1直接采用setStyleSheet方法

   不再赘述。类似css

2加载资源文件，用setObjectName设置

A、css文件保留样式，eg:

QPushButton#btLogin {
    min-height: 28px;
    max-height: 48px;
    min-width: 100px;
    max-width: 100px;
    font-weight: 500;
    color: white;
    border:1px solid #0C1686;
    border-radius: 4px;
    background-color: #0C1686;
}

QPushButton#btLogin:hover:!pressed {
    background-color: #0F1BAE;
}

QPushButton#btLogin:pressed {
    background-color: #090F60;
}

B、设置样式

    // 样式
    QFile *file;
    if (QFile::exists("style.css"))
    {
        file = new QFile("style.css");
    }
    else
    {
        file = new QFile(":/style/style.css");
        qDebug()<<"open failed =!";
    }
    file->open(QIODevice::ReadOnly | QIODevice::Text);
    QTextStream stream(file);
    stream.setCodec(QTextCodec::codecForName("UTF-8"));
    QString style = stream.readAll();
    this->setStyleSheet(style); //子窗口去继承
    file->close();
    file->deleteLater();

    pushBtn->setObjectName("btLogin");