interface/cshelp.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        cshelp.h
   3 // Purpose:     interface of wxHelpProvider
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows license
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9 /**
  10     @class wxHelpProvider
  11     @wxheader{cshelp.h}
  12
  13     wxHelpProvider is an abstract class used by a program implementing
  14     context-sensitive help to show the help text for the given window.
  15
  16     The current help provider must be explicitly set by the application using
  17     wxHelpProvider::Set().
  18
  19     @library{wxcore}
  20     @category{help}
  21
  22     @see wxContextHelp, wxContextHelpButton, wxSimpleHelpProvider,
  23          wxHelpControllerHelpProvider, wxWindow::SetHelpText(),
  24          wxWindow::GetHelpTextAtPoint()
  25 */
  26 class wxHelpProvider
  27 {
  28 public:
  29     /**
  30         Virtual destructor for any base class.
  31     */
  32     ~wxHelpProvider();
  33
  34     /**
  35         Associates the text with the given window.
  36
  37         @remarks
  38         Although all help providers have these functions to allow making
  39         wxWindow::SetHelpText() work, not all of them implement the functions.
  40     */
  41     virtual void AddHelp(wxWindowBase* window, const wxString& text);
  42
  43     /**
  44         Associates the text with the given ID.
  45
  46         This help text will be shown for all windows with ID @a id, unless they
  47         have more specific help text associated using the other AddHelp()
  48         prototype.  May be used to set the same help string for all Cancel
  49         buttons in the application, for example.
  50
  51         @remarks
  52         Although all help providers have these functions to allow making
  53         wxWindow::SetHelpText() work, not all of them implement the functions.
  54     */
  55     virtual void AddHelp(wxWindowID id, const wxString& text);
  56
  57     /**
  58         Returns pointer to help provider instance.
  59
  60         Unlike some other classes, the help provider is not created on demand.
  61         This must be explicitly done by the application using Set().
  62     */
  63     static wxHelpProvider* Get();
  64
  65     /**
  66         This version associates the given text with all windows with this id.
  67         May be used to set the same help string for all Cancel buttons in
  68         the application, for example.
  69     */
  70     virtual wxString GetHelp(const wxWindowBase* window);
  71
  72
  73     /**
  74         Removes the association between the window pointer and the help text.
  75         This is called by the wxWindow destructor. Without this, the table of
  76         help strings will fill up and when window pointers are reused, the
  77         wrong help string will be found.
  78     */
  79     virtual void RemoveHelp(wxWindowBase* window);
  80
  81     /**
  82         Set the current, application-wide help provider.
  83
  84         @return Pointer to previous help provider or @NULL if there wasn't any.
  85     */
  86     static wxHelpProvider* Set(wxHelpProvider* helpProvider);
  87
  88     /**
  89         Shows help for the given window.
  90
  91         Override this function if the help doesn't depend on the exact position
  92         inside the window, otherwise you need to override ShowHelpAtPoint().
  93         Returns @true if help was shown, or @false if no help was available for
  94         this window.
  95     */
  96     virtual bool ShowHelp(wxWindowBase* window);
  97
  98     /**
  99         This function may be overridden to show help for the window when it
 100         should depend on the position inside the window, By default this method
 101         forwards to ShowHelp(), so it is enough to only implement the latter if
 102         the help doesn't depend on the position.  Returns @true if help was
 103         shown, or @false if no help was available for this window.
 104
 105         @param window
 106             Window to show help text for.
 107         @param point
 108             Coordinates of the mouse at the moment of help event emission.
 109         @param origin
 110             Help event origin, see wxHelpEvent::GetOrigin.
 111     */
 112     virtual bool ShowHelpAtPoint(wxWindowBase* window, const wxPoint point,
 113                                  wxHelpEvent::Origin origin);
 114 };
 115
 116
 117
 118 /**
 119     @class wxHelpControllerHelpProvider
 120     @wxheader{cshelp.h}
 121
 122     wxHelpControllerHelpProvider is an implementation of wxHelpProvider which
 123     supports both context identifiers and plain text help strings. If the help
 124     text is an integer, it is passed to wxHelpController::DisplayContextPopup.
 125     Otherwise, it shows the string in a tooltip as per wxSimpleHelpProvider. If
 126     you use this with a wxCHMHelpController instance on windows, it will use
 127     the native style of tip window instead of wxTipWindow.
 128
 129     You can use the convenience function wxContextId() to convert an integer
 130     context id to a string for passing to wxWindow::SetHelpText().
 131
 132     @library{wxcore}
 133     @category{help}
 134
 135     @see wxHelpProvider, wxSimpleHelpProvider, wxContextHelp,
 136          wxWindow::SetHelpText(), wxWindow::GetHelpTextAtPoint()
 137 */
 138 class wxHelpControllerHelpProvider : public wxSimpleHelpProvider
 139 {
 140 public:
 141     /**
 142         Note that the instance doesn't own the help controller. The help
 143         controller should be deleted separately.
 144     */
 145     wxHelpControllerHelpProvider(wxHelpControllerBase* hc = NULL);
 146
 147     /**
 148         Returns the help controller associated with this help provider.
 149     */
 150     wxHelpControllerBase* GetHelpController() const;
 151
 152     /**
 153         Sets the help controller associated with this help provider.
 154     */
 155     void SetHelpController(wxHelpControllerBase* hc);
 156 };
 157
 158
 159
 160 /**
 161     @class wxContextHelp
 162     @wxheader{cshelp.h}
 163
 164     This class changes the cursor to a query and puts the application into a
 165     'context-sensitive help mode'.  When the user left-clicks on a window
 166     within the specified window, a wxEVT_HELP event is sent to that control,
 167     and the application may respond to it by popping up some help.
 168
 169     For example:
 170     @code
 171     wxContextHelp contextHelp(myWindow);
 172     @endcode
 173
 174     There are a couple of ways to invoke this behaviour implicitly:
 175
 176     - Use the wxDIALOG_EX_CONTEXTHELP style for a dialog (Windows only). This
 177       will put a question mark in the titlebar, and Windows will put the
 178       application into context-sensitive help mode automatically, with further
 179       programming.
 180
 181     - Create a wxContextHelpButton, whose predefined behaviour is
 182       to create a context help object.  Normally you will write your application
 183       so that this button is only added to a dialog for non-Windows platforms
 184       (use wxDIALOG_EX_CONTEXTHELP on Windows).
 185
 186     Note that on Mac OS X, the cursor does not change when in context-sensitive
 187     help mode.
 188
 189     @library{wxcore}
 190     @category{help}
 191
 192     @see wxHelpEvent, wxHelpController, wxContextHelpButton
 193 */
 194 class wxContextHelp : public wxObject
 195 {
 196 public:
 197     /**
 198         Constructs a context help object, calling BeginContextHelp() if
 199         @a doNow is @true (the default).
 200         If @a window is @NULL, the top window is used.
 201     */
 202     wxContextHelp(wxWindow* window = NULL, bool doNow = true);
 203
 204     /**
 205         Destroys the context help object.
 206     */
 207     ~wxContextHelp();
 208
 209     /**
 210         Puts the application into context-sensitive help mode. @a window is the
 211         window which will be used to catch events; if @NULL, the top window
 212         will be used.  Returns @true if the application was successfully put
 213         into context-sensitive help mode.  This function only returns when the
 214         event loop has finished.
 215     */
 216     bool BeginContextHelp(wxWindow* window = NULL);
 217
 218     /**
 219         Ends context-sensitive help mode. Not normally called by the
 220         application.
 221     */
 222     bool EndContextHelp();
 223 };
 224
 225
 226
 227 /**
 228     @class wxContextHelpButton
 229     @wxheader{cshelp.h}
 230
 231     Instances of this class may be used to add a question mark button that when
 232     pressed, puts the application into context-help mode. It does this by
 233     creating a wxContextHelp object which itself generates a wxEVT_HELP event
 234     when the user clicks on a window.
 235
 236     On Windows, you may add a question-mark icon to a dialog by use of the
 237     wxDIALOG_EX_CONTEXTHELP extra style, but on other platforms you will have
 238     to add a button explicitly, usually next to OK, Cancel or similar buttons.
 239
 240     @library{wxcore}
 241     @category{help}
 242
 243     @see wxBitmapButton, wxContextHelp
 244 */
 245 class wxContextHelpButton : public wxBitmapButton
 246 {
 247 public:
 248     /// Default constructor.
 249     wxContextHelpButton();
 250
 251     /**
 252         Constructor, creating and showing a context help button.
 253
 254         @param parent
 255             Parent window. Must not be @NULL.
 256         @param id
 257             Button identifier. Defaults to wxID_CONTEXT_HELP.
 258         @param pos
 259             Button position.
 260         @param size
 261             Button size. If wxDefaultSize is specified then the button is
 262         sized
 263             appropriately for the question mark bitmap.
 264         @param style
 265             Window style.
 266     */
 267     wxContextHelpButton(wxWindow* parent,
 268                         wxWindowID id = wxID_CONTEXT_HELP,
 269                         const wxPoint& pos = wxDefaultPosition,
 270                         const wxSize& size = wxDefaultSize,
 271                         long style = wxBU_AUTODRAW);
 272 };
 273
 274
 275 /**
 276     @class wxSimpleHelpProvider
 277     @wxheader{cshelp.h}
 278
 279     wxSimpleHelpProvider is an implementation of wxHelpProvider which supports
 280     only plain text help strings, and shows the string associated with the
 281     control (if any) in a tooltip.
 282
 283     @library{wxcore}
 284     @category{help}
 285
 286     @see wxHelpProvider, wxHelpControllerHelpProvider, wxContextHelp,
 287          wxWindow::SetHelpText()(, wxWindow::GetHelpTextAtPoint()
 288 */
 289 class wxSimpleHelpProvider : public wxHelpProvider
 290 {
 291 public:
 292
 293 };
 294