Can't find linker symbol for virtual table
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There is no variable printPreview in your code, if you modify it, please leave a note, so that readers can follow the discussion.
Can you show us the code for your slot in Dialog2, please. Also, a stack trace of the crash would be helpful.
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I assume that the variable is initialized properly as the dialog2 does open when the emit signal is commented out. The dialog opens without a problem but obviously the data is not sent.
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We know nothing about what is sent or not, as we do not have a stack trace.
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You have completely changed the code. You are now connecting the signal up to a slot on dialog2 now instead of printPreview.
Can you please either:
Provide a complete backtrace as Volker asked or
upload a tarball of a small compileable example that reproduces the problem
You will most likely spot the problem yourself in preparing the example.
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How do I get a stack trace? I am not at a computer with a complier. I will provide the info when I find out how and get back to my computer.
Here is the code for the slot:
dialog2.h
@private slots:
void createReportTable(QStringList);
@
dialog2.cpp
@void Dialog2::createReportTable(QStringList stringList)
{
QStringList reportOptions=stringList;
printModel= new QSqlRelationalTableModel (this);
printModel-> setEditStrategy(QSqlTableModel::OnRowChange);
printModel-> setTable (mTableName);
printModel-> setRelation (2, QSqlRelation("rider", "id", "LName"));
printModel-> setRelation (3, QSqlRelation("track", "id", "TrackName"));
printModel-> setRelation (4, QSqlRelation("bike", "id", "BikeName"));//set up printview ui->printView->setModel(printModel); ui->printView->setItemDelegate(new QSqlRelationalDelegate(this)); ui->printView->setSelectionMode(QAbstractItemView::SingleSelection); ui->printView->setSelectionBehavior(QAbstractItemView::SelectRows); ui->printView->setColumnHidden(0,true); ui->printView->setColumnHidden(1, true); ui->printView->setColumnHidden(2, true); ui->printView->setColumnHidden(3, true); ui->printView->setColumnHidden(4, true);
if (reportOptions.at(0)=="FSChecked") {
printModel->setHeaderData (5, Qt::Horizontal, "Front \n Spring");
printModel->setHeaderData (6, Qt::Horizontal, "Spring \n Preload");
printModel->setHeaderData (7, Qt::Horizontal, "Oil \n Weight");
printModel->setHeaderData (8, Qt::Horizontal, "Oil \n Height");
printModel->setHeaderData (9, Qt::Horizontal, "Front \n Compression");
printModel->setHeaderData (10, Qt::Horizontal, "Front \n Rebound");
printModel->setHeaderData (11, Qt::Horizontal, "Fork \n Tube Height");
}else //hide column and place in labels { ui->printView->setColumnHidden(5,true); //Front Spring Rate ui->printView->setColumnHidden(6,true); //Front Spring Preload ui->printView->setColumnHidden(7,true); //Front Oil Weight ui->printView->setColumnHidden(8,true); //Oil Height ui->printView->setColumnHidden(9,true); //Front Compression ui->printView->setColumnHidden(10,true); //Front rebound ui->printView->setColumnHidden(11, true); //Fork Tube Height //Need to place data in lables }
if (reportOptions.at(1)== "FTireChecked") //Front tire changes
{
printModel->setHeaderData (12, Qt::Horizontal, "Tire Type");
printModel->setHeaderData (13, Qt::Horizontal, "Tire \n Pressure");
printModel->setHeaderData (14, Qt::Horizontal, "Tire \n Modifications");
}
else
{
//itemColumn +=;
ui->printView->setColumnHidden(12,true);//Tire Type
ui->printView->setColumnHidden(13,true);//Tire Pressure
ui->printView->setColumnHidden(14,true);//Tire Modifications
}printModel->setFilter(mFilterString); //mFilterString is initialized earlier
printModel->select();//Set lables and static data
}@
I will get a small compileable example when I get to my computer. -
If you run your program in an development environment (Qt Creator, Visual Studio or the like), you will get it almost automatically, once the program crashes.
As you do not give us information about your environment, we cannot help you further on this.
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I am using QT Creator. I am not getting anything backtrace info. I posted the error messages but I am sure there is more than that in a backtrace. After digging deeper and stepping through the program a million times, I think the problem actually lies in dialog2 when it is creating the table. in particular this line:
@printModel->setFilter(mFilterString); //mFilterString is initialized earlier @
I am stepping through it...I think I might get it...if not I will keep you posted
But if you could give me the info on getting the backtrace, it would be greatly appreciated. Another tool to help me resolve problems.Thanks
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That was the problem! In the string manipulation, there were two single quotes when there should have been a single quote! I would still like the info on getting a backtrace.
Thanks again
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When you pause the app in the debugger (either manually or hitting a breakpoint or getting a crash) you should be able to see the call stack in one of the debug panels in qt-creator. From there you can copy it to the clipboard via the context menu.
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Hello, i have the same problem, it wrote me:
can't find linker symbol for virtual table forQStandardItem' value found
qEmptyModel()::cleanup' insteaddebugger stopped on:
@void MyClass::currentChanged ( const QModelIndex & indexCurrent, const QModelIndex & indexPrevious ){
QStandardItem *current = comparisonModel->item(indexCurrent.row(), 0);
}@i know, im accesing something what didnt exist, because of the message,
because I have model set on QTreeView, and indexes have children... but how to acces that item, when i have only index?