 
 subsubsection3_8_4_5.html  subsection3_8_4.html  subsubsectionstar3_8_4_3.html  tableofcontents3_1.html   Next: subsubsection3_8_4_5.html The SetBindings Method Up: subsection3_8_4.html Standard Initialization Methods  Previous: subsubsectionstar3_8_4_3.html  The tixChainMethod call    The ConstructWidget Method  
The 
ConstructWidget method is used to creates the components
  of a widget instance. In the case of TixArrowButton, we want to
  create a new button subwidget, whose name is 
button, and use a
  bitmap to display an arrow on this button. Assuming the bitmap files
  are stored in the files 
up.xbm, down.xbm, left.xbm  and 
right.xbm, the string substitution @$data(-direction).xbm will give us the appropriate bitmap
  depending on the current direction option of the widget instance.
  proc tixArrowButton:ConstructWidget {w} {    upvar #0 $w data
    tixChainMethod $w ConstructWidget
    set data(w:button) [button $w.button -bitmap @$data(-direction).xbm]
    pack $data(w:button) -expand yes -fill both
}
The tixArrowButton:ConstructWidget method shown above sets
  the variable 
data(w:button) to be the pathname of the button subwidget. As a convention of the Tix Intrinsics, we must
  declare a public subwidget 
swid by storing its pathname in the
  variable 
data(w:swid).
http://tix.sourceforge.nethttp://tix.sourceforge.net 