interface/validate.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        validate.h
   3 // Purpose:     interface of wxValidator
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows license
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     @class wxValidator
  11     @wxheader{validate.h}
  12
  13     wxValidator is the base class for a family of validator classes that mediate
  14     between a class of control, and application data.
  15
  16     A validator has three major roles:
  17
  18     @li to transfer data from a C++ variable or own storage to and from a control;
  19     @li to validate data in a control, and show an appropriate error message;
  20     @li to filter events (such as keystrokes), thereby changing the behaviour of the
  21         associated control.
  22
  23     Validators can be plugged into controls dynamically.
  24
  25     To specify a default, 'null' validator, use the symbol ::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
  31     derive the class from @c wxPyValidator in order to get Python-aware
  32     capabilities for 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     ~wxValidator();
  55
  56     /**
  57         All validator classes must implement the Clone() function, which returns
  58         an identical copy of itself.
  59
  60         This is because validators are passed to control constructors as references
  61         which must be copied. Unlike objects such as pens and brushes, it does not
  62         make sense to have a reference counting scheme to do this cloning, because
  63         all validators should have separate data.
  64
  65         @returns 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     void SetBellOnError(bool doIt = true);
  79
  80     /**
  81         Associates a window with the validator.
  82     */
  83     void SetWindow(wxWindow* window);
  84
  85     /**
  86         This overridable function is called when the value in the window must be
  87         transferred to the validator.
  88
  89         @return @false if there is a problem.
  90     */
  91     virtual bool TransferFromWindow();
  92
  93     /**
  94         This overridable function is called when the value associated with the
  95         validator must be transferred to the window.
  96
  97         @return @false if there is a problem.
  98     */
  99     virtual bool TransferToWindow();
 100
 101     /**
 102         This overridable function is called when the value in the associated window
 103         must be validated.
 104
 105         @return @false if the value in the window is not valid; you may pop up an error
 106                 dialog.
 107     */
 108     virtual bool Validate(wxWindow* parent);
 109 };
 110
 111 /**
 112     An empty wxValidator instance.
 113 */
 114 wxValidator wxDefaultValidator;