title: menubutton usage in TCL/TK to create dropdown menu in same window
body: <p>I am trying to create a drop-down menu in TCL/TK . I came across some examples and tried , the code is shown below </p>
  
  <pre><code>. configure  -width  400 -height 400 
  label .header -text "Bitfields"
  place .header -x 5 -y 0
  entry .name -textvar username 
  label .username -text "F_name"
  place .name -x 60 -y 20
  place .username -x 2 -y 20
  
  toplevel .win
  menu .win.menubar
  .win configure -menu .win.menubar
  
  set m .win.menubar
  menu $m.w_axs
  $m add cascade -menu $m.w_axs -label W_AXS
  $m.w_axs add command -label "write" -command "write"
  $m.w_axs add command -label "read" -command "write"
  </code></pre>
  
  <p>This is creating a separate window , but I need it in the same window with the other entries. Tried googling for answers but couldn't find any.</p>