QByteArray function
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Hello, I am trying to pass QByteArray data from one class to another class in a different file. I am able to send and receive the data because when I print with qDebug it shows. But I'm not able to use it out of the function, I have tried to append, but when I print or try to use "useData" it shows nothing, it only shows if I print inside transportPic(). How can I get the data out of the function? Thanks
code:public: QByteArray transportPic(QByteArray name){ useData = name; qDebug() << "ByteArray " << name.toHex(); return name; } private: QByteArray useData; -
@Ucn_
Is yourtransportPicpublic? -
@russjohn834 yes it's public.
@fcarney I try to insert into my database, I have tested using the code bellow, It worked then I moved to another class because of some conditions. I pass the parameters the QByteArray comes till the "transport()" and it prints the data, but it doesn't show in the desired function.//I moved this code to another class and pass the parameter through "transport()" in the "transport()" I can print and the data is there. // QPixmap inPixmap; // inPixmap.load(":/file/mypic"); // QByteArray inByteArray; // QBuffer inBuffer( &inByteArray ); // inBuffer.open( QIODevice::WriteOnly ); // inPixmap.save( &inBuffer, "JPG" ); QSqlQuery query; query.setForwardOnly(true); query.prepare("{CALL InsertTestingImg(? , ?, ?, ?)}"); query.bindValue(0, createdB); query.bindValue(1, imgtext); query.bindValue(2, imgtexts); query.bindValue(3, useData); //I use it here //And test here qDebug() << "Send Array from DbPic" << useData.toHex(); ...... -
@Ucn_ said in QByteArray function:
Could you help with this?
Please show us code where you call your class function and where you execute your function with the sql stuff.
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sqlServerconnection.h
public: ...... QByteArray transportPic(QByteArray name){ useData = name; qDebug() << "ByteArray " << name.toHex(); return name; } void setStudentData(QString fname, QString sname,QString lname, QString gender, QString birthday, QString country, QString city, QString telephonN, QString stdId, QString eduLevel, QString status, QString bookLevel, QString classR, QString classT){ insertStudentData(fname, sname, lname, gender, birthday, country, city, telephonN, stdId, eduLevel, status, bookLevel, classR, classT); } private: QByteArray useData; .....sqlServerconnection.cpp
void sqlServerConnection::insertStudentData(QString fname, QString sname,QString lname, QString gender, QString birthday, QString country, QString city, QString telephonN, QString stdId, QString eduLevel, QString status, QString bookLevel, QString classR, QString classT) { // QPixmap inPixmap; // inPixmap.load(":/file/mypics"); // QByteArray inByteArray; // QBuffer inBuffer( &inByteArray ); // inBuffer.open( QIODevice::WriteOnly ); // inPixmap.save( &inBuffer, "JPG" ); QString name = "nameTest"; QString lname = "lnameTest"; QString imgname = "pic.jpg"; QDateTime currentDT = QDateTime::currentDateTime(); QSqlQuery query; query.setForwardOnly(true); query.prepare("{CALL InsertTestingImg(? , ?, ?, ?)}"); query.bindValue(0, name); query.bindValue(1, lname); query.bindValue(2, imgname); query.bindValue(3, useData); if( !query.exec() ){ qDebug() << "Error inserting into table:\n" << query.lastError(); } qDebug() << "useData Test" << useData.toHex(); }Secondui.cpp
SecondUi::loadAndSetPic(QStringList fileNames, QByteArray outByteArray, qint32 funcSender) { switch (funcSender) { case 1: { QPixmap inPixmap; inPixmap.load(":/file/mypics"); QByteArray inByteArray; QBuffer inBuffer( &inByteArray ); inBuffer.open( QIODevice::WriteOnly ); inPixmap.save( &inBuffer, "JPG" ); QPixmap outPixmap = QPixmap(); outPixmap.loadFromData( inByteArray ); sqlServerConnection *sendPicArray; sendPicArray = new sqlServerConnection(); sendPicArray->transportPic(inByteArray); studentViewPic->setPixmap(outPixmap.scaled(100,100,Qt::KeepAspectRatio)); } break; case 2: break; } } void SecondUi::on_pushButton_3_clicked() { sqlServerConnection *setStudentInfo; setStudentInfo = new sqlServerConnection(); setStudentInfo->setStudentData(ui2.nameLineEdit->text(), ui2.middleNameLineEdit->text(), ui2.surnameLineEdit->text(), ui2.genderComboBox->currentText(), ui2.birthDateDateEdit->text(), ui2.countryLineEdit->text(), ui2.cityLineEdit->text(), ui2.telephoneLineEdit->text(), ui2.studentIdLineEdit->text(), ui2.educationLevelComboBox->currentText(), ui2.statusComboBox->currentText(), ui2.bookLevelComboBox->currentText(), ui2.classroomComboBox->currentText(), ui2.classTimeComboBox->currentText()); } -
@Ucn_ said in QByteArray function:
And where do you call insertStudentData? You're creating a new, local instance inside the switch statement but don't do anything with it apart from calling transportPic() function and leaking this object afterwards,
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@Christian-Ehrlicher I updated the code to show where I call insertStudentData, where do I create the instance? Actually apart from transportPic() I use it in other functions, but when I create where my class initialize and try to use in the functions it says is not declared. I delete the pointer after
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Now you're creating two instances of sqlServerConnection - one in on_pushButton_3_clicked() and one in loadAndSetPic(). If you want to have one instance you should e.g. make them a member pointer - C++ basics.
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@Christian-Ehrlicher I see, thanks. Is that the reason for the QByteArray not displaying when trying to use?
