Getting multiple inputs from QInputDialog in Qt - c++

Question

I would like to get a set of four values from four input labels in Qt. I would like to use QInputDialog but it contains only one inputbox as a default one. So, how can I add four labels and four line-edits and get the value from it?

Answer 1

You don't. The documentation is pretty clear:
The QInputDialog class provides a simple convenience dialog to get a
single value from the user.
If you want multiple values, create a QDialog derived class from scratch with 4 input fields.
For example:
QDialog dialog(this);
// Use a layout allowing to have a label next to each field
QFormLayout form(&dialog);
// Add some text above the fields
form.addRow(new QLabel("The question ?"));
// Add the lineEdits with their respective labels
QList<QLineEdit *> fields;
for(int i = 0; i < 4; ++i) {
QLineEdit *lineEdit = new QLineEdit(&dialog);
QString label = QString("Value %1").arg(i + 1);
form.addRow(label, lineEdit);
fields << lineEdit;
}
// Add some standard buttons (Cancel/Ok) at the bottom of the dialog
QDialogButtonBox buttonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel,
Qt::Horizontal, &dialog);
form.addRow(&buttonBox);
QObject::connect(&buttonBox, SIGNAL(accepted()), &dialog, SLOT(accept()));
QObject::connect(&buttonBox, SIGNAL(rejected()), &dialog, SLOT(reject()));
// Show the dialog as modal
if (dialog.exec() == QDialog::Accepted) {
// If the user didn't dismiss the dialog, do something with the fields
foreach(QLineEdit * lineEdit, fields) {
qDebug() << lineEdit->text();
}
}

Answer 2

Following alexisdm's answer, here is one way to implement custom QInputDialog.
"inputdialog.h":
#ifndef INPUTDIALOG_H
#define INPUTDIALOG_H
#include <QDialog>
class QLineEdit;
class QLabel;
class InputDialog : public QDialog
{
Q_OBJECT
public:
explicit InputDialog(QWidget *parent = nullptr);
static QStringList getStrings(QWidget *parent, bool *ok = nullptr);
private:
QList<QLineEdit*> fields;
};
#endif // INPUTDIALOG_H
"inputdialog.cpp":
#include "inputdialog.h"
#include <QLabel>
#include <QLineEdit>
#include <QDialogButtonBox>
#include <QFormLayout>
InputDialog::InputDialog(QWidget *parent) : QDialog(parent)
{
QFormLayout *lytMain = new QFormLayout(this);
for (int i = 0; i < 4; ++i)
{
QLabel *tLabel = new QLabel(QString("Text_%1:").arg(i), this);
QLineEdit *tLine = new QLineEdit(this);
lytMain->addRow(tLabel, tLine);
fields << tLine;
}
QDialogButtonBox *buttonBox = new QDialogButtonBox
( QDialogButtonBox::Ok | QDialogButtonBox::Cancel,
Qt::Horizontal, this );
lytMain->addWidget(buttonBox);
bool conn = connect(buttonBox, &QDialogButtonBox::accepted,
this, &InputDialog::accept);
Q_ASSERT(conn);
conn = connect(buttonBox, &QDialogButtonBox::rejected,
this, &InputDialog::reject);
Q_ASSERT(conn);
setLayout(lytMain);
}
QStringList InputDialog::getStrings(QWidget *parent, bool *ok)
{
InputDialog *dialog = new InputDialog(parent);
QStringList list;
const int ret = dialog->exec();
if (ok)
*ok = !!ret;
if (ret) {
foreach (auto field, dialog->fields) {
list << field->text();
}
}
dialog->deleteLater();
return list;
}
Now you can use getStrings() method similar to QInputDialog::getText():
QStringList list = InputDialog::getStrings(this);
if (!list.isEmpty()) {
// use list
}
Or
bool ok;
QStringList list = InputDialog::getStrings(this, &ok);
if (ok) {
// use list
}