interface-display

interface-display Generic Function

Summary

The function called to display an interface on screen.

Package

capi

Signature

interface-display interface

Arguments

interface⇩

An instance of a subclass of interface.

Description

The generic function interface-display is called by display to display an interface on screen.

The primary method for interface actually does the work. You can add :before methods on your own interface classes for code that needs to be executed just before the interface appears, and :after methods for code that needs to be executed just after the interface appears.

interface-display is useful when you need to make changes to the interface which require it to be already be created. Font queries and loading images are typical cases.

Notes

interface-display is called in the process of interface.
interface-display is not called when interface is displayed as a dialog. Another way to run code before it appears on screen is to supply a create-callback for interface.

Examples

This example shows how interface-display can be used to set the initial selection in a choice whose items are computed at display-time:

(capi:define-interface my-tree ()
  ((favorite-color :initform :blue))
  (:panes
   (tree
    capi:tree-view
    :roots '(:red :blue :green)
    :print-function
    'string-capitalize))
  (:default-initargs 
   :width 200 
   :height 200))
 
(defmethod capi:interface-display :after 
  ((self my-tree))
  (with-slots (tree favorite-color) self
    (setf (capi:choice-selected-item tree)
          favorite-color)))
 
(capi:display (make-instance 'my-tree))