DDXFolder & CChooseDirDlg v1.48

For developers who use MFC this is a freeware control which subclasses an edit control to allow you to easily specify a directory/folder. When the edit control is correctly setup it will look like:

The button beside the edit control sports a tooltip when the button is over it and when the button is hit, the following dialog is displayed:

In addition the control integrates with the AutoCompletion functionality of Windows, so that a drop down list appears underneath the edit control which allows the user to quickly select a specific folder. The code is most useful when you want to specify a folder from somewhere in the user interface such as specifying a directory where a bunch of output files will be placed..

Features

• Simple DDX and DDV function which you can use in your MFC code.
• Stand alone directory picker class is also included.
• All the code is fully UNICODE compliant.
• A simple test app is included.

Copyright

• You are allowed to include the source code in any product (commercial, shareware, freeware or otherwise) when your product is released in binary form.
• You are allowed to modify the source code in any way you want except you cannot modify the copyright details at the top of each module.
• If you want to distribute source code with your application, then you are only allowed to distribute versions released by the author. This is to maintain a single distribution point for the source code.

Usage

• To use DDXFolder in your project simply include DDXFolder.cpp and ChooseDirDlg.cpp, and the IDS_DDXFOLDER_* and IDP_DDXFOLDER_* string resources from the test application in your application. Then #include DDXFolder.h or ChooseDirDlg.h in which ever of your modules requires it and make the appropriate calls. Included is a simple dialog based application which shows how to use it. Basically all you need to do is add to your DoDataExchange function as follows:

void CTestgetfolderDlg::DoDataExchange(CDataExchange* pDX)

{
  //Let the base class do its thing

  CDialog::DoDataExchange(pDX);
 

  DDX_FolderControl(pDX, IDC_FOLDER, m_ctrlGetFolder);

}

• The auto completion functionality uses the ACLO_FILESYSDIRS enum value of IACList2::SetOptions to show auto completion for folders. This means that auto completion is only supported on Internet Explorer 6 or later.
• As of v1.33, the code now uses ATL's CComPtr class for its internal usage of the AutoCompletion functionality. This does mean that for MFC only client projects, you will need to add ATL support to your project.
• As of v1.43 the classes are now designed for VC 2017 or later. They will not compile on earlier releases of VC.
• As of v1.42 the class CChooseDirDlg uses the IFileDialog COM interface which requires Windows Vista or later.

History

v1.48 (2 April 2022)

• Updated copyright details.
• Updated the code to use C++ uniform initialization for all variable declarations.

v1.47 (3 May 2020)

• Fixed more Clang-Tidy static code analysis warnings in the code.

v1.46 (14 March 2020)

• Updated copyright details.
• Fixed more Clang-Tidy static code analysis warnings in the code.

v1.45 (20 December 2019)

• Fixed various Clang-Tidy static code analysis warnings in the code.

v1.44 (18 May 2019)

• Updated copyright details.
• Updated the code to clean compile on VC 2019

v1.43 (8 July 2018)

• Updated copyright details.
• Fixed a number of C++ core guidelines compiler warnings. These changes mean that the code will now only compile on VC 2017 or later.

v1.42 (23 September 2017)

• Updated copyright details.
• Replaced CString::operator LPC*STR() calls throughout the codebase with CString::GetString calls.
• Replaced NULL throughout the codebase with nullptr. This means that the minimum requirement for the framework is now VC 2010.
• Reworked the code in CGetFolderControl::InitializeAutoComplete to use ATL::CComPtr::CoCreateInstance.
• Reworked the CChooseDirDlg class to use IFileDialog interface.
• All the code has had SAL annotations added.

v1.41 (12 November 2015)

• Verified the code compiles cleanly on VC 2015.
• Updated the sample apps main icon.
• Updated copyright details.

v1.40 (23 December 2014)

• If the main edit control is now hidden, the buddy buttton is now also hidden. The corrolary of if the main edit control is now shown, then the buddy button is now also shown. Thanks to Rene Laviolette for requesting this update.

v1.39 (1 March 2014)

• Updated copyright details.
• Updated MFC message maps in sample app and in DDXFile module to use C++ standard for pointers to member methods.
• Reworked DDX_FolderControl to use DDX_Control for most of its functionality
• Updated the code to clean compile on VC 2013 & 2012.
• Updated the code to clean compile using /analyze 

v1.38 (10 September 2011)

• Updated copyright details.
• Verified code compiles cleanly on VC 2010
• Fixed an access violation bug in CDDXFolderModifyButton::PreTranslateMessage if the IDS_DDXFOLDER_EDIT_TEXT string resource is not loaded

21 December 2008

• Minor update to documentation, screen captures and names of variables in DDX / DDV functions.

v1.37 (18 December 2008)

• Updated copyright details.
• InitializeAutoComplete now returns a HRESULT instead of a BOOL
• DDV_FolderControlNotFile function has been renamed to DDV_FolderControlIsFolder
• Removed VC 6 style AppWizard comments from the code
• The code has now been updated to support VC 2005 or later only
• Code now compiles cleanly using Code Analysis (/analyze)
• Refactored the CChooseDirDlg codebase quite a bit
• Updated DDX_FolderControl code to be consistent with DDX_Control in VC 2008

v1.36 (21 November 2007)

• The code now uses the value 32 instead of the enum ACLO_FILESYSDIRS in the call to IID_IACList2::SetOptions. This is because newer versions of the Windows SDK make this value dependent on the setting of the _WIN32_IE preprocessor macros. Thanks to Alexey Kuznetsov for reporting this issue.

v1.35 (19 November 2007)

• Minor update to display HRESULT's correctly.
• Minor tidy up to remove old style AppWizard comments

v1.34 (25 August 2006)

• Minor update to the name of one of the string resources used by DDXFolder

v1.33 (19 August 2006)

• Control now takes advantage of the AutoCompletion functionality (IAutoComplete et al) built into Windows to improve the UI experience. If enabled then a drop down list will appear underneath the edit control which allows the user to quickly select a specific folder. The code uses the COM interfaces (IAutoComplete) to AutoCompletion instead of the more simplified functionality provided by SHAutoComplete. This allows the code to customize the auto completion UI so that only file system folders are selectable.

v1.32 (11 August 2006)

• Reworked all the use of string resources. Now all the string resources used by the control are all loaded in one single virtual function. In addition if you do not want to use inheritance, all the strings can be customized via Get/Set methods.
• Broke the DDV functionality into seperate discreet DDV functions
• The dialog control id of the edit button can now be specified via the SubclassEdit and DDX_FilenameControl functions

v1.31 (29 July 2006)

• Initial enabled state of the edit control is now reflected into the edit button when AddEditButton is called.

v1.30 (19 July 2006)

• Updated copyright details.
• Updated documentation to use the same style as the web site.
• Addition of a CCHOOSEDIRDLG_EXT_CLASS preprocessor macro to allow the code to be easily added to an extension dll.
• Addition of a CDDXFOLDER_EXT_CLASS preprocessor macro to allow the code to be easily added to an extension dll.
• Optimized CDDXFolderModifyButton constructor code
• Removed support for the old style directory picker dialog which used a modified version of the File Open dialog.
• Changed the names of the constants used for DDV_FolderControl
• Added support for a DDXGETFOLDER_FOLDERMUSTEXIST flag
• Removed the GetFolder and SetFolder methods as they are not really required
• Verified code clean compiles in VC2005

v1.29 (9 January 2003)

• Updated copyright details.
• Changed a class name from "CModifyButton" to the better named "CDDXFileModifyButton".
• Enabled state of control is now reflected to buddy button edit control. Thanks to "matro" for pointing out this problem.
• Made the "CGetFolderControl::Edit" virtual for easier customisation.
• Made all strings used by the classes easier to modify by making them virtual methods of the class
• Made the "CGetFolderControl::AddEditButton" method virtual for easier customisation.

v1.28 (24 May 2001)

• Fixed a problem with the Z-Order of the control being set incorrectly
• Updated copyright message.

v1.27 (18 July 2000)

• Removed an unreferenced variable from the demo app module "testgetfolderDlg.cpp"
• Width of the edit button is now determined from the text which it displays.

v1.26 (17 May 2000)

• The width of the underlying edit control is now shrunk when the "..." button is created. This makes layout of the control using the resource designer a lot simpler.

v1.25 (14 May 2000)

• The "..." button now supports being tabbed into i.e. the WS_TABSTOP style

v1.23 (3 April 1999)

• Fixed another resource compiler problem.
• Updated the copyright messages.
• General code tidy up.

7 February 1999

• Minor bug fix in choosedirdlg.cpp.

v1.22 (30 September 1998)

• Fixed a compiler problem in the rc file. I was accidentally shipping the wrong resource.h file.

v1.21 (17 September 1998)

• Minor update to some code comments and the online documentation.

v1.2 (16 September 1998)

• Updated all the documentation to be HTML based as with my other shareware / freeware.
• Unicode enabled all the code and provision of Unicode build configurations.
• VC 5 mak files provided now as standard
• Provision of a DDV function.
• General tidy up of the sample app including removing all the AppWizard generated comments.
• All code now compiles cleanly at warning level 4.
• Replaced all TRACE0 calls with TRACE.
• Changed name of main function from DDX_GetFolder to DDX_FolderControl.
• Module name has been changed from ddxgetfolder to ddxfolder.
• Sample app now allows read only state of widget to be toggled.
• Addition of a DDX_FolderValue function.
• Change the ID's of the strings in the resource table which the code uses.

v1.1 (26 November 1997)

• Used internally by ddxgetfolder is another class which you may find helpful. It's name is CChooseDirDlg which implements a standalone directory picker dialog which can be used independently of the DDX/DDV functions.

API Reference

The following functions are provided:

CChooseDirDlg::DoModal
DDX_FolderControl
DDX_FolderValue
DDV_FolderControlIsFolder
DDV_FolderControlMustExist
DDV_FolderControlOverwritePrompt
DDV_FolderNotEmpty

CChooseDirDlg::DoModal

HRESULT DoModal(CString& sDir);

Return Value

A standard COM error code. S_OK if successful.

Parameters

sDir is used to set the initial directory and upon return contains the newly selected directory.

Remarks

Internally this function is called when you click on the "..." button on the UI. You are free to use this class independently of the DDX / DDV code to call up a directory picker dialog in your own code.

DDX_FolderControl

BOOL DDX_FolderControl(CDataExchange* pDX, int nIDC, CGetFolderControl& rControl, UINT nModifyButton = 0xFFFFFFFF);

Parameters

pDX is the usual CDataExchange object which will be passed into your DoDataExchange function.

nIDC is the dialog ID of the edit control to subclass.

rControl will contain upon return the window control which manages the compound edit and button controls.

nModifyButtonID is a control id of the modify button.

Remarks

Associates an existing edit control with dialog ID nIDC to a compound folder picker control. Normally you would calls to this function in your dialog class's DoDataExchange member function. The function returns TRUE if the setup of the edit control succeeded otherwise FALSE is returned.

DDX_FolderValue

void DDX_FolderValue(CDataExchange* pDX, CGetFolderControl& rControl, CString& sFolder);

Parameters

pDX is the usual CDataExchange object which will be passed into your DoDataExchange function.

rControl is the folder control to get or set the directory for.

sFolder is the actual folder to get or set into the control depending on the direction of data exchange occurring .

DDV_FolderControlIsFolder

void DDV_FolderControlIsFolder(CDataExchange* pDX, const CGetFolderControl& rControl, UINT nFailureResourceID, UINT nHelpID = 0xFFFFFFFF);

Parameters

pDX is the usual CDataExchange object which will be passed into your DoDataExchange function.

rControl is the folder control to validate for.

nFailureResourceID is the resource id of the string which will be displayed as a failure message.

nHelpID is the help context ID for the message.

Remarks

This DDV function ensures that the value selected specifies a folder (as opposed to a file).

DDV_FolderControlMustExist

void DDV_FolderControlMustExist(CDataExchange* pDX, const CGetFolderControl& rControl, UINT nFailureResourceID, UINT nHelpID = 0xFFFFFFFF);

Parameters

pDX is the usual CDataExchange object which will be passed into your DoDataExchange function.

rControl is the folder control to validate for.

nFailureResourceID is the resource id of the string which will be displayed as a failure message.

nHelpID is the help context ID for the message.

Remarks

This DDV function ensures that the value selected specifies an existing folder.

DDV_FolderControlOverwritePrompt

void DDV_FolderControlOverwritePrompt(CDataExchange* pDX, CGetFolderControl& rControl, UINT nHelpID = 0xFFFFFFFF);

Parameters

pDX is the usual CDataExchange object which will be passed into your DoDataExchange function.

rControl is the folder control to validate for.

nHelpID is the help context ID for the message.

Remarks

This DDV function prompts the user if an overwrite is allowable if the folder already exists. Validation fails if the end user selects No to the message.

DDV_FolderControlNotEmpty

void DDV_FolderControlNotEmpty(CDataExchange* pDX, const CGetFolderControl& rControl, UINT nFailureResourceID, UINT nHelpID = 0xFFFFFFFF);

Parameters

pDX is the usual CDataExchange object which will be passed into your DoDataExchange function.

rControl is the folder control to validate for.

nFailureResourceID is the resource id of the string which will be displayed as a failure message.

nHelpID is the help context ID for the message.

Remarks

This DDV function ensures that the value selected is not an empty string.

Contacting the Author

PJ Naughter
Email: pjna@naughter.com
Web: http://www.naughter.com
2 April 2022