PyGTK - Layout Class


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The gtk.Layout is a container widget similar to gtk.Fixed. Widgets are placed in Layout widget by specifying absolute coordinates. However, the Layout differs from fixed widget in the following ways −

  • The layout widget can have infinite width and height. The maximum value of width and height is limited by the size of unsigned integer.

  • A gtk.DrawingArea widget can be enclosed in a layout container. The DrawingArea is a canvas on which 2D elements like line, rectangle etc. can be drawn.

  • In order to put the Layout container in the toplevel window of lesser dimensions, it can be associated with the scrollbars or can be placed in a ScrolledWindow.

The gtk.Layout class has the following constructor −

gtk.Layout(hadjustment = None, vadjustment = None)

The hadjustment and vadjustment properties represent an object having an adjustable bounded value.

The following table lists out the frequently used methods of the layout −

put(widget, x, y) Places a child widget at the specified coordinates
set_size(w, h) Sets the size of the Layout container to the specified width and height

The Layout object emits the set_scroll_adjustment signal when the adjustments associated with it are changed.

Example

In the following example, a Label is paced at the centre of a Layout container, which in turn is to be placed in a toplevel window of smaller size. Hence, it is first added to a ScrolledWindow and the ScrolledWindow is then added to the main window.

Observe the code −

import gtk

class PyApp(gtk.Window):
   
   def __init__(self):
      super(PyApp, self).__init__()
      self.set_title("layout")
      self.set_size_request(300,200)
      self.set_position(gtk.WIN_POS_CENTER)
      sc = gtk.ScrolledWindow()
      lo = gtk.Layout()
      lo.set_size(400,400)
      button = gtk.Button("Press Me")
      lo.put(button, 125,200)
      sc.add(lo)
      self.add(sc)
      self.connect("destroy", gtk.main_quit)
      self.show_all()

PyApp()
gtk.main()

The above code will generate the following output −

Layout

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