人，技术，生活。
1 2 3 4 5 6 | // ui->btnEdit is a QLabel. ui->btnEdit->setText(QString("<a href=\"localhost\"><font color=\"#ff0000\">") + tr("Edit") + QString("</font></a>")); ui->btnEdit->setAlignment(Qt::AlignLeft | Qt::AlignVCenter); connect(ui->btnEdit, &QLabel::linkActivated, [=, this](QString url) { ... }); |
refer to:
https://www.lmlphp.com/user/507/article/item/13949
1 2 3 4 5 6 7 8 9 | telnet 192.168.1.165 3306 # firewall in ubuntu sudo ufw disable # or found ip changed vi /etc/mysql/mysql.conf.d/mysqld.cnf systemctl restart mysql systemctl status mysql |
refer to:
https://blog.csdn.net/zhangasas/article/details/89432832
1 2 3 4 5 6 7 8 | 1452-1519 Leonardo da Vinci 达芬奇 1473-1543 Mikołaj Kopernik 哥白尼 1564-1642 Galileo 伽利略 1596-1650 René Descartes 笛卡尔 1643-1727 Isaac Newton 牛顿 1707-1783 Leonhard Euler 欧拉 1736-1813 Joseph-Louis Lagrange 拉格朗日 1789 法国大革命 |
QString gst_str = QString("filesrc location=\"%1\" ! qtdemux ! h265parse ! nvh265dec ! videoconvert ! appsink").arg(mp4_file_path.c_str());
m_video.reset(new cv::VideoCapture(gst_str.toStdString().c_str(), cv::CAP_GSTREAMER));
refer to:
https://blog.csdn.net/jiexijihe945/article/details/125928135
https://qa.1r1g.com/sf/ask/945062541/
http://www.jsxyy.com.cn/voddetail/185181.html
1 2 3 | #include <signal.h> signal(SIGPIPE, SIG_IGN); //. |
And reconnect mysql database before wait_timeout reached.
refer to:
https://zhuanlan.zhihu.com/p/335138654
https://blog.csdn.net/chengcheng1024/article/details/108104507
https://zhuanlan.zhihu.com/p/36104903
1 2 3 4 5 6 7 | ffmpeg -f dshow -list_devices true -i dummy #can only play one instance simultaneously ffplay -f dshow -i video="Integrated Webcam" #can play multiple instances at once ffmpeg -f dshow -i audio="Microphone (Realtek(R) Audio)" out2.wav |
refer to:
https://blog.csdn.net/qq_43627907/article/details/124416450
compiled ok in Qt5.15.2.
https://blog.csdn.net/how0723/article/details/77418421
https://zhuanlan.zhihu.com/p/31348306
search 'QAudioOutput' in Qt Creator Examples.
https://blog.csdn.net/jlf521521/article/details/106689503
QT5 使用QCustomplot绘制频谱瀑布图并封快速傅里叶变换fft类
https://blog.csdn.net/u013915524/article/details/122288358
Need to set the time line execution curve as linear.
1 2 3 4 5 | m_time_line.reset(new QTimeLine(m_span_msecs * count, this)); m_time_line->setFrameRange(0, count); m_time_line->setEasingCurve(QEasingCurve::Linear); // below is deprecated //m_time_line->setCurveShape(QTimeLine::LinearCurve); |
Different keywords
1 2 3 | sqlite mysql AUTOINCREMENT AUTO_INCREMENT (datetime('now','localtime')) now() |
refer to:
https://doc.qt.io/qtforpython-6.2/overviews/sql-types.html
https://blog.csdn.net/zhangjianangyou/article/details/117018024
1 2 3 4 5 6 7 8 | class A1 { ~A1(); ... B1 m_b1; C1 m_c1; D1 m_d1; }; |
Through practice in gcc, I found the deletion order of class A1 is: ~A1(), m_d1, m_c1, m_b1, ...
Don't call QGridLayout::itemAtPosition.
Like this,
1 2 3 4 5 6 7 8 9 10 11 12 | for (int i = 0; i < grid_layout->count(); i++) { QLayoutItem* item = grid_layout->itemAt(i); if (item->widget() == widget_wanted) { int row, column, row_span, column_span; grid_layout->getItemPosition(i, &row, &column, &row_span, &column_span); // grid_layout->addWidget(frame, row, column); } } |