qt

The qDebug()<<“aaaaa” is working perfectly on Windows, but when I compile the same program on CentOS, it suddenly stops working. I cannot see anything displayed on the console. Why qDebug […]

The random number generation functions are always confusing. We often use the C rand() function to generate an integer number between 0 and RAND_MAX. We call it several times and […]

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 […]

In this post, I talked about the best practice to use forward declaration or include file for a class: only include header files for base class and value member class […]

I used to putting all my code in one .cpp file. That is my style. Don’t be fooled by the “principles” and “theories” advocated by software engineering experts. Those “principles” […]

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 […]

You may wonder why the qmake CONFIG variable has values that you never set. Sometimes, you even need to remove some values from CONFIG in your .pro file using: CONFIG […]

You may never notice the interaction between Qt Creator and the GDB debugger in the past. The communication between Qt Creator and GDB is hidden well. You are supposed to […]

If you got an app that was built with Qt lib, how do you get the version of Qt? Suppose you only have the .exe file, you have not the […]