Tk_MaintainGeometry


HOME

Tk_MaintainGeometry

NAME
SYNOPSIS
ARGUMENTS
DESCRIPTION
KEYWORDS

___________________________

NAME

Tk_MaintainGeometry, Tk_UnmaintainGeometry − maintain geometry of one window relative to another

SYNOPSIS

#include <tk.h>

Tk_MaintainGeometry(slave, master, x, y, width, height)

Tk_UnmaintainGeometry(slave, master)

ARGUMENTS

Tk_Window slave (in)

Window whose geometry is to be controlled.

Tk_Window master (in)

Window relative to which slave’s geometry will be controlled.

int x (in)

Desired x-coordinate of slave in master, measured in pixels from the inside of master’s left border to the outside of slave’s left border.

int y (in)

Desired y-coordinate of slave in master, measured in pixels from the inside of master’s top border to the outside of slave’s top border.

int width (in)

Desired width for slave, in pixels.

int height (in)

Desired height for slave, in pixels.

______________

DESCRIPTION

Tk_MaintainGeometry and Tk_UnmaintainGeometry make it easier for geometry managers to deal with slaves whose masters are not their parents. Three problems arise if the master for a slave is not its parent:

[1]

The x- and y-position of the slave must be translated from the coordinate system of the master to that of the parent before positioning the slave.

[2]

If the master window, or any of its ancestors up to the slave’s parent, is moved, then the slave must be repositioned within its parent in order to maintain the correct position relative to the master.

[3]

If the master or one of its ancestors is mapped or unmapped, then the slave must be mapped or unmapped to correspond.

None of these problems is an issue if the parent and master are the same. For example, if the master or one of its ancestors is unmapped, the slave is automatically removed by the screen by X.

Tk_MaintainGeometry deals with these problems for slaves whose masters are not their parents, as well as handling the simpler case of slaves whose masters are their parents. Tk_MaintainGeometry is typically called by a window manager once it has decided where a slave should be positioned relative to its master. Tk_MaintainGeometry translates the coordinates to the coordinate system of slave’s parent and then moves and resizes the slave appropriately. Furthermore, it remembers the desired position and creates event handlers to monitor the master and all of its ancestors up to (but not including) the slave’s parent. If any of these windows is moved, mapped, or unmapped, the slave will be adjusted so that it is mapped only when the master is mapped and its geometry relative to the master remains as specified by x, y, width, and height.

When a window manager relinquishes control over a window, or if it decides that it does not want the window to appear on the screen under any conditions, it calls Tk_UnmaintainGeometry. Tk_UnmaintainGeometry unmaps the window and cancels any previous calls to Tk_MaintainGeometry for the masterslave pair, so that the slave’s geometry and mapped state are no longer maintained automatically. Tk_UnmaintainGeometry need not be called by a geometry manager if the slave, the master, or any of the master’s ancestors is destroyed: Tk will call it automatically.

If Tk_MaintainGeometry is called repeatedly for the same masterslave pair, the information from the most recent call supersedes any older information. If Tk_UnmaintainGeometry is called for a masterslave pair that is is not currently managed, the call has no effect.

KEYWORDS

geometry manager, map, master, parent, position, slave, unmap






Opportunity


Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.

Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.





Free Software


Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.


Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.





Free Books


The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.


Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.





Education


Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.


Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.