Tk::Adjuster 804.027

Tk::Adjuster module will allow size of packed widgets to be adjusted by user.

SYNOPSIS

use Tk::Adjuster;
$adjuster = $widget->Adjuster(?options?);

WIDGET-SPECIFIC OPTIONS

Name: restore
Class: Restore
Switch: -restore

Specifies a boolean value that determines whether the Adjuster should forcibly attempt to make room for itself (by reducing the size of its managed widget) when it is unmapped (for example, due to a size change in a top level window). The default value is 1.

Name: side
Class: Side
Switch: -side

Specifies the side on which the managed widget lies relative to the Adjuster. In conjunction with the pack geometry manager, this relates to the side of the master against which the managed widget and the Adjuster are packed. Must be left, right, top, or bottom. Defaults to top.

Name: widget
Class: Widget
Switch: -widget

Specifies the widget which is to be managed by the Adjuster.

Tk::Adjuster is a Frame containing a "line" and a "blob".

Dragging with Mouse Button-1 results in a line being dragged to indicate new size. Releasing Button-1 submits GeometryRequests on behalf of the managed widget which will cause the packer to change the widgets size.

If Drag is done with Shift button down, then GeometryRequests are made in "real time" so that text-flow effects can be seen, but as a lot more work is done behaviour may be sluggish.

If widget is packed with -side => left or -side => right then width is adjusted. If packed -side => top or -side => bottom then height is adjusted.

packPropagate is turned off for the master window to prevent adjustment changing overall window size. Similarly packPropagate is turned off for the managed widget if it has things packed inside it. This is so that the GeometryRequests made by Tk::Adjuster are not overridden by pack.

In addition, the managed widget is made non-expandable to prevent the geometry manager reallocating freed space in the master back to the managed widget. Note however that expansion is turned off only after the Adjuster is mapped, which allows the managed widget to expand naturally on window creation.

The Tk::Widget method, packAdjust, calls pack on the widget, then creates an instance of Tk::Adjuster, and packs that "after" the widget. Its use has two disadvantages however: the Adjuster widget is not made available to the caller, and options cannot be set on the Adjuster. For these reasons, the Tk::Adjuster method, packAfter is preferred, but packAdjust is retained for backwards compatibility.