Ubuntu Manpage: XkbChangeIndicators - Changes indicator maps or state without passing the entire keyboard

Provided by: libx11-doc_1.6.3-1ubuntu2.2_all

NAME

       XkbChangeIndicators  - Changes indicator maps or state without passing the entire keyboard
       description

SYNOPSIS

       Bool XkbChangeIndicators (Display *dpy, XkbDescPtr  xkb,  XkbIndicatorChangesPtr  changes,
              unsigned int state);

ARGUMENTS

       - dpy  connection to the X server

       - xkb  keyboard description from which names are to be taken.

       - changes
              indicators to be updated on the server

       - state
              new state of indicators listed in changes->state_changes

DESCRIPTION

The XkbIndicatorChangesRec identifies small modifications to the indicator map. Use it
with the function XkbChangeIndicators to reduce the amount of traffic sent to the server
(see STRUCTURES).

The state_changes field is a mask that specifies the indicators that have changed state,
and map_changes is a mask that specifies the indicators whose maps have changed.

XkbChangeIndicators copies any maps specified by changes from the keyboard description,
xkb, to the server specified by dpy. If any bits are set in the state_changes field of
changes, XkbChangeIndicators also sets the state of those indicators to the values
specified in the state mask. A 1 bit in state turns the corresponding indicator on, a 0
bit turns it off.

In addition, it can also generate XkbIndicatorStateNotify and XkbIndicatorMapNotify
events.

Whenever an indicator changes state, the server sends XkbIndicatorStateNotify events to
all interested clients. Similarly, whenever an indicator's map changes, the server sends
XkbIndicatorMapNotify events to all interested clients.

To receive XkbIndicatorStateNotify events, use XkbSelectEvents with both the
bits_to_change and values_for_bits parameters containing XkbIndicatorStateNotifyMask. To
receive XkbIndicatorMapNotify events, use XkbSelectEvents with XkbIndicatorMapNotifyMask.

To receive events for only specific indicators, use XkbSelectEventDetails. Set the
event_type parameter to XkbIndicatorStateNotify or XkbIndicatorMapNotify, and set both the
bits_to_change and values_for_bits detail parameters to a mask where each bit specifies
one indicator, turning on those bits that specify the indicators for which you want to
receive events.

xkb_type is either XkbIndicatorStateNotify or XkbIndicatorMapNotify, depending on whether
the event is a kbIndicatorStateNotify event or kbIndicatorMapNotify event.

The changed parameter is a mask that is the bitwise inclusive OR of the indicators that
have changed. If the event is of type XkbIndicatorMapNotify, changed reports the maps that
changed. If the event is of type XkbIndicatorStateNotify, changed reports the indicators
that have changed state. state is a mask that specifies the current state of all
indicators, whether they have changed or not, for both XkbIndicatorStateNotify and
IndicatorMapNotify events.

STRUCTURES

            typedef struct _XkbIndicatorChanges {
                unsigned int          state_changes;
                unsigned int           map_changes;
            }XkbIndicatorChangesRec,*XkbIndicatorChangesPtr;

       Both types of indicator events use the same structure:

           typedef struct _XkbIndicatorNotify {
               int            type;        /∗ Xkb extension base event code */
               unsigned long  serial;      /∗ X server serial number for event */
               Bool           send_event;  /∗ True => synthetically generated */
               Display *      display;     /∗ server connection where event generated */
               Time           time;        /∗ server time when event generated */
               int            xkb_type;    /∗ specifies state or map notify */
               int            device;      /∗ Xkb device ID, will not be XkbUseCoreKbd*/
               unsigned int   changed;     /∗ mask of indicators with new state or map */
               unsigned int   state;       /∗ current state of all indicators */
           } XkbIndicatorNotifyEvent;

DIAGNOSTICS