interface/wx/validate.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        validate.h
   3 // Purpose:     interface of wxValidator
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows licence
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     @class wxValidator
  11
  12     wxValidator is the base class for a family of validator classes that
  13     mediate between a class of control, and application data.
  14
  15     A validator has three major roles:
  16
  17     -#  To transfer data from a C++ variable or own storage to and from a
  18         control.
  19     -#  To validate data in a control, and show an appropriate error message.
  20     -#  To filter events (such as keystrokes), thereby changing the behaviour
  21         of the associated control.
  22
  23     Validators can be plugged into controls dynamically.
  24
  25     To specify a default, "null" validator, use ::wxDefaultValidator.
  26
  27     For more information, please see @ref overview_validator.
  28
  29     @beginWxPythonOnly
  30     If you wish to create a validator class in wxPython you should derive the
  31     class from @c wxPyValidator in order to get Python-aware capabilities for
  32     the various virtual methods.
  33     @endWxPythonOnly
  34
  35     @library{wxcore}
  36     @category{validator}
  37
  38     @stdobjects
  39     ::wxDefaultValidator
  40
  41     @see @ref overview_validator, wxTextValidator, wxGenericValidator
  42 */
  43 class wxValidator : public wxEvtHandler
  44 {
  45 public:
  46     /**
  47         Constructor.
  48     */
  49     wxValidator();
  50
  51     /**
  52         Destructor.
  53     */
  54     virtual ~wxValidator();
  55
  56     /**
  57         All validator classes must implement the Clone() function, which
  58         returns an identical copy of itself.
  59
  60         This is because validators are passed to control constructors as
  61         references which must be copied. Unlike objects such as pens and
  62         brushes, it does not make sense to have a reference counting scheme to
  63         do this cloning because all validators should have separate data.
  64
  65         @return This base function returns @NULL.
  66     */
  67     virtual wxObject* Clone() const;
  68
  69     /**
  70         Returns the window associated with the validator.
  71     */
  72     wxWindow* GetWindow() const;
  73
  74     /**
  75         This functions switches on or turns off the error sound produced by the
  76         validators if an invalid key is pressed.
  77
  78         @since 2.9.1
  79
  80         @param suppress
  81             If @true, error sound is not played when a validator detects an
  82             error. If @false, error sound is enabled.
  83     */
  84     static void SuppressBellOnError(bool suppress = true);
  85
  86     /**
  87         Associates a window with the validator.
  88
  89         This function is automatically called by wxWidgets when creating a wxWindow-derived
  90         class instance which takes a wxValidator reference.
  91
  92         E.g.
  93         @code
  94         new wxTextCtrl(this, wxID_ANY, wxEmptyString, wxDefaultPosition, wxDefaultSize, 0,
  95                        wxTextValidator(wxFILTER_ALPHA, &g_data.m_string));
  96         @endcode
  97         will automatically link the wxTextValidator instance with the wxTextCtrl
  98         instance.
  99     */
 100     void SetWindow(wxWindow* window);
 101
 102     /**
 103         This overridable function is called when the value in the window must
 104         be transferred to the validator.
 105
 106         @return @false if there is a problem.
 107     */
 108     virtual bool TransferFromWindow();
 109
 110     /**
 111         This overridable function is called when the value associated with the
 112         validator must be transferred to the window.
 113
 114         @return @false if there is a problem.
 115     */
 116     virtual bool TransferToWindow();
 117
 118     /**
 119         This overridable function is called when the value in the associated
 120         window must be validated.
 121
 122         @param parent
 123             The parent of the window associated with the validator.
 124
 125         @return @false if the value in the window is not valid; you may pop up
 126                 an error dialog.
 127     */
 128     virtual bool Validate(wxWindow* parent);
 129 };
 130
 131 /**
 132     An empty, "null" wxValidator instance.
 133 */
 134 const wxValidator wxDefaultValidator;
 135