use wxEmptyString as default value to return from GetAttribute()

[wxWidgets.git] / interface / filedlg.h

/////////////////////////////////////////////////////////////////////////////
// Name:        filedlg.h
// Purpose:     interface of wxFileDialog
// Author:      wxWidgets team
// RCS-ID:      $Id$
// Licence:     wxWindows license
/////////////////////////////////////////////////////////////////////////////

/**
    @class wxFileDialog
    @wxheader{filedlg.h}

    This class represents the file chooser dialog.

    @beginStyleTable
    @style{wxFD_DEFAULT_STYLE}:
           Equivalent to wxFD_OPEN.
    @style{wxFD_OPEN}:
           This is an open dialog; usually this means that the default
           button's label of the dialog is "Open". Cannot be combined with
           wxFD_SAVE.
    @style{wxFD_SAVE}:
           This is a save dialog; usually this means that the default button's
           label of the dialog is "Save". Cannot be combined with wxFD_OPEN.
    @style{wxFD_OVERWRITE_PROMPT}:
           For save dialog only: prompt for a confirmation if a file will be
           overwritten.
    @style{wxFD_FILE_MUST_EXIST}:
           For open dialog only: the user may only select files that actually
           exist.
    @style{wxFD_MULTIPLE}:
           For open dialog only: allows selecting multiple files.
    @style{wxFD_CHANGE_DIR}:
           Change the current working directory to the directory where the
           file(s) chosen by the user are.
    @style{wxFD_PREVIEW}:
           Show the preview of the selected files (currently only supported by
           wxGTK using GTK+ 2.4 or later).
    @endStyleTable

    @library{wxcore}
    @category{cmndlg}

    @see @ref overview_wxfiledialogoverview "wxFileDialog overview",
    wxFileSelector()
*/
class wxFileDialog : public wxDialog
{
public:
    /**
        Constructor. Use ShowModal() to show the dialog.

        @param parent
            Parent window.
        @param message
            Message to show on the dialog.
        @param defaultDir
            The default directory, or the empty string.
        @param defaultFile
            The default filename, or the empty string.
        @param wildcard
            A wildcard, such as "*.*" or "BMP files (*.bmp)|*.bmp|GIF files
        (*.gif)|*.gif".
            Note that the native Motif dialog has some limitations with respect to
            wildcards; see the Remarks section above.
        @param style
            A dialog style. See wxFD_* styles for more info.
        @param pos
            Dialog position. Not implemented.
        @param size
            Dialog size. Not implemented.
        @param name
            Dialog name. Not implemented.
    */
    wxFileDialog(wxWindow* parent,
                 const wxString& message = "Choose a file",
                 const wxString& defaultDir = "",
                 const wxString& defaultFile = "",
                 const wxString& wildcard = ".",
                 long style = wxFD_DEFAULT_STYLE,
                 const wxPoint& pos = wxDefaultPosition,
                 const wxSize& sz = wxDefaultSize,
                 const wxString& name = "filedlg");

    /**
        Destructor.
    */
    ~wxFileDialog();

    /**
        Returns the default directory.
    */
    wxString GetDirectory() const;

    /**
        If functions
        SetExtraControlCreator()
        and ShowModal() were called,
        returns the extra window. Otherwise returns @NULL.
    */
    wxWindow* GetExtraControl() const;

    /**
        Returns the default filename.
    */
    wxString GetFilename() const;

    /**
        Fills the array @a filenames with the names of the files chosen. This
        function should only be used with the dialogs which have @c wxFD_MULTIPLE style,
        use GetFilename() for the others.
        Note that under Windows, if the user selects shortcuts, the filenames
        include paths, since the application cannot determine the full path
        of each referenced file by appending the directory containing the shortcuts
        to the filename.
    */
    void GetFilenames(wxArrayString& filenames) const;

    /**
        Returns the index into the list of filters supplied, optionally, in the
        wildcard parameter.
        Before the dialog is shown, this is the index which will be used when the
        dialog is first displayed.
        After the dialog is shown, this is the index selected by the user.
    */
    int GetFilterIndex() const;

    /**
        Returns the message that will be displayed on the dialog.
    */
    wxString GetMessage() const;

    /**
        Returns the full path (directory and filename) of the selected file.
    */
    wxString GetPath() const;

    /**
        Fills the array @a paths with the full paths of the files chosen. This
        function should only be used with the dialogs which have @c wxFD_MULTIPLE style,
        use GetPath() for the others.
    */
    void GetPaths(wxArrayString& paths) const;

    /**
        Returns the file dialog wildcard.
    */
    wxString GetWildcard() const;

    /**
        Sets the default directory.
    */
    void SetDirectory(const wxString& directory);

    /**
        Customize file dialog by adding extra window, which is typically placed
        below the list of files and above the buttons.
        SetExtraControlCreator can be called only once, before calling
        ShowModal().
        The @c creator function should take pointer to parent window (file dialog)
        and should return a window allocated with operator new.
        Supported platforms: wxGTK, wxUniv.
    */
    bool SetExtraControlCreator(t_extraControlCreator creator);

    /**
        Sets the default filename.
    */
    void SetFilename(const wxString& setfilename);

    /**
        Sets the default filter index, starting from zero.
    */
    void SetFilterIndex(int filterIndex);

    /**
        Sets the message that will be displayed on the dialog.
    */
    void SetMessage(const wxString& message);

    /**
        Sets the path (the combined directory and filename that will be returned when
        the dialog is dismissed).
    */
    void SetPath(const wxString& path);

    /**
        Sets the wildcard, which can contain multiple file types, for example:
        "BMP files (*.bmp)|*.bmp|GIF files (*.gif)|*.gif"
        Note that the native Motif dialog has some limitations with respect to
        wildcards; see the Remarks section above.
    */
    void SetWildcard(const wxString& wildCard);

    /**
        Shows the dialog, returning wxID_OK if the user pressed OK, and wxID_CANCEL
        otherwise.
    */
    int ShowModal();
};



// ============================================================================
// Global functions/macros
// ============================================================================

/** @ingroup group_funcmacro_dialog */
//@{

/**
    Pops up a file selector box. In Windows, this is the common file selector
    dialog. In X, this is a file selector box with the same functionality. The
    path and filename are distinct elements of a full file pathname. If path
    is empty, the current directory will be used. If filename is empty, no
    default filename will be supplied. The wildcard determines what files are
    displayed in the file selector, and file extension supplies a type
    extension for the required filename. Flags may be a combination of
    wxFD_OPEN, wxFD_SAVE, wxFD_OVERWRITE_PROMPT or wxFD_FILE_MUST_EXIST.

    @note wxFD_MULTIPLE can only be used with wxFileDialog and not here since
          this function only returns a single file name.

    Both the Unix and Windows versions implement a wildcard filter. Typing a
    filename containing wildcards (*, ?) in the filename text item, and
    clicking on Ok, will result in only those files matching the pattern being
    displayed.

    The wildcard may be a specification for multiple types of file with a
    description for each, such as:

    @code
    "BMP files (*.bmp)|*.bmp|GIF files (*.gif)|*.gif"
    @endcode

    The application must check for an empty return value (the user pressed
    Cancel). For example:

    @code
    wxString filename = wxFileSelector("Choose a file to open");
    if ( !filename.empty() )
    {
        // work with the file
        ...
    }
    //else: cancelled by user
    @endcode

    @header{wx/filedlg.h}
*/
wxString wxFileSelector(const wxString& message,
                        const wxString& default_path = "",
                        const wxString& default_filename = "",
                        const wxString& default_extension = "",
                        const wxString& wildcard = ".",
                        int flags = 0,
                        wxWindow* parent = NULL,
                        int x = -1,
                        int y = -1);

//@}