GUI – Save Current Program

Now, that the basic GUI elements are in place, some additional features will be added before beginning work in changing the edit box from a simple text editor into a program editor.  The first feature to add is to have the application save the program file path name that was loaded the last time it was run.  This involves saving the current program path as part of the saved settings.

When the settings are restored, the set current program helper function is called with the restored program name.  The current program member variable can't be set directly because the window title does not get set and a warning message is issued by the Qt routines that there is no '[*]' placeholder in the window title when the program is loaded.  When the program is loaded into the edit box, a document modified signal is sent to the set window modified slot, when then attempts to set the modified flag, but placeholder has not yet been set in the window title.  The helper function takes care of this.

Once the edit box instance has been created, the constructor checks if the current program is not empty.  It then checks if the program file still exists, otherwise the file was either deleted or moved since the last run, so the current program path is cleared.  Also, if there is an error loading the program file, the current program path is cleared.

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