A null QString is an uninitialized QString while an empty QString is a QString initialized with an empty string(reference). QString s1; QString s2(“”); if(s1==s2) qDebug()<<“same”;//same else qDebug()<<“not same”; qDebug()<<s1.isNull();//true qDebug()<<s1.isEmpty();//true […]

QTexStream::readLine() function is a convenient function that can read a line from a file at a time. However, you must pay attention to so called new line. You may find […]

QSqlDatabase: QMYSQL driver not loaded

Today, I ran a program that connects to a database, then a window popped up: Meanwhile, the following error appeared on the console: QSqlDatabase: QMYSQL driver not loaded QSqlDatabase: available […]

Qt Creator loads the GDB pretty printers in the following manner. First, it imports the gdbbridge module by running the following gdb command. python from gdbbridge import * The file […]

Some day, you may want to debug qmake, … for fun. How to debug qmake? In the source directory of qmake(c:\Qt5.12.1\5.12.1\Src\qtbase\qmake), you will find a .pro file qmake.pro, which would […]