| Version: 3.3.1

Public Types | Public Member Functions | List of all members
wxHelpEvent Class Reference
Class List by Category » Events

`#include <wx/event.h>`

Inheritance diagram for wxHelpEvent:
[legend]

## Detailed Description

A help event is sent when the user has requested context-sensitive help.

This can either be caused by the application requesting context-sensitive help mode via wxContextHelp, or (on MS Windows) by the system generating a WM_HELP message when the user pressed F1 or clicked on the query button in a dialog caption.

A help event is sent to the window that the user clicked on, and is propagated up the window hierarchy until the event is processed or there are no more event handlers.

The application should call wxEvent::GetId to check the identity of the clicked-on window, and then either show some suitable help or call wxEvent::Skip() if the identifier is unrecognised.

Calling Skip is important because it allows wxWidgets to generate further events for ancestors of the clicked-on window. Otherwise it would be impossible to show help for container windows, since processing would stop after the first window found.

## Events using this class

The following event handler macros redirect the events to member function handlers 'func' with prototypes like:

void handlerFuncName(wxHelpEvent& event)

Event macros:

- EVT_HELP(id, func):
  Process a `wxEVT_HELP` event.
- EVT_HELP_RANGE(id1, id2, func):
  Process a `wxEVT_HELP` event for a range of ids.

##

Library: wxCore
Category: Events

See also
  wxContextHelp, wxDialog, Events and Event Handling

## Public Types
enum | Origin { Origin_Unknown , Origin_Keyboard , Origin_HelpButton }
| Indicates how a wxHelpEvent was generated. More...

## Public Member Functions
| wxHelpEvent (wxEventType type=wxEVT_NULL, wxWindowID winid=0, const wxPoint &pt=wxDefaultPosition, wxHelpEvent::Origin origin=Origin_Unknown)
| Constructor. More...
wxHelpEvent::Origin | GetOrigin () const
| Returns the origin of the help event which is one of the wxHelpEvent::Origin values. More...
const wxPoint & | GetPosition () const
| Returns the left-click position of the mouse, in screen coordinates. More...
void | SetOrigin (wxHelpEvent::Origin origin)
| Set the help event origin, only used internally by wxWidgets normally. More...
void | SetPosition (const wxPoint &pt)
| Sets the left-click position of the mouse, in screen coordinates. More...
Public Member Functions inherited from wxCommandEvent
| wxCommandEvent (wxEventType commandEventType=wxEVT_NULL, int id=0)
| Constructor. More...
void * | GetClientData () const
| Returns client data pointer for a listbox or choice selection event (not valid for a deselection). More...
wxClientData * | GetClientObject () const
| Returns client object pointer for a listbox or choice selection event (not valid for a deselection). More...
long | GetExtraLong () const
| Returns extra information dependent on the event objects type. More...
int | GetInt () const
| Returns the integer identifier corresponding to a listbox, choice or radiobox selection (only if the event was a selection, not a deselection), or a boolean value representing the value of a checkbox. More...
int | GetSelection () const
| Returns item index for a listbox or choice selection event (not valid for a deselection). More...
wxString | GetString () const
| Returns item string for a listbox or choice selection event. More...
bool | IsChecked () const
| This method can be used with checkbox and menu events: for the checkboxes, the method returns true for a selection event and false for a deselection one. More...
bool | IsSelection () const
| For a listbox or similar event, returns true if it is a selection, false if it is a deselection. More...
void | SetClientData (void *clientData)
| Sets the client data for this event. More...
void | SetClientObject (wxClientData *clientObject)
| Sets the client object for this event. More...
void | SetExtraLong (long extraLong)
| Sets the m_extraLong member. More...
void | SetInt (int intCommand)
| Sets the m_commandInt member. More...
void | SetString (const wxString &string)
| Sets the m_commandString member. More...
Public Member Functions inherited from wxEvent
| wxEvent (int id=0, wxEventType eventType=wxEVT_NULL)
| Constructor. More...
virtual wxEvent * | Clone () const =0
| Returns a copy of the event. More...
wxObject * | GetEventObject () const
| Returns the object (usually a window) associated with the event, if any. More...
wxEventType | GetEventType () const
| Returns the identifier of the given event type, such as `wxEVT_BUTTON`. More...
virtual wxEventCategory | GetEventCategory () const
| Returns a generic category for this event. More...
int | GetId () const
| Returns the identifier associated with this event, such as a button command id. More...
wxObject * | GetEventUserData () const
| Return the user data associated with a dynamically connected event handler. More...
bool | GetSkipped () const
| Returns true if the event handler should be skipped, false otherwise. More...
long | GetTimestamp () const
| Gets the timestamp for the event. More...
bool | IsCommandEvent () const
| Returns true if the event is or is derived from wxCommandEvent else it returns false. More...
void | ResumePropagation (int propagationLevel)
| Sets the propagation level to the given value (for example returned from an earlier call to wxEvent::StopPropagation). More...
void | SetEventObject (wxObject *object)
| Sets the originating object. More...
void | SetEventType (wxEventType type)
| Sets the event type. More...
void | SetId (int id)
| Sets the identifier associated with this event, such as a button command id. More...
void | SetTimestamp (long timeStamp=0)
| Sets the timestamp for the event. More...
bool | ShouldPropagate () const
| Test if this event should be propagated or not, i.e. if the propagation level is currently greater than 0. More...
void | Skip (bool skip=true)
| This method can be used inside an event handler to control whether further event handlers bound to this event will be called after the current one returns. More...
int | StopPropagation ()
| Stop the event from propagating to its parent window. More...
Public Member Functions inherited from wxObject
| wxObject ()
| Default ctor; initializes to nullptr the internal reference data. More...
| wxObject (const wxObject &other)
| Copy ctor. More...
virtual | ~wxObject ()
| Destructor. More...
virtual wxClassInfo * | GetClassInfo () const
| This virtual function is redefined for every class that requires run-time type information, when using the wxDECLARE_CLASS macro (or similar). More...
wxObjectRefData * | GetRefData () const
| Returns the wxObject::m_refData pointer, i.e. the data referenced by this object. More...
bool | IsKindOf (const wxClassInfo *info) const
| Determines whether this class is a subclass of (or the same class as) the given class. More...
bool | IsSameAs (const wxObject &obj) const
| Returns true if this object has the same data pointer as obj. More...
void | Ref (const wxObject &clone)
| Makes this object refer to the data in clone. More...
void | SetRefData (wxObjectRefData *data)
| Sets the wxObject::m_refData pointer. More...
void | UnRef ()
| Decrements the reference count in the associated data, and if it is zero, deletes the data. More...
void | UnShare ()
| This is the same of AllocExclusive() but this method is public. More...
void | operator delete (void *buf)
| The delete operator is defined for debugging versions of the library only, when the identifier `__WXDEBUG__` is defined. More...
void * | operator new (size_t size, const wxString &filename=nullptr, int lineNum=0)
| The new operator is defined for debugging versions of the library only, when the identifier `__WXDEBUG__` is defined. More...

## Additional Inherited Members
Protected Member Functions inherited from wxObject
void | AllocExclusive ()
| Ensure that this object's data is not shared with any other object. More...
virtual wxObjectRefData * | CreateRefData () const
| Creates a new instance of the wxObjectRefData-derived class specific to this object and returns it. More...
virtual wxObjectRefData * | CloneRefData (const wxObjectRefData *data) const
| Creates a new instance of the wxObjectRefData-derived class specific to this object and initializes it copying data. More...
Protected Attributes inherited from wxEvent
int | m_propagationLevel
| Indicates how many levels the event can propagate. More...
Protected Attributes inherited from wxObject
wxObjectRefData * | m_refData
| Pointer to an object which is the object's reference-counted data. More...

## Member Enumeration Documentation

## ◆ Origin

enum wxHelpEvent::Origin

Indicates how a wxHelpEvent was generated.

Enumerator
Origin_Unknown | unrecognized event source.
Origin_Keyboard | event generated from F1 key press.
Origin_HelpButton | event generated by wxContextHelp or from the [?] button on the title bar (Windows).

## Constructor & Destructor Documentation

## ◆ wxHelpEvent()

wxHelpEvent::wxHelpEvent | ( | wxEventType | type = `wxEVT_NULL`,
|  | wxWindowID | winid = `0`,
|  | const wxPoint & | pt = `wxDefaultPosition`,
|  | wxHelpEvent::Origin | origin = `Origin_Unknown`
| ) |  |

Constructor.

## Member Function Documentation

## ◆ GetOrigin()

wxHelpEvent::Origin wxHelpEvent::GetOrigin | ( |  | ) | const

Returns the origin of the help event which is one of the wxHelpEvent::Origin values.

The application may handle events generated using the keyboard or mouse differently, e.g. by using wxGetMousePosition() for the mouse events.

See also
  SetOrigin()

## ◆ GetPosition()

const wxPoint& wxHelpEvent::GetPosition | ( |  | ) | const

Returns the left-click position of the mouse, in screen coordinates.

This allows the application to position the help appropriately.

## ◆ SetOrigin()

void wxHelpEvent::SetOrigin | ( | wxHelpEvent::Origin | origin | ) |

Set the help event origin, only used internally by wxWidgets normally.

See also
  GetOrigin()

## ◆ SetPosition()

void wxHelpEvent::SetPosition | ( | const wxPoint & | pt | ) |

Sets the left-click position of the mouse, in screen coordinates.