wxConfigPathChanger Class Reference

#include <wx/config.h>

Detailed Description

A handy little class which changes the current path in a wxConfig object and restores it in dtor.

Declaring a local variable of this type, it's possible to work in a specific directory and ensure that the path is automatically restored when the function returns.

For example:

// this function loads somes settings from the given wxConfig object;
// the path selected inside it is left unchanged
bool LoadMySettings(wxConfigBase* cfg)
{
    wxConfigPathChanger changer(cfg, "/Foo/Data/SomeString");
    wxString str;
    if ( !config->Read("SomeString", &str) ) {
        wxLogError("Couldn't read SomeString!");
        return false;     
            // NOTE: without wxConfigPathChanger it would be easy to forget to
            //       set the old path back into the wxConfig object before this return!
    }
    
    // do something useful with SomeString...
    
    return true;    // again: wxConfigPathChanger dtor will restore the original wxConfig path
}

Library:  wxBase

Category:  Application and System configuration

Public Member Functions
	wxConfigPathChanger (const wxConfigBase *pContainer, const wxString &strEntry)
	Changes the path of the given wxConfigBase object so that the key strEntry is accessible (for read or write).
	~wxConfigPathChanger ()
	Restores the path selected, inside the wxConfig object passed to the ctor, to the path which was selected when the wxConfigPathChanger ctor was called.
const wxString &	Name () const
	Returns the name of the key which was passed to the ctor.
void	UpdateIfDeleted ()
	This method must be called if the original path inside the wxConfig object (i.e.

Constructor & Destructor Documentation

wxConfigPathChanger::wxConfigPathChanger	(	const wxConfigBase *	pContainer,
		const wxString &	strEntry
	)

Changes the path of the given wxConfigBase object so that the key strEntry is accessible (for read or write).

In other words, the ctor uses wxConfigBase::SetPath() with everything which precedes the last slash of strEntry, so that:

wxConfigPathChanger(wxConfigBase::Get(), "/MyProgram/SomeKeyName");

has the same effect of:

wxConfigPathChanger(wxConfigBase::Get(), "/MyProgram/");

wxConfigPathChanger::~wxConfigPathChanger

(

)

Restores the path selected, inside the wxConfig object passed to the ctor, to the path which was selected when the wxConfigPathChanger ctor was called.

Member Function Documentation

const wxString& wxConfigPathChanger::Name

(

)

const

Returns the name of the key which was passed to the ctor.

The "name" is just anything which follows the last slash of the string given to the ctor.

void wxConfigPathChanger::UpdateIfDeleted

(

)

This method must be called if the original path inside the wxConfig object (i.e.

the current path at the moment of creation of this wxConfigPathChanger object) could have been deleted, thus preventing wxConfigPathChanger from restoring the not existing (any more) path.

If the original path doesn't exist any more, the path will be restored to the deepest still existing component of the old path.