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Tk_Grab(3tk) Tk Library Procedures Tk_Grab(3tk) 





NAME


Tk_Grab, Tk_Ungrab - manipulate grab state in an application






SYNOPSIS


#include <tk.h>

int
Tk_Grab(interp, tkwin, grabGlobal)

void
Tk_Ungrab(tkwin)






ARGUMENTS



  
Tcl_Interp *interp (in)

  
Interpreter to use for error reporting

  
Tk_Window tkwin (in)

  
Window on whose behalf the pointer is to be grabbed or released

  
int grabGlobal (in)

  
Boolean indicating whether the grab is global or application local
    
    

    

  








DESCRIPTION


These functions are used to set or release a global or application
    local grab. When a grab is set on a particular window in a Tk application,
    mouse and keyboard events can only be received by that window and its
    descendants. Mouse and keyboard events for windows outside the tree rooted
    at tkwin will be redirected to tkwin. If the grab is global,
    then all mouse and keyboard events for windows outside the tree rooted at
    tkwin (even those intended for windows in other applications) will be
    redirected to tkwin. If the grab is application local, only mouse and
    keyboard events intended for a windows within the same application (but
    outside the tree rooted at tkwin) will be redirected.


Tk_Grab sets a grab on a particular window. Tkwin
    specifies the window on whose behalf the pointer is to be grabbed.
    GrabGlobal indicates whether the grab should be global or application
    local; if it is non-zero, it means the grab should be global. Normally,
    Tk_Grab returns TCL_OK; if an error occurs and the grab cannot
    be set, TCL_ERROR is returned and an error message is left if
    interp's result. Once this call completes successfully, no window
    outside the tree rooted at tkwin will receive pointer- or
    keyboard-related events until the next call to Tk_Ungrab. If a previous grab
    was in effect within the application, then it is replaced with a new
  one.


Tk_Ungrab releases a grab on the mouse pointer and
    keyboard, if there is one set on the window given by tkwin. Once a
    grab is released, pointer and keyboard events will start being delivered to
    other windows again.






KEYWORDS


grab, window







  

    
    Tk