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Simple-logger

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Revision as of 14:52, 24 March 2016 by Wieland (talk | contribs) (clean-up)
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This code shows as possibly of logging with recording to the file. Also if necessary it is possible show logging information in QPlainTextEdit

Example of using

QPlainTextEdit *editor = new QPlainTextEdit(this);
QString fileName = "c:.txt";
Logger *logger = new Logger(this, fileName, editor);
logger.write("Hello Qt");

Logger.h

#ifndef LOGGER_H
#define LOGGER_H

#include <QObject>
#include <QPlainTextEdit>
#include <QFile>
#include <QTextStream>
#include <QDateTime>

class Logger : public QObject
{
 Q_OBJECT
public:
 explicit Logger(QObject *parent, QString fileName, QPlainTextEdit *editor = 0);
 ~Logger();
 void setShowDateTime(bool value);

private:
 QFile *file;
 QPlainTextEdit *m_editor;
 bool m_showDate;

signals:

public slots:
 void write(const QString &value);

};

#endif // LOGGER_H

Logger.cpp

#include "Logger.h"

Logger::Logger(QObject *parent, QString fileName, QPlainTextEdit *editor) : QObject(parent) {
 m_editor = editor;
 m_showDate = true;
 if (!fileName.isEmpty()) {
  file = new QFile;
  file->setFileName(fileName);
  file->open(QIODevice::Append | QIODevice::Text);
 }
}

void Logger::write(const QString &value) {
 QString text = value;// + "";
 if (m_showDate)
  text = QDateTime::currentDateTime().toString("dd.MM.yyyy hh:mm:ss ") + text;
 QTextStream out(file);
 out.setCodec("UTF-8");
 if (file != 0) {
  out << text;
 }
 if (m_editor != 0)
  m_editor->appendPlainText(text);
}

void Logger::setShowDateTime(bool value) {
 m_showDate = value;
}

Logger::~Logger() {
 if (file != 0)
 file->close();
}