This article is based on another article found here on Codeguru : Alerting the user when
an open file has been changed by another application (from Bernd Wib ler).
This article showed us how a CDocument-class can be notified when the file is changed by another application.
My problem is that my CDocument-class is like a projectfile: It has a collection of files. I want my
CDocument-class to be notified if one of these files is changed.
I’ve created a new class called CFileChangeEvent. This class has following methodes :
void addFile(const std::string &sFileName)
Use this method when you want to be notified of changes of a file. When the notification thread is running it will be stopped and restarted.
void removeFile(const std::string &sFileName)Use this method when you don’t want to be notified anymore. When the notification thread is running it will be stopped and restarted.
void startWatch(void)This method starts the notification thread.
void stopWatch(void)This method stops the notification thread. It’s also called in the destructor, so you the thread will allways stop.
virtual void OnFileAlarm(FileAlarm nAlarm, const std::string &sFileName)Override this method. This method is called when a file is changed or deleted. FileAlarm is an enum with following attributes : FA_CHANGED, FA_REMOVED.
How to use this class ?
Derive a class (for example your CDocument-class) from CFileChangeEvent and override the OnFileAlarm. That’s all.
Date Last Updated: May 17, 1999