效果图：

http://s13/mw690/b388979b4ced8a2e8075c&690

代码：

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include"QFile.h"
#include"QTextStream.h"
#include            //该对象主要用于非Unicode编码数据与Unicode编码数据之间的转换

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    QTextCodec::setCodecForTr(QTextCodec::codecForName("gb18030"));//见http://blog.csdn.net/dbzhang800/article/details/6615252
    ui->setupUi(this);
    QFile filetmp("Gname.txt");                     //读文件
       filetmp.open(filetmp.ReadOnly|filetmp.Text);
       QTextStream genname(&filetmp);
        ui->comboBox->addItem( tr("选择观测发电机"));
        QVector namevec;
       while (!genname.atEnd())
       {
           QString buf;
           buf=genname.readLine();
//           buf.remove("2H");
//           buf.remove("2L");
//           buf.remove("2M");
//           buf.remove("2J");
           namevec.append(buf);
       }
       for(int i=0;i
       {
           ui->comboBox->addItem(namevec[i]);
       }
}

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

void MainWindow::changeEvent(QEvent *e)
{
    QMainWindow::changeEvent(e);
    switch (e->type()) {
    case QEvent::LanguageChange:
        ui->retranslateUi(this);
        break;
    default:
        break;
    }
}