Again QTableWidget and QComboBox delegate

**Aki-Matti** · 4th March 2008, 12:53

I've gone through the older threads about this subject but didn't find anything regarding my problem at hand:

So I'm creating a QTableWidget which has some of its columns using a custom delegate which returns a QComboBox editor. My problem is that I cannot get it to work in all situations.

For example, I have my own ExcelDlg Dialog and in its constructor I create a QTableWidget and set it to using my delegate.

Like this:

Qt Code:

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QStringList values;
    values
       << "DESC"
       << "POS"
       << "ABNORMAL INTERRUPTION"
       << "TESTI VAAN"
       << "VIELÃ„ YKS";
 
   cDropdownTableWidgetItemDelegate delegate;
   delegate.setValues(values);
 
   QTableWidget *table = new QTableWidget(2,3,this);
   table->setItemDelegate(&delegate);
 
   lo = new QHBoxLayout();   
   lo->addWidget(table);

QStringList values;
    values
       << "DESC"
       << "POS"
       << "ABNORMAL INTERRUPTION"
       << "TESTI VAAN"
       << "VIELÃ„ YKS";

   cDropdownTableWidgetItemDelegate delegate;
   delegate.setValues(values);

   QTableWidget *table = new QTableWidget(2,3,this);
   table->setItemDelegate(&delegate);

   lo = new QHBoxLayout();   
   lo->addWidget(table);

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Unfortunately the result is an empty table, no cells of any kind, only horizontal and vertical header items are displayed correctly.

But when I use it in a newly created dialog, for example:

Qt Code:

Switch view

QStringList values;
   values
       << "DESC"
       << "POS"
       << "ABNORMAL INTERRUPTION"
       << "TESTI VAAN"
       << "VIELÃ„ YKS";
 
   cDropdownTableWidgetItemDelegate delegate;
   delegate.setValues(values);
 
   QDialog *dlg = new QDialog();
 
   QTableWidget *table = new QTableWidget(2,3,dlg);   
   table->setItemDelegate(&delegate);
 
   dlg->exec();

QStringList values;
   values
       << "DESC"
       << "POS"
       << "ABNORMAL INTERRUPTION"
       << "TESTI VAAN"
       << "VIELÃ„ YKS";

   cDropdownTableWidgetItemDelegate delegate;
   delegate.setValues(values);
    
   QDialog *dlg = new QDialog();

   QTableWidget *table = new QTableWidget(2,3,dlg);   
   table->setItemDelegate(&delegate);

   dlg->exec();

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It works fine. What is happening? Why is it not working in the upper example?

If needed, i can post the code to my delegate.

**jpn** · 4th March 2008, 13:04

In the first case the item delegate goes out of scope (you might want to allocate it on the heap instead). In the second case QDialog::exec() blocks so the stack object remains valid until the dialog is accepted or rejected.