在Qt中如何在QLineEdit中添加一个QFileDialog文件

我有一个窗口，它有一个名为"…"的按钮，打开另一个窗口，它也有一个名为"…"的按钮，打开一个QFileDialog。在第二个窗口的按钮旁边，有10个QLineEdit来获取10个文件。与QFileDialog，我不能拿一个mp3文件，并把他的名字在第一个QLineEdit。我该怎么办?如果第一个QLineEdit已经被占用了，我怎么能把mp3文件的名字放在第二个QLineEdit中呢?

文件"main.h"只包含Qt.这是我的代码，我尝试了许多解决方案都没有成功:

#include "main.h"
int     main(int argc, char **argv)
{
QApplication    program(argc, argv);
/* ******************** First Window ******************** */
QWidget         window;
QVBoxLayout     layout;
window.setWindowTitle("Programme");
window.setWindowIcon(QIcon(":/Images/Images/Bouclier.png"));
window.setFixedSize(450, 400);
    QHBoxLayout     layouttop;
            QLabel          labeltop("Nom du programme :");
            QLineEdit       lineedittop;
                layouttop.addWidget(&labeltop);
                layouttop.addWidget(&lineedittop);
    QHBoxLayout     layoutmiddle;
            QPushButton     buttonnext;
            QPushButton     buttonprevious;
            QPushButton     buttonetc("...");
            QLineEdit       line0;
            QLineEdit       line1;
            QLineEdit       line2;
            QLineEdit       line3;
            QLineEdit       line4;
            QLineEdit       line5;
            QLineEdit       line6;
            QLineEdit       line7;
            QLineEdit       line8;
            QLineEdit       line9;
        QVBoxLayout     layoutleft;
                layoutleft.addWidget(&buttonnext);
                buttonnext.setIcon(QIcon(":/Images/Images/Haut.png"));
                layoutleft.addWidget(&buttonprevious);
                buttonprevious.setIcon(QIcon(":/Images/Images/Bas.png"));
        QVBoxLayout     layoutcenter;
                layoutcenter.addWidget(&line0);
                layoutcenter.addWidget(&line1);
                layoutcenter.addWidget(&line2);
                layoutcenter.addWidget(&line3);
                layoutcenter.addWidget(&line4);
                layoutcenter.addWidget(&line5);
                layoutcenter.addWidget(&line6);
                layoutcenter.addWidget(&line7);
                layoutcenter.addWidget(&line8);
                layoutcenter.addWidget(&line9);
                line0.setReadOnly(true);
                line1.setReadOnly(true);
                line2.setReadOnly(true);
                line3.setReadOnly(true);
                line4.setReadOnly(true);
                line5.setReadOnly(true);
                line6.setReadOnly(true);
                line7.setReadOnly(true);
                line8.setReadOnly(true);
                line9.setReadOnly(true);
        QVBoxLayout     layoutright;
                layoutright.addWidget(&buttonetc);
                layoutmiddle.addLayout(&layoutleft);
                layoutmiddle.addLayout(&layoutcenter);
                layoutmiddle.addLayout(&layoutright);
    QHBoxLayout     layoutbottom;
            QPushButton     buttonapply("Apply");
            QPushButton     buttoncancel("Cancel");
                layoutbottom.addWidget(&buttonapply);
                layoutbottom.addWidget(&buttoncancel);
layout.addLayout(&layouttop);
layout.addLayout(&layoutmiddle);
layout.addLayout(&layoutbottom);
window.setLayout(&layout);
window.show();
/* ******************** First Window ******************** */
/* ******************** Second Window ******************** */
QWidget         windowed;
QVBoxLayout     layouted;
windowed.setWindowTitle("Session");
windowed.setWindowIcon(QIcon(":/Images/Images/Bouclier.png"));
windowed.setFixedSize(450, 400);
    QHBoxLayout     layouttoped;
            QLabel          labeltoped("Nom de la session :");
            QLineEdit       lineedittoped;
                layouttoped.addWidget(&labeltoped);
                layouttoped.addWidget(&lineedittoped);
    QHBoxLayout     layoutmiddled;
            QPushButton     buttonnexted;
            QPushButton     buttonprevioused;
            QPushButton     buttonetced("...");
            QString         file;
            QLineEdit       lined0;
            QLineEdit       lined1;
            QLineEdit       lined2;
            QLineEdit       lined3;
            QLineEdit       lined4;
            QLineEdit       lined5;
            QLineEdit       lined6;
            QLineEdit       lined7;
            QLineEdit       lined8;
            QLineEdit       lined9;
            QComboBox       box;
            QLabel          label("Durée :");
        QVBoxLayout     layoutlefted;
                layoutlefted.addWidget(&buttonnexted);
                buttonnexted.setIcon(QIcon(":/Images/Images/Haut.png"));
                layoutlefted.addWidget(&buttonprevioused);
                buttonprevioused.setIcon(QIcon(":/Images/Images/Bas.png"));
        QVBoxLayout     layoutcentered;
                layoutcentered.addWidget(&lined0);
                layoutcentered.addWidget(&lined1);
                layoutcentered.addWidget(&lined2);
                layoutcentered.addWidget(&lined3);
                layoutcentered.addWidget(&lined4);
                layoutcentered.addWidget(&lined5);
                layoutcentered.addWidget(&lined6);
                layoutcentered.addWidget(&lined7);
                layoutcentered.addWidget(&lined8);
                layoutcentered.addWidget(&lined9);
                lined0.setReadOnly(true);
                lined1.setReadOnly(true);
                lined2.setReadOnly(true);
                lined3.setReadOnly(true);
                lined4.setReadOnly(true);
                lined5.setReadOnly(true);
                lined6.setReadOnly(true);
                lined7.setReadOnly(true);
                lined8.setReadOnly(true);
                lined9.setReadOnly(true);
        QVBoxLayout     layoutrighted;
                layoutrighted.addWidget(&buttonetced);
        QVBoxLayout     layoutmore;
            QHBoxLayout     layoutmored;
                layoutmored.addWidget(&label);
                layoutmored.addWidget(&box);
                box.addItem("30");
                box.addItem("60");
                layoutmore.addLayout(&layoutmored);
                layoutmiddled.addLayout(&layoutlefted);
                layoutmiddled.addLayout(&layoutcentered);
                layoutmiddled.addLayout(&layoutrighted);
                layoutmiddled.addLayout(&layoutmore);
    QHBoxLayout     layoutbottomed;
        QPushButton     buttonapplyed("Apply");
        QPushButton     buttoncanceled("Cancel");
                layoutbottomed.addWidget(&buttonapplyed);
                layoutbottomed.addWidget(&buttoncanceled);
layouted.addLayout(&layouttoped);
layouted.addLayout(&layoutmiddled);
layouted.addLayout(&layoutbottomed);
windowed.setLayout(&layouted);
/* ******************** Second Window ******************** */
/* ******************** Actions First Window ******************** */
QObject::connect(&buttonetc, &QPushButton::clicked, &windowed, &QWidget::show);
/* ******************** Actions First Window ******************** */
/* ******************** Actions Second Window ******************** */
QObject::connect(&buttonetced, &QPushButton::clicked, [&windowed, &file] {file = QFileDialog::getOpenFileName(&windowed, QObject::tr("Sélectionner un fichier son ..."), "C:/", QObject::tr("Audio (*.mp3)"));});
lined0.setText(Qstring(file));
/* ******************** Actions Second Window ******************** */
return program.exec();
}