/**
@class wxKeyEvent
- This event class contains information about keypress (character) events.
+ This event class contains information about key press and release events.
Notice that there are three different kinds of keyboard events in wxWidgets:
key down and up events and char events. The difference between the first two
generated) down events but only one up so it is wrong to assume that there is
one up event corresponding to each down one.
- Both key events provide untranslated key codes while the char event carries
- the translated one. The untranslated code for alphanumeric keys is always
- an upper case value. For the other keys it is one of @c WXK_XXX values
- from the ::wxKeyCode enumeration.
- The translated key is, in general, the character the user expects to appear
- as the result of the key combination when typing the text into a text entry
- zone, for example.
+ Both key down and up events provide untranslated key codes while the char
+ event carries the translated one. The untranslated code for alphanumeric
+ keys is always an upper case value. For the other keys it is one of @c
+ WXK_XXX values from the ::wxKeyCode enumeration. The translated key is, in
+ general, the character the user expects to appear as the result of the key
+ combination when typing the text into a text entry zone, for example.
A few examples to clarify this (all assume that CAPS LOCK is unpressed
and the standard US keyboard): when the @c 'A' key is pressed, the key down
Although in this simple case it is clear that the correct key code could be
found in the key down event handler by checking the value returned by
- wxKeyEvent::ShiftDown(), in general you should use @c EVT_CHAR for this as
- for non-alphanumeric keys the translation is keyboard-layout dependent and
- can only be done properly by the system itself.
+ wxKeyEvent::ShiftDown(), in general you should use @c EVT_CHAR if you need
+ the translated key as for non-alphanumeric keys the translation is
+ keyboard-layout dependent and can only be done properly by the system
+ itself.
Another kind of translation is done when the control key is pressed: for
example, for CTRL-A key press the key down event still carries the
same key code @c 'a' as usual but the char event will have key code of 1,
the ASCII value of this key combination.
+ Notice that while pressing any key will generate a key down event (except
+ in presence of IME perhaps) a few special keys don't generate a char event:
+ currently, Shift, Control (or Command), Alt (or Menu or Meta) and Caps, Num
+ and Scroll Lock keys don't do it. For all the other keys you have the
+ choice about whether to choose key down or char event for handling it and
+ either can be used. However it is advised to use char events only for the
+ keys that are supposed to generate characters on screen and key down events
+ for all the rest.
+
+
You may discover how the other keys on your system behave interactively by
- running the @ref page_samples_text wxWidgets sample and pressing some keys
- in any of the text controls shown in it.
+ running the @ref page_samples_keyboard wxWidgets sample and pressing some
+ keys in it.
@b Tip: be sure to call @c event.Skip() for events that you don't process in
key event function, otherwise menu shortcuts may cease to work under Windows.
@note For Windows programmers: The key and char events in wxWidgets are
similar to but slightly different from Windows @c WM_KEYDOWN and
@c WM_CHAR events. In particular, Alt-x combination will generate a
- char event in wxWidgets (unless it is used as an accelerator).
+ char event in wxWidgets (unless it is used as an accelerator) and
+ almost all keys, including ones without ASCII equivalents, generate
+ char events too.
@beginEventTable{wxKeyEvent}
/**
Returns the virtual key code. ASCII events return normal ASCII values,
- while non-ASCII events return values such as @b WXK_LEFT for the left cursor
- key. See ::wxKeyCode for a full list of the virtual key codes.
+ while non-ASCII events return values such as @b WXK_LEFT for the left
+ cursor key. See ::wxKeyCode for a full list of the virtual key codes.
- Note that in Unicode build, the returned value is meaningful only if the
- user entered a character that can be represented in current locale's default
- charset. You can obtain the corresponding Unicode character using GetUnicodeKey().
+ Note that in Unicode build, the returned value is meaningful only if
+ the user entered a character that can be represented in current
+ locale's default charset. You can obtain the corresponding Unicode
+ character using GetUnicodeKey().
*/
int GetKeyCode() const;
/**
Returns the Unicode character corresponding to this key event.
+ If the key pressed doesn't have any character value (e.g. a cursor key)
+ this method will return 0.
+
This function is only available in Unicode build, i.e. when
@c wxUSE_UNICODE is 1.
*/
@class wxShowEvent
An event being sent when the window is shown or hidden.
+ The event is triggered by calls to wxWindow::Show(), and any user
+ action showing a previously hidden window or vice versa (if allowed by
+ the current platform and/or window manager).
+ Notice that the event is not triggered when the application is iconized
+ (minimized) or restored under wxMSW.
Currently only wxMSW, wxGTK and wxOS2 generate such events.
projects / wxWidgets.git / blobdiff