C++ QT图片查看器

private:QList<QString> fs;int i;void MainWindow::on_btnSlt_clicked()
{QStringList files = QFileDialog::getOpenFileNames(this,"选择图片",".","Images(*.png *.jpg *.bmp)");qDebug()<<files;ui->picList->clear();ui->picList->appendPlainText(files.join("\n"));fs = files;ui->labelPic->setPixmap(QPixmap(fs[0]));
}void MainWindow::on_btnPs_clicked()
{i--;if(i<0){i = 0;}ui->labelPic->setPixmap(QPixmap(fs[i]));
}void MainWindow::on_btnNt_clicked()
{i++;if(i == fs.length()){i = fs.length()-1;}ui->labelPic->setPixmap(QPixmap(fs[i]));
}