How do I check the state of a QListWidget's item's radiobuttons?

moyin

Hello,
I've been struggling with a problem about items of QListWidgets. i have a qlistwidget with radiobuttons as list elements. now i want to read the text of selected element(radiobutton). Please let me is there any way to get this to work.

Taz742

@moyin said in How do I check the state of a QListWidget's item's radiobuttons?:

i have a qlistwidget with radiobuttons

How ? Like setItemWidget ? If you are using RadioButton only 1 will be selected.

Maybe you are using checkbox ?

If yes:

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include "QDebug"
#include "QFileDialog"
#include "QFile"
#include "QRadioButton"
#include "QCheckBox"

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    for (int i = 0; i < 10; i++) {
        auto item = new QListWidgetItem(ui->listWidget);
        ui->listWidget->setItemWidget(item, new QCheckBox(QString("Item %1").arg(i)));
    }
}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::on_pushButton_clicked()
{
    for (int i = 0; i < ui->listWidget->count(); i++) {
        auto checkBox = static_cast<QCheckBox*>(ui->listWidget->itemWidget(ui->listWidget->item(i)));
        if (checkBox->isChecked()) {
            qDebug() << checkBox->text();
        }
    }
}

moyin

@Taz742
thanks for rply,
No i'm using radio buttons only, but i want the text of the selected one, so i can pass to the other functions.

JonB

@moyin
If you have a "list widget with radio button items", that implies single selection from a list. Does you usage allow instead for a QCombobox, which is simplest?

Taz742

@moyin
I edited my answer.
Then you can edit

auto checkBox = static_cast<QCheckBox*>(ui->listWidget->itemWidget(ui->listWidget->item(i)));

to

auto radioButon = static_cast<QRadioButton*>(ui->listWidget->itemWidget(ui->listWidget->item(i)));

moyin

@JonB
thnks for rply,
yes i know it will be simple if i go with checkbox, but my requirment is to select one at a time and multiple selections should not allow.

JonB

@moyin
Then if you had not used the "radio buttons" you could have gone for http://doc.qt.io/qt-5/qabstractitemview.html#selectionMode-prop with single-selection. Using radio buttons in each item I assume you'll have to manage the selection/deselection yourself.

VRonin

why are you using setItemWidget?
Can you use Qt 5.11? (the solution is a lot easier if you reply yes)

moyin

@VRonin
yes, sure i can use Qt5.11

mad-hatter

Hello,

What you want could be done with signals & slots, something like this .
This is using a grid layout but you could use any container.

Regards

QString num;
    QGridLayout *layout = new QGridLayout;
    for( int i = 0; i < 10; i++ )
    {
        QRadioButton *RB = new QRadioButton;
        RB->setFixedHeight(14);
        num = QString::number(i);
        RB->setObjectName( num );
        RB->setText( num + " - " );

	if ( i == 0 )
		{
			RB->setChecked( true );
			RB->setText( RB->text() + " (got)" );
        }
		
        QObject::connect( RB, SIGNAL( toggled( bool ) ), this,
                          SLOT( onWhichButtonSlot( bool ) ) );
        layout->addWidget( RB );
    }

void yourClass::onWhichButtonSlot( bool state )
{
      QObject *object = QObject::sender();
      QRadioButton *btn = qobject_cast<QRadioButton *>(object);

    if (state)
    {
        btn->setText( btn->text() + " (got)" );
    }
    else
    {
        btn->setText( btn->text().remove( " (got)" ) );
    }
}

VRonin

Example, only works in Qt 5.11 or later:

#include <QApplication>
#include <QListWidget>

int main(int argc, char *argv[])
{
    QApplication application(argc, argv);
    QListWidget mainWid;
    mainWid.model()->insertRows(0,10);
    for(int i=0;i<mainWid.model()->rowCount();++i){
       QListWidgetItem* item = mainWid.item(i);
       item->setFlags(item->flags() | Qt::ItemIsUserCheckable );
       item->setData(Qt::CheckStateRole,Qt::Unchecked);
       item->setData(Qt::EditRole, "Item " + QString::number(i));
    }
    QObject::connect(mainWid.model(),&QAbstractItemModel::dataChanged,[&mainWid](const QModelIndex& topLeft,const QModelIndex& bottomRight,const QVector<int>& roles)->void{
        Q_ASSERT(topLeft==bottomRight);
        if(!roles.contains(Qt::CheckStateRole))
            return;
        if(topLeft.data(Qt::CheckStateRole)!=Qt::Checked)
            return;
        for(int i=0;i<mainWid.model()->rowCount();++i){
            if(i==topLeft.row())
                continue;
            mainWid.item(i)->setData(Qt::CheckStateRole,Qt::Unchecked);
        }
    });
    mainWid.show();
    return application.exec();
}