MainWindow
 
  
   
    69
    0
    800
    600
   
  
  
   MainWindow
  
  
   
    
     
      40
      30
      99
      27
     
    
    
     PushButton
    
   
   
    
     
      160
      160
      99
      27
     
    
    
     PushButton
    
   
   
    
     
      370
      310
      99
      27
     
    
    
     PushButton
    
   
  
  
   
    
     0
     0
     800
     25