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wx.PySizer
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Inheritance diagram for `wx.PySizer`:

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.. inheritance-diagram:: wx.PySizer

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Description
===========

`wx.PySizer` is a special version of `wx.Sizer <wx.Sizer.html>`_ that has been instrumented to allow the C++ virtual methods to be overloaded in Python derived classes. 
You would derive from this class if you are wanting to implement a custom sizer in Python code. Simply implement `CalcMin <wx.Sizer.html#CalcMin>`_ and 
`RecalcSizes <wx.Sizer.html#RecalcSizes>`_ in the derived class and you're all set. 

For example:: 

    class MySizer(wx.PySizer):  
        """ A simple wx.PySizer derived class. """

        def __init__(self):   
            """ Default class constructor. """

            wx.PySizer.__init__(self)  

 
        def CalcMin(self):   
            "Re-implemented from wx.Sizer.CalcMin. """

            for item in self.GetChildren():    
                # Calculate the total minimum width and height needed    
                # by all items in the sizer according to this sizer's    
                # layout algorithm.    

                DoSizeCalculation(item)

            return wx.Size(width, height)   


        def RecalcSizes(self):   
            "Re-implemented from wx.Sizer.RecalcSizes. """

            # Find the space allotted to this sizer   
            pos = self.GetPosition()   
            size = self.GetSize()   

            for item in self.GetChildren():    
                # Recalculate (if necessary) the position and size of    
                # each item and then call item.SetDimension to do the    
                # actual positioning and sizing of the items within the    
                # space alloted to this sizer.    

                item.SetDimension(itemPos, itemSize) 


When `Layout <wx.Sizer.html#Layout>`_ is called it first calls `CalcMin <wx.Sizer.html#CalcMin>`_ followed by `RecalcSizes <wx.Sizer.html#RecalcSizes>`_ so you can 
optimize a bit by saving the results of `CalcMin <wx.Sizer.html#CalcMin>`_ and reusing them in `RecalcSizes <wx.Sizer.html#RecalcSizes>`_. 

.. seealso:: `wx.SizerItem <wx.SizerItem.html>`_, `wx.Sizer.GetChildren <wx.Sizer.html#GetChildren>`_


Derived From
^^^^^^^^^^^^^

* `wx.Sizer <wx.Sizer.html>`_ 
* `wx.Object <wx.Object.html>`_ 


Methods Summary
^^^^^^^^^^^^^^^

* `__init__ <#__init__>`_ 


Class API
=========

Methods
^^^^^^^


.. method:: __init__()

   Creates a `wx.PySizer`. Must be called from the `__init__` in the derived class.

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   **Returns:**

   `wx.PySizer <wx.PySizer.html>`_