diff options
Diffstat (limited to 'documentation')
| -rw-r--r-- | documentation/src/events.dox | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/documentation/src/events.dox b/documentation/src/events.dox index 2dc1c7b25..68f978126 100644 --- a/documentation/src/events.dox +++ b/documentation/src/events.dox @@ -190,6 +190,42 @@ You can also make "global" shortcuts by using Fl::add_handler(). A global shortcut will work no matter what windows are displayed or which one has the focus. +Since version 1.4, FLTK has 3 default global shortcuts (\c Ctrl/+/-/0/ +or \c Cmd/+/-/0/ under macOS) that change the value of the GUI scaling +factor. \c Ctrl+ zooms-in all app windows of the focussed display +(all displays under macOS); +\c Ctrl- zooms-out these windows; \c Ctrl 0 restores the initial value of the +scaling factor. Although characters '+' and '0' are located in +the shifted position of their keyboard key in some +keyboard layouts, these shortcuts are to be used without pressing +the shift key, for user convenience. In other words, press only +\c Ctrl (or \c Cmd) and the key labelled '+' or '0' independently of +whether '+' or '0' is in shifted or unshifted position on the keyboard. + +These scaling shortcuts are installed when the FLTK +library opens the display. They have a lower priority than any shortcut +defined in any menu and than any user-provided event handler +(see Fl::add_handler()) installed after FLTK opened the display. +Therefore, if a menu item of an FLTK app is given FL_COMMAND+'+' +as shortcut, that item's callback rather than FLTK's default zooming-in +routine is triggered when \c Ctrl+ (or \c Cmd+) is pressed . +If any window of the display is fullscreen or maximized, +scaling shortcuts have no effect. + +It's possible to deactivate FLTK's default scaling shortcuts adding +this global event handler +\code +int no_zoom_handler(int event) { + if (event != FL_SHORTCUT) return 0; + if (Fl::test_shortcut(FL_COMMAND+'+')) return 1; + if (Fl::test_shortcut(FL_COMMAND+'-')) return 1; + if (Fl::test_shortcut(FL_COMMAND+'0')) return 1; + return 0; +} +\endcode +with statement \c Fl::add_handler(no_zoom_handler); after FLTK has opened the +display. + \section events_widget Widget Events \subsection events_fl_deactivate FL_DEACTIVATE |