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         wxIntegerValidator, wxFloatingPointValidator
  43 */
  44 class wxValidator : public wxEvtHandler
  45 {
  46 public:
  47     /**
  48         Constructor.
  49     */
  50     wxValidator();
  51
  52     /**
  53         Destructor.
  54     */
  55     virtual ~wxValidator();
  56
  57     /**
  58         All validator classes must implement the Clone() function, which
  59         returns an identical copy of itself.
  60
  61         This is because validators are passed to control constructors as
  62         references which must be copied. Unlike objects such as pens and
  63         brushes, it does not make sense to have a reference counting scheme to
  64         do this cloning because all validators should have separate data.
  65
  66         @return This base function returns @NULL.
  67     */
  68     virtual wxObject* Clone() const;
  69
  70     /**
  71         Returns the window associated with the validator.
  72     */
  73     wxWindow* GetWindow() const;
  74
  75     /**
  76         This functions switches on or turns off the error sound produced by the
  77         validators if an invalid key is pressed.
  78
  79         @since 2.9.1
  80
  81         @param suppress
  82             If @true, error sound is not played when a validator detects an
  83             error. If @false, error sound is enabled.
  84     */
  85     static void SuppressBellOnError(bool suppress = true);
  86
  87     /**
  88         Associates a window with the validator.
  89
  90         This function is automatically called by wxWidgets when creating a wxWindow-derived
  91         class instance which takes a wxValidator reference.
  92
  93         E.g.
  94         @code
  95         new wxTextCtrl(this, wxID_ANY, wxEmptyString, wxDefaultPosition, wxDefaultSize, 0,
  96                        wxTextValidator(wxFILTER_ALPHA, &g_data.m_string));
  97         @endcode
  98         will automatically link the wxTextValidator instance with the wxTextCtrl
  99         instance.
 100     */
 101     void SetWindow(wxWindow* window);
 102
 103     /**
 104         This overridable function is called when the value in the window must
 105         be transferred to the validator.
 106
 107         @return @false if there is a problem.
 108     */
 109     virtual bool TransferFromWindow();
 110
 111     /**
 112         This overridable function is called when the value associated with the
 113         validator must be transferred to the window.
 114
 115         @return @false if there is a problem.
 116     */
 117     virtual bool TransferToWindow();
 118
 119     /**
 120         This overridable function is called when the value in the associated
 121         window must be validated.
 122
 123         @param parent
 124             The parent of the window associated with the validator.
 125
 126         @return @false if the value in the window is not valid; you may pop up
 127                 an error dialog.
 128     */
 129     virtual bool Validate(wxWindow* parent);
 130 };
 131
 132 /**
 133     An empty, "null" wxValidator instance.
 134 */
 135 const wxValidator wxDefaultValidator;
 136