select all content upon receiving focus

lincoln

hello guys, I have the following problem, I have a QTableWidget to which I have added some QDoubleSpinBox to some cells, all good so far my question is how can I do to select all the content of the spinbox when changing the focus, I mean when pressing the tab key and when they receive the focus, and also when it is clicked inside the control. I would appreciate any suggestions.

I leave my code:

void MainClass::setData(double val1, double val2,int _rowCount)
{

  for (int i=0;i<= _rowCount; i++) {
      int rowCount=ui->tableWidget_4->rowCount();
      //  ui->tableWidget_4->setRowCount(rowCount);
      //primera columna
      ui->tableWidget_4->insertRow(rowCount);
      //  qDebug()<<rowCount;
      QTableWidgetItem *item=new QTableWidgetItem(QString("v %1").arg(v));
      ui->tableWidget_4->setItem(rowCount,V,item);

      //segunda columna columna
      //  ui->tableWidget_4->insertRow(rowCount);


      QTableWidgetItem *item1=new QTableWidgetItem(0);
      ui->tableWidget_4->setItem(rowCount,Velocidad,item1);
      ui->tableWidget_4->setCellWidget(rowCount,Velocidad,new QDoubleSpinBox);
      QDoubleSpinBox *sb=qobject_cast<QDoubleSpinBox *>(
            ui->tableWidget_4->cellWidget(rowCount,Velocidad));
      sb->setValue(val1);
      //  qDebug()<<item1->data(Qt::DisplayRole).toString();
      //tercera columna columna
      //  ui->tableWidget_4->insertRow(rowCount);
      QTableWidgetItem *item2=new QTableWidgetItem(QString("h %1").arg(h));
      ui->tableWidget_4->setItem(rowCount,H,item2);
      //cuarta columna columna
      //  ui->tableWidget_4->insertRow(rowCount);
      QTableWidgetItem *item3=new QTableWidgetItem(val2);
      ui->tableWidget_4->setItem(rowCount,Profundidad,item3);
      ui->tableWidget_4->setCellWidget(rowCount,Profundidad,new QDoubleSpinBox);
      QDoubleSpinBox *sb2=qobject_cast<QDoubleSpinBox *>(
            ui->tableWidget_4->cellWidget(rowCount,Profundidad));
      sb2->setValue(val2);
      v++;
      h++;
    }

here the form

Note that when the spinboxes are in focus, only the cursor blinks but not all the content is selected.

note:
in the assignment of the column number in setItem I use an enumeration instead of the column numbers.

enum ColNames{V,Velocidad,H,Profundidad};