The methods in this section all deal with the position of a widget.
determine which widget is at the point (x, y), use the
$which = $widget->containing($x, $y);
$y coordinates must be
relative to the root window (or on a Microsoft Windows system, the
desktop). An empty string is returned if there is no widget found at
those coordinates. If there are several widgets located at those
coordinates, the one closest to the front is returned.
You can get the coordinates of the
upper-left corner of a widget by using the
ymethods. The coordinates
they return are relative to the parent of the widget:
$x = $widget->x; $y = $widget->y;
To get the coordinates relative to the
root window, use
rooty on the widget:
$x = $widget->rootx; $y = $widget->rooty;
The coordinates refer to the upper-left corner of the widget.
If you have a virtual desktop, there are special methods that give coordinates relative to the virtual desktop. Virtual desktops are very common on the X Window System (such as the fvwm and tvtwm window managers), but they exist on Microsoft Windows as well.
To determine the height and width of the
virtual desktop, use the
$height = $widget->vrootheight; $width = $widget->vrootwidth;
To get the coordinates of the widget’s upper-left corner ...