Qt标准对话框之QFileDialog

QString MainWindow::showFileDialog(QFileDialog::AcceptMode mode, QString title){    QString ret = "";    QFileDialog fd(this);        QStringList filters;    filters.append("Text File (*.txt)");    filters.append("All Files (*)");    fd.setWindowTitle(title);    fd.setAcceptMode(QFileDialog::AcceptOpen);      //打开模式    fd.setNameFilters(filters);                     //筛选器    if( mode == QFileDialog::AcceptOpen)    {        fd.setFileMode(QFileDialog::ExistingFile);    }    if( fd.exec() == QFileDialog::Accepted )    {        ret = fd.selectedFiles()[0];    }    return ret;}