SOLVED [Find an QstandardItemModel in tabWidget !

[cout Eureka]

hi everybody !

i've an problem to find my QStandardItemModel in tabWidget.

I use Tableview to see QstandardItemModel, i have created 2 tableView by using a QtabWidget.

I would like read th item in each tableView, but i can't. It's only possible in the last created. i am using QObject::findchild(), but it doesn't operate.(it's ok if i repalce my QtableView & QStandardItemModel by Qlabel !)

se may code below, thanks for your help.
(be aware with my english ;-) )

i dont have include the main here, but it is classical.

my .cpp

@#include "main_window.h"

main_window::main_window(QWidget *parent) : QMainWindow(parent)
{

//Main Window
QMdiArea *mdi = new QMdiArea;
setCentralWidget(mdi);
this->setWindowTitle("Main Window");
this->resize(550,400);

//command panel
QGroupBox *cmd = new QGroupBox("Add Tab");
cmd->setTitle("Command Panel");
cmd->setFixedWidth(250);

//init command panel
lbl_cmd = new QLabel("Nom de tabulation");
lbl_cmd->setAlignment(Qt::AlignHCenter);
str_lbl = "empty";
lbl_tab0 = new QLabel;
lbl_tab1 = new QLabel;
lblTab();

//button command panel
QPushButton *exit = new QPushButton("Exit");
QPushButton *table_buton = new QPushButton("TableView");
QPushButton *lbl_buton = new QPushButton("lblTab display");
QPushButton *stdItmModel_buton = new QPushButton("stdItmModel");
QPushButton *ouv_fichier_buton = new QPushButton("Not Use");

//TableView display
tabu = new QTabWidget;

//layout command panel
QHBoxLayout *h_bouton1 = new QHBoxLayout;
h_bouton1->addWidget(table_buton);h_bouton1->addWidget(lbl_buton);

QHBoxLayout *h_bouton2 = new QHBoxLayout;
h_bouton2->addWidget(stdItmModel_buton);h_bouton2->addWidget(ouv_fichier_buton);

QVBoxLayout *v_cmd = new QVBoxLayout;
v_cmd->addWidget(lbl_cmd);
v_cmd->addWidget(lbl_tab0);
v_cmd->addWidget(lbl_tab1);
v_cmd->addLayout(h_bouton1);
v_cmd->addLayout(h_bouton2);
v_cmd->addWidget(exit);
cmd->setLayout(v_cmd);

//Layout main window
QHBoxLayout *h_lay = new QHBoxLayout;
h_lay->addWidget(tabu);
h_lay->addWidget(cmd);
mdi->setLayout(h_lay);

//Connect
connect(table_buton,SIGNAL(clicked()),this,SLOT(tableView()));
connect(exit,SIGNAL(clicked()),this,SLOT(close()));
connect(lbl_buton,SIGNAL(clicked()),this,SLOT(str_lbl_chg()));
connect(stdItmModel_buton,SIGNAL(clicked()),this,SLOT(stdItmModel()));
}

void main_window::tableView()
{
for (int l(0);l<2;l++) //create 2 tableView
{
table = new QTableView;
QString str;
modele = new QStandardItemModel(5,2);
modele->setHeaderData(0,Qt::Horizontal,"Col 0");
modele->setHeaderData(1,Qt::Horizontal,"Col 1");
modele->setHeaderData(0,Qt::Vertical,"L 0");
modele->setHeaderData(1,Qt::Vertical,"L 1");
modele->setHeaderData(2,Qt::Vertical,"L 2");
modele->setHeaderData(3,Qt::Vertical,"L 3");
modele->setHeaderData(4,Qt::Vertical,"L 4");

    for (int loopA(0);loopA<5;loopA++) //filing tablView
    {
        QString strLoopA;
        stdIt = new QStandardItem;
        stdIt->setText("value tab"+str.setNum(l)+" "+strLoopA.setNum(loopA)+"x0");
        modele->setItem(loopA,0,stdIt);
        stdIt = new QStandardItem;
        stdIt->setText("value tab "+str.setNum(l)+" "+strLoopA.setNum(loopA)+"x1");
        modele->setItem(loopA,1,stdIt);
    }
    table->setModel(modele);
    tabu->addTab(table,"tab "+str.setNum(l)); //add TabWidget
}

}
void main_window::lblTab() //display in command panel
{
lbl_tab0->setText("tab0 value of row 1,col 0 : "+str_lbl);
lbl_tab1->setText("tab1 value of row 2,col 1 : "+str_lbl);
}
void main_window::str_lbl_chg() //mofidifcation command panel display
{
//str_lbl = "test ok"; // remove//before str_lbl to performed lbl modification test
str_lbl = stdItmModel()->item(1,0)->text();
str_lbl = stdItmModel()->item(2,1)->text();
lblTab();
}
QStandardItemModel *main_window::stdItmModel() // to return QStandardItemModel in active tabWidget
{
return tabu->currentWidget()->findChild <QStandardItemModel *>();
}
@

my .h
@#ifndef MAIN_WINDOW_H
#define MAIN_WINDOW_H

#include <QApplication>
#include <QDialog>
#include <QFile>
#include <QFormLayout>
#include <QGroupBox>
#include <QHBoxLayout>
#include <QInputDialog>
#include <QLabel>
#include <QMainWindow>
#include <QMdiArea>
#include <QMessageBox>
#include <QPushButton>
#include <QStandardItem>
#include <QStandardItemModel>
#include <QTableView>
#include <QTabWidget>
#include <QTextStream>
#include <QLineEdit>
#include <QVBoxLayout>

class main_window : public QMainWindow
{
Q_OBJECT
public:
main_window(QWidget *parent = 0);
QLabel *lbl_cmd, *lbl_tab0, *lbl_tab1;
QString *str, msgbox;
QStandardItem *stdIt;
QStandardItemModel *modele;
QString str_lbl;
QTableView *table;
QTabWidget *tabu;

signals:

public slots:
void tableView();
void lblTab();
void str_lbl_chg();

QStandardItemModel *stdItmModel();

};

#endif // MAIN_WINDOW_H
@

[lgeyer]

The QTableView does not take ownership of the model set with QTableView::setModel(); you will have to parent it explicitly (<code>modele = new QStandardItemModel(5,2,table)</code>) so it becomes a child of the QTableView.

The model can be retrieved later on using QTableView::model().
@
QStandardItemModel main_window::stdItmModel()
{
return static_cast<QStandardItemModel>(static_cast<QTableView*>(tabu->currentWidget())->model());
}
@

[cout Eureka]

Hi Lukas,
thanks for your help, now is operate ! :-)

Can you explane what is static_cast?

because is operate with this code
@QStandardItemModel *main_window::stdItmModel() // to return QStandardItemModel in active tabWidget
{
return tabu->currentWidget()->findChild <QStandardItemModel *>();
}
@
with add my tableView like parents to my modele.

thanks !

[lgeyer]

A "static_cast":http://en.wikipedia.org/wiki/Static_cast is used to "downcast":http://en.wikipedia.org/wiki/Downcasting from the base class pointer of QWidget* returned by QTabWidget::currentWidget() to the derived class pointer of type QTableView*, so we can access the QTableView::model() method.

When you've added your widget using QTabWidget::addTab() you were supplying a pointer of type QTableView* (which was implicitly upcasted to a pointer of QWidget*, because QTabWidget::addTab() takes a pointer of QWidget* as parameter), but using QTabWidget::currentWidget() will get you only a pointer of type QWidget* out (the common base class of all widgets). To access the QTableView::model() method you will have to 'convert' your pointer of type QWidget* back to a pointer of type QTableView*. This is done using a static_cast.

[cout Eureka]

Nice !

thank you and have nice day !

[lgeyer]

You're weclome!