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1. Introduction

This chapter describes the way in which LessTif widgets handle their geometry negotiations. As geometry management is a subject that has much to do with the Xt Intrinsics, part of this document describes (what we understand of) the Xt geometry model.

The Xt geometry model is based on geometry negotiations: every change that a widget wants to apply to its own geometry must first be approved by the widget's parent. The resources of the widget that are part of this geometry negotiation mechanism are:


\begin{itemlist}
\item the position coordinates \code{x} and \code{y},
\item the...
...width} and \code{height},
\item and finally \code{border\_width}.
\end{itemlist}

XtMakeGeometryRequestXtMakeResizeRequest_XmMakeGeometryRequestA widget can request a geometry change by using XtMakeGeometryRequest() or XtMakeResizeRequest(). Whereas XtMakeGeometryRequest() can be used to change all five geometry resources mentioned above, XtMakeResizeRequest() only allows a widget to request a different size (width and/or height) and is in the end just a convenience function for such cases where the position of your widget doesn't matter.

In addition, LESSTIF has a convenience function called _XmMakeGeometryRequest() which calls XtMakeGeometryRequest(). But more on it below.


next up previous contents index
Next: 2. Making Geometry Requests Up: 5. Messy Geometry Management Previous: 5. Messy Geometry Management   Contents   Index
Danny Backx
2000-12-13