title: How to make it from top ? (Cocoa sheet)
body: <p>I have implemented my sheet (NSPanel) with the following method: </p>
  
  <pre><code>- (void)showInWindow:(NSWindow *)mainWindow {
  if (!finestra1)
      [NSBundle loadNibNamed:@"XibName" owner:self];
  
  [NSApp beginSheet:finestra1 modalForWindow:mainWindow modalDelegate:nil didEndSelector:nil contextInfo:nil];
  [NSApp runModalForWindow:finestra1];   //This call blocks the execution until [NSApp stopModal] is called
  </code></pre>
  
  <p>}</p>
  
  <p>The sheet is appearing in the middle of my screen, how to attach it to the top of my main window and make it appear with a "slide down" effect instead?</p>
  
  <p>Thanks in advance.</p>