title: SetHidden not working
body: <p>I am developing an application in cocoa.I need to hide a progress bar placed in an NSView 
  and show an NSTextfield in that place .I used the following cod
  [progressbar setHidden:TRUE]
  [textfield setHidden:FALSE];
  But this code snippet is not working. Is that a bug.??I used to hide the same code to hide certain other text fields in the same page .But that controls became hidden.looking for a solution...</p>