bindtable(3Tk)

Tk_CreateBindingTable, Tk_DeleteBindingTable, Tk_CreateBinding, Tk_DeleteBinding, Tk_GetBinding, Tk_GetAllBindings, Tk_DeleteAllBindings, Tk_BindEvent - invoke scripts in response to X events

As shipped in IRIX 6.5.30. Unchanged since IRIX 6.5.

NAME
     Tk_CreateBindingTable, Tk_DeleteBindingTable, Tk_CreateBinding,
     Tk_DeleteBinding, Tk_GetBinding, Tk_GetAllBindings, Tk_DeleteAllBindings,
     Tk_BindEvent - invoke scripts in response to X events

SYNOPSIS
     #include <tk.h>

     Tk_BindingTable
     Tk_CreateBindingTable(interp)

     Tk_DeleteBindingTable(bindingTable)

     unsigned long
     Tk_CreateBinding(interp, bindingTable, object, eventString, script, append)

     int
     Tk_DeleteBinding(interp, bindingTable, object, eventString)

     char *
     Tk_GetBinding(interp, bindingTable, object, eventString)

     Tk_GetAllBindings(interp, bindingTable, object)

     Tk_DeleteAllBindings(bindingTable, object)

     Tk_BindEvent(bindingTable, eventPtr, tkwin, numObjects, objectPtr)

ARGUMENTS
     Tcl_Interp        *interp        (in)      Interpreter to use when
                                                invoking bindings in binding
                                                table.  Also used for
                                                returning results and errors
                                                from binding procedures.

     Tk_BindingTable   bindingTable   (in)      Token for binding table;  must
                                                have been returned by some
                                                previous call to
                                                Tk_CreateBindingTable.

     ClientData        object         (in)      Identifies object with which
                                                binding is associated.

     char              *eventString   (in)      String describing event
                                                sequence.

     char              *script        (in)      Tcl script to invoke when
                                                binding triggers.

     int               append         (in)      Non-zero means append script
                                                to existing script for
                                                binding, if any; zero means
                                                replace existing script with
                                                new one.

     XEvent            *eventPtr      (in)      X event to match against
                                                bindings in bindingTable.

     Tk_Window         tkwin          (in)      Identifier for any window on
                                                the display where the event
                                                occurred.  Used to find
                                                display-related information
                                                such as key maps.

     int               numObjects     (in)      Number of object identifiers
                                                pointed to by objectPtr.

     ClientData        *objectPtr     (in)      Points to an array of object
                                                identifiers:  bindings will be
                                                considered for each of these
                                                objects in order from first to
                                                last.


DESCRIPTION
     These procedures provide a general-purpose mechanism for creating and
     invoking bindings.  Bindings are organized in terms of binding tables.  A
     binding table consists of a collection of bindings plus a history of
     recent events.  Within a binding table, bindings are associated with
     objects.  The meaning of an object is defined by clients of the binding
     package.  For example, Tk keeps uses one binding table to hold all of the
     bindings created by the bind command.  For this table, objects are
     pointers to strings such as window names, class names, or other binding
     tags such as all.  Tk also keeps a separate binding table for each canvas
     widget, which manages bindings created by the canvas's bind widget
     command;  within this table, an object is either a pointer to the
     internal structure for a canvas item or a Tk_Uid identifying a tag.

     The procedure Tk_CreateBindingTable creates a new binding table and
     associates interp with it (when bindings in the table are invoked, the
     scripts will be evaluated in interp).  Tk_CreateBindingTable returns a
     token for the table, which must be used in calls to other procedures such
     as Tk_CreateBinding or Tk_BindEvent.

     Tk_DeleteBindingTable frees all of the state associated with a binding
     table.  Once it returns the caller should not use the bindingTable token
     again.

     Tk_CreateBinding adds a new binding to an existing table.  The object
     argument identifies the object with which the binding is to be
     associated, and it may be any one-word value.  Typically it is a pointer
     to a string or data structure.  The eventString argument identifies the
     event or sequence of events for the binding;  see the documentation for
     the bind command for a description of its format.  script is the Tcl
     script to be evaluated when the binding triggers.  append indicates what
     to do if there already exists a binding for object and eventString:  if
     append is zero then script replaces the old script;  if append is non-
     zero then the new script is appended to the old one.  Tk_CreateBinding
     returns an X event mask for all the events associated with the bindings.
     This information may be useful to invoke XSelectInput to select relevant
     events, or to disallow the use of certain events in bindings.  If an
     error occurred while creating the binding (e.g., eventString refers to a
     non-existent event), then 0 is returned and an error message is left in
     interp->result.

     Tk_DeleteBinding removes from bindingTable the binding given by object
     and eventString, if such a binding exists.  Tk_DeleteBinding always
     returns TCL_OK.  In some cases it may reset interp->result to the default
     empty value.

     Tk_GetBinding returns a pointer to the script associated with eventString
     and object in bindingTable.  If no such binding exists then NULL is
     returned and an error message is left in interp->result.

     Tk_GetAllBindings returns in interp->result a list of all the event
     strings for which there are bindings in bindingTable associated with
     object.  If there are no bindings for object then an empty string is
     returned in interp->result.

     Tk_DeleteAllBindings deletes all of the bindings in bindingTable that are
     associated with object.

     Tk_BindEvent is called to process an event.  It makes a copy of the event
     in an internal history list associated with the binding table, then it
     checks for bindings that match the event.  Tk_BindEvent processes each of
     the objects pointed to by objectPtr in turn.  For each object, it finds
     all the bindings that match the current event history, selects the most
     specific binding using the priority mechanism described in the
     documentation for bind, and invokes the script for that binding.  If
     there are no matching bindings for a particular object, then the object
     is skipped.  Tk_BindEvent continues through all of the objects, handling
     exceptions such as errors, break, and continue as described in the
     documentation for bind.


KEYWORDS
     binding, event, object, script