Improving log messages

Qt offers multiple methods for improving log messages. A good compromise between the result and its complexity is to combine the Qt log type with a custom message pattern.

Qt defines five log types, listed as follows, from the least to the most critical level:

• qDebug(): Custom debug messages
• qInfo(): Informational messages
• qWarning(): Warnings and recoverable errors in your applications
• qCrtical(): Critical error messages and system errors
• qFatal(): Write a last message before automatically exiting

Try to always use the most appropriate option!

By default, the message pattern is configured to only display your message without any extra data, but you can customize the pattern to display more information. This pattern can be changed at runtime by setting the QT_MESSAGE_PATTERN environment variable. You can also call the qSetMessagePattern function from your software to change the pattern. The pattern is just a string, with some placeholders.

The following are the most common...