wxPython/wx/lib/anchors.py

   1 #----------------------------------------------------------------------
   2 # Name:        wxPython.lib.anchors
   3 # Purpose:     A class that provides an easy to use interface over layout
   4 #              constraints for anchored layout.
   5 #
   6 # Author:      Riaan Booysen
   7 #
   8 # Created:     15-Dec-2000
   9 # RCS-ID:      $Id$
  10 # Copyright:   (c) 2000 by Total Control Software
  11 # Licence:     wxWindows license
  12 #----------------------------------------------------------------------
  13 # 11/30/2003 - Jeff Grimmett (grimmtooth@softhome.net)
  14 #
  15 # o Updated for wx namespace
  16 # o Tested with updated demo
  17 #
  18
  19 import  wx
  20
  21 class LayoutAnchors(wx.LayoutConstraints):
  22     """ A class that implements Delphi's Anchors with wx.LayoutConstraints.
  23
  24         Anchored sides maintain the distance from the edge of the
  25         control to the same edge of the parent.
  26         When neither side is selected, the control keeps the same
  27         relative position to both sides.
  28
  29         The current position and size of the control and it's parent
  30         is used when setting up the constraints. To change the size or
  31         position of an already anchored control, set the constraints to
  32         None, reposition or resize and reapply the anchors.
  33
  34         Examples:
  35
  36         Let's anchor the right and bottom edge of a control and
  37         resize it's parent.
  38
  39         ctrl.SetConstraints(LayoutAnchors(ctrl, left=0, top=0, right=1, bottom=1))
  40
  41         +=========+         +===================+
  42         | +-----+ |         |                   |
  43         | |     * |   ->    |                   |
  44         | +--*--+ |         |           +-----+ |
  45         +---------+         |           |     * |
  46                             |           +--*--+ |
  47                             +-------------------+
  48         * = anchored edge
  49
  50         When anchored on both sides the control will stretch horizontally.
  51
  52         ctrl.SetConstraints(LayoutAnchors(ctrl, 1, 0, 1, 1))
  53
  54         +=========+         +===================+
  55         | +-----+ |         |                   |
  56         | *     * |   ->    |                   |
  57         | +--*--+ |         | +---------------+ |
  58         +---------+         | *     ctrl      * |
  59                             | +-------*-------+ |
  60                             +-------------------+
  61         * = anchored edge
  62     """
  63     def __init__(self, control, left=1, top=1, right=0, bottom=0):
  64         wx.LayoutConstraints.__init__(self)
  65         parent = control.GetParent()
  66         if not parent: return
  67
  68         pPos, pSize = parent.GetPosition(), parent.GetClientSize()
  69         cPos, cSize = control.GetPosition(), control.GetSize()
  70
  71         self.setConstraintSides(self.left, wx.Left, left,
  72                                 self.right, wx.Right, right,
  73                                 self.width, wx.Width, self.centreX,
  74                                 cPos.x, cSize.width, pSize.width, parent)
  75
  76         self.setConstraintSides(self.top, wx.Top, top,
  77                                 self.bottom, wx.Bottom, bottom,
  78                                 self.height, wx.Height, self.centreY,
  79                                 cPos.y, cSize.height, pSize.height, parent)
  80
  81     def setConstraintSides(self, side1, side1Edge, side1Anchor,
  82                                  side2, side2Edge, side2Anchor,
  83                                  size, sizeEdge, centre,
  84                                  cPos, cSize, pSize, parent):
  85         if side2Anchor:
  86             side2.SameAs(parent, side2Edge, pSize - (cPos + cSize))
  87
  88         if side1Anchor:
  89             side1.SameAs(parent, side1Edge, cPos)
  90
  91             if not side2Anchor:
  92                 size.AsIs()
  93         else:
  94             size.AsIs()
  95
  96             if not side2Anchor:
  97                 centre.PercentOf(parent, sizeEdge,
  98                                  int(((cPos + cSize / 2.0) / pSize)*100))
  99