+class LayoutAnchors(wx.LayoutConstraints):
+ """ A class that implements Delphi's Anchors with wx.LayoutConstraints.
+
+ Anchored sides maintain the distance from the edge of the
+ control to the same edge of the parent.
+ When neither side is selected, the control keeps the same
+ relative position to both sides.
+
+ The current position and size of the control and it's parent
+ is used when setting up the constraints. To change the size or
+ position of an already anchored control, set the constraints to
+ None, reposition or resize and reapply the anchors.
+
+ Examples:
+
+ Let's anchor the right and bottom edge of a control and
+ resize it's parent.
+
+ ctrl.SetConstraints(LayoutAnchors(ctrl, left=0, top=0, right=1, bottom=1))
+
+ +=========+ +===================+
+ | +-----+ | | |
+ | | * | -> | |
+ | +--*--+ | | +-----+ |
+ +---------+ | | * |
+ | +--*--+ |
+ +-------------------+
+ * = anchored edge
+
+ When anchored on both sides the control will stretch horizontally.
+
+ ctrl.SetConstraints(LayoutAnchors(ctrl, 1, 0, 1, 1))
+
+ +=========+ +===================+
+ | +-----+ | | |
+ | * * | -> | |
+ | +--*--+ | | +---------------+ |
+ +---------+ | * ctrl * |
+ | +-------*-------+ |
+ +-------------------+
+ * = anchored edge
+ """
+ def __init__(self, control, left=1, top=1, right=0, bottom=0):
+ wx.LayoutConstraints.__init__(self)
+ parent = control.GetParent()
+ if not parent: return
+
+ pPos, pSize = parent.GetPosition(), parent.GetClientSize()
+ cPos, cSize = control.GetPosition(), control.GetSize()
+
+ self.setConstraintSides(self.left, wx.Left, left,
+ self.right, wx.Right, right,
+ self.width, wx.Width, self.centreX,
+ cPos.x, cSize.width, pSize.width, parent)
+
+ self.setConstraintSides(self.top, wx.Top, top,
+ self.bottom, wx.Bottom, bottom,
+ self.height, wx.Height, self.centreY,
+ cPos.y, cSize.height, pSize.height, parent)
+
+ def setConstraintSides(self, side1, side1Edge, side1Anchor,
+ side2, side2Edge, side2Anchor,
+ size, sizeEdge, centre,
+ cPos, cSize, pSize, parent):
+ if side2Anchor:
+ side2.SameAs(parent, side2Edge, pSize - (cPos + cSize))
+
+ if side1Anchor:
+ side1.SameAs(parent, side1Edge, cPos)
+
+ if not side2Anchor:
+ size.AsIs()
+ else:
+ size.AsIs()
+
+ if not side2Anchor:
+ centre.PercentOf(parent, sizeEdge,
+ int(((cPos + cSize / 2.0) / pSize)*100))