:orphan:

.. _temperature.py:

temperature.py
==============

.. code-block:: py
    :linenos:


    """
    This example demonstrates how props can set each-other without
    getting into an infinite loop.
    """
    
    from flexx import event
    
    
    class Temperature(event.HasEvents):
        """ Temperature object with a settable prop for both Celcius and
        Fahrenheit.
        """
        
        @event.prop
        def C(self, t=0):
            t = float(t)
            self.F = t * 1.8 + 32
            return t
        
        @event.prop
        def F(self, t=0):
            t = float(t)
            self.C = (t - 32) / 1.8
            return t
        
        @event.connect('C', 'F')
        def on_temp_change(self, *events):
            # This gets called once with two events when either C or F is changed.
            print('  temp in Celcius: %1.1f C' % self.C)
            print('  temp in Fahrenheit: %1.1f F' % self.F)
    
    t = Temperature()
    
    print('Water if freezing:')
    t.C = 0
    
    print('Average annual temp in California')
    t.F = 59.4
    
    event.loop.iter()