Tk_CreateBindingTable(3)				       Tk Library Procedures					  Tk_CreateBindingTable(3)

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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)

       const 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_CreateBind-
						  ingTable.

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

       const 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.
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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  asso-
       ciated  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  asso-
       ciated,	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 XSe-
       lectInput 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 con-
       tinue as described in the documentation for bind.

KEYWORDS

       binding, event, object, script

Tk									4.0						  Tk_CreateBindingTable(3)