desktop_Qt_6_1_2_MinGW_64_bit-Release/release/imageformats" ...
    loaded library "C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qgif.dll"
    loaded library "C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qico.dll"
    loaded library "C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qjpeg.dll"
    loaded library "C:/Qt/6.1.2/mingw81_64/plugins/imageformats/qsvg.dll"
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Qt/6.1.2/mingw81_64/plugins/accessible" ...
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Users/USER/Downloads/build-monitoreo_xertek-Desktop_Qt_6_1_2_MinGW_64_bit-Release/release/accessible" ...
    QSqlDatabasePrivate::addDatabase: duplicate connection name 'qt_sql_default_connection', old connection removed.
    La carpeta ya existe
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Qt/6.1.2/mingw81_64/plugins/accessiblebridge" ...
    QFactoryLoader::QFactoryLoader() checking directory path "C:/Users/USER/Downloads/build-monitoreo_xertek-Desktop_Qt_6_1_2_MinGW_64_bit-Release/release/accessiblebridge" ...


  • Lifetime Qt Champion

    @lincoln said in Why shows error message when generating application release:

    QSqlDatabasePrivate::addDatabase: duplicate connection name 'qt_sql_default_connection', old connection removed.

    You are still creating multiple QSqlDatabase objects using the default connection. One might be wrong.



  • @SGaist I changed the code in this way, but now it does not connect to the database, I think it is worse.

    DbConection class

    #ifndef DBCONECTION_H
    #define DBCONECTION_H
    #include <QSqlDatabase>
    #include <QSqlError>
    
    class DbConection
    {
    public:
      DbConection();
      bool connect(const QString &dbName);
      QString errorMessage(){return _errorMessage;}
      QSqlDatabase getDataBase();
    //  void removeDb();
    
    
    private:
      QString _errorMessage;
      QString mdbName;
    
    };
    
    #endif // DBCONECTION_H
    
    #include "dbconection.h"
    
    
    DbConection::DbConection(){
    
    }
    
    bool DbConection::connect(const QString &dbName)
    {
      mdbName=dbName;
      auto db=QSqlDatabase::addDatabase("QPSQL",dbName);
      if(!db.isDriverAvailable("QPSQL")){
          _errorMessage=db.lastError().driverText();
          return false;
        }
      db.setDatabaseName("monitoreo_db");
      db.setPort(5432);
      db.setHostName("127.0.0.1");
      db.setUserName("postgres");
      db.setPassword("2311046");
    
      if(!db.open()){
          _errorMessage=db.lastError().databaseText();
          return false;
        }
    
      return true;
    
    }
    
    QSqlDatabase DbConection::getDataBase()
    {
    
      return QSqlDatabase::database(mdbName);
    
    }
    

    BussinesLayer class:

    #ifndef BUSSINESLAYER_H
    #define BUSSINESLAYER_H
    
    #include <QSqlQuery>
    #include <QSqlError>
    #include "dbconection.h"
    
    class BussinesLayer : public QObject
    {
    
    public:
      BussinesLayer();  
      QVariantList selectData(QVariant id);
      
    private:
      QString _errorMessage;
      QString _errorCode;  
      DbConection db;
      
    };
    
    #endif // BUSSINESLAYER_H
    
    
    #include "bussineslayer.h"
    
    BussinesLayer::BussinesLayer()
    {
    
      db.connect("monitoreo");
    
    }
    
    QVariantList BussinesLayer::selectData(QVariant id)
    {
      QVariantList dataList;
      QSqlQuery qry(db.getDataBase());
      qry.prepare("SELECT * FROM grupo_minero WHERE id=?");
      qry.addBindValue(id);
      if(!qry.exec()){
        _errorMessage=qry.lastError().text();
        return dataList;
    }        
      return dataList;
    
    }
    

    now this message comes out
    90eb8376-77a3-4919-b820-17dab02b9cab-image.png
    šŸ˜ŸšŸ˜ 


  • Lifetime Qt Champion

    @lincoln said in Why shows error message when generating application release:

    DbConection::connect(const QString &dbName)

    ^Where do you call it now in your code? You need to call it once before using the database connection.



  • @jsulm
    He calls it in the BussinesLayer::BussinesLayer() constructor: db.connect("monitoreo");.

    @lincoln
    In DbConection::connect() you check for db.isDriverAvailable("QPSQL") after you have called QSqlDatabase::addDatabase(). I suggest you want to call it before.

    On error you set _errorMessage and return false, yet you don't check for that nor show the error message.

    Your console output still shows "duplicate connection", which implies you are still calling DbConection::connect() more than once. Since you call it from BussinesLayer constructor, maybe your outside world code creates a BussinesLayer more than once.

    Can you please put in your own qDebug() messages to see what is getting executed in your own code, and for your error messages. This is a standard part of programming. For example, put one in at the start of DbConection::connect(). If that gets printed out more than once, you are in trouble....



  • @JonB a business layer, I call it from several forms, in the private part of the .h file of each form, I declare a variable of type bussineslayer class, in that class I have all the code I need to be able to do the DB tasks.

    here for example in "mainwindow.h"

    a8cf38a1-159e-434c-8b08-280082413839-image.png

    and so on all the forms you need from the bussineslayer class.

    Use a QMessageBox, to display the message and this is what it displays
    d9357a81-1d27-4e34-9206-e580ae62cbee-image.png

    I don't understand, when I don't pass the name of the connection in QSqlDatabase :: addDatabase ("QPSQL", dbName);
    data is displayed normally.



  • @lincoln
    Please copy & paste code rather than a screenshot. Same for error messages. It makes life easier for everyone.

    You have written code to create a new database connection, unconditionally, in BussinesLayer's constructor. If you have multiple BussinesLayer instances you will be creating multiple, duplicate connections. As per the error message you showed you get.

    You don't want that, do you? Multiple connections to the database? So you had better change code not to do that. Why do you have multiple BussinesLayer' instances anyway?



  • @JonB

    Ok, I saw what my error is, I was not passing the name of the connection when creating my QsqlQuery.
    now if it shows the data without problems. so I remain.

    class for connection to DB:

    #ifndef DBCONECTION_H
    #define DBCONECTION_H
    #include <QSqlDatabase>
    #include <QSqlError>
    #include <QObject>
    
    
    class DbConection: public QObject
    {
    public:
      explicit DbConection(QObject *parent=nullptr);
      bool connect(const QString &dbName);
      QString errorMessage(){return _errorMessage;}
      QSqlDatabase getDataBase();
    //  void removeDb();
    
    private:
      QString _errorMessage;
      QString mdbName;
    
    };
    
    #endif // DBCONECTION_H
    
    
    #include "dbconection.h"
    #include <QDebug>
    
    DbConection::DbConection(QObject *parent):
      QObject(parent)
    {
    
    }
    
    bool DbConection::connect(const QString &dbName)
    {
      mdbName=dbName;
      //  auto db=QSqlDatabase::addDatabase("QPSQL",dbName);
      QSqlDatabase db;
      if(!db.isDriverAvailable("QPSQL")){
          _errorMessage=db.lastError().driverText();
    //      qDebug()<<_errorMessage;
          return false;
        }
      db=QSqlDatabase::addDatabase("QPSQL",dbName);
      db.setPort(5432);
      db.setHostName("127.0.0.1");
      db.setDatabaseName("monitoreo_db");
      db.setUserName("postgres");
      db.setPassword("2311046");
    
      if(!db.open()){
          _errorMessage=db.lastError().databaseText();
    //      qDebug()<<_errorMessage;
          return false;
        }
    
      return true;
    
    }
    
    QSqlDatabase DbConection::getDataBase()
    {
    
      return QSqlDatabase::database(mdbName);
    
    }
    
    

    BussinesLayer class:

    #ifndef BUSSINESLAYER_H
    #define BUSSINESLAYER_H
    
    #include <QSqlQuery>
    #include <QSqlError>
    #include "dbconection.h"
    
    class BussinesLayer : public QObject
    {
    
    public:
      explicit BussinesLayer(QObject *parent=nullptr);
      QHash<int, QString> selectDataClient();
      
    private:
      QString _errorMessage;
      QString _errorCode;  
      DbConection db;
      
    };
    
    #endif // BUSSINESLAYER_H
    
    
    #include "bussineslayer.h"
    #include <QDebug>
    BussinesLayer::BussinesLayer(QObject *parent):
      QObject(parent)
    {
    
      if(!db.connect("monitoreo"))
        qDebug()<<db.errorMessage();
    
    }
    
    QHash<int, QString> BussinesLayer::selectDataClient()
    {
      QHash<int,QString> dataList;
    
      QSqlQuery qry(db.getDataBase());
      qry.prepare("SELECT id,nombre_unidad FROM cliente");
    
      if(!qry.exec()){
          _errorMessage=qry.lastError().text();
           return dataList;
        }
      while(qry.next()){
          dataList.insert(qry.value(0).toInt(),qry.value(1).toString());
        }
      return dataList;
    }
    

    And this in the mainwindow:

    private:
      Ui::MainWindow *ui;
      BussinesLayer bLayer;
    
    void MainWindow::loadData()
    {
      QHash<int,QString> dataList;
      dataList=bLayer.selectDataClient();
      if(dataList.isEmpty()){
          QMessageBox::critical(this,qApp->applicationName(),bLayer.errorMessage());
          return;
        }
      ui->cboGrupo->addItems(dataList.values());  
    
    }
    

    But still the duplicate connection message persists, as I mentioned above, I have to create a new variable of type BussinesLayer in the other forms, in order to have access to the other data that I use in the other forms.


  • Lifetime Qt Champion

    Because if you have several BusinessLayer objects, they will all use the same named connection the way you implemented it.



  • @SGaist said in Why shows error message when generating application release:

    Because if you have several BusinessLayer objects, they will all use the same named connection the way you implemented it.

    Well, I was also able to solve the issue of generating the release, now the data is displayed correctly, what remains in doubt is, how do I access the functionality of my BussinesLayer class in the other forms, without that annoying message of duplicate connection.

    šŸ˜’ šŸ„“


  • Lifetime Qt Champion

    Currently you are using the same connection everywhere thus as we already suggested several times: do the initialisation once and be done with it.

    The other solution is to create a different named connection for each instance of BusinessLayer.



  • @SGaist said in Why shows error message when generating application release:

    Currently you are using the same connection everywhere thus as we already suggested several times: do the initialisation once and be done with it.
    The other solution is to create a different named connection for each instance of BusinessLayer.

    ok thanks


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