canvas::zoom - Zoom control for canvas::sqmap
package require Tcl 8.4
package require Tk 8.4
package require snit
package require uevent::onidle
package require canvas::zoom ?0.2.1?
::canvas::zoom pathName ?options?
This package provides a widget to enable the user of a map display
to control the zoom level.
- ::canvas::zoom pathName ?options?
- Creates the zoom control widget pathName and configures it. The
methods and options supported by the new widget are described in the
following sections.
The result of the command is pathName.
- -orient
- The value for this option is either vertical, or horizontal,
specifying the orientation of the major axis of the widget. The default is
vertical.
- -levels
- The value for this option is a non-negative integer. It specifies the
number of zoom levels to support.
- -variable
- The value for this option is the name of a global or namespaced variable
which is connected with the widget. changes to the zoom level made the
widget are propagated to this variable, and in turn changes to the
variable are imported into the widget.
- -command
- This option specifies a command prefix. This callback will be invoked
whenever the zoom level is changed. It is called with two additional
arguments, the zoom control widget, and the new zoom level, in this
order.
The widget supports no methods beyond the standard
(configure, cget, etc.).