|Allegro CL version 8.2|
Moderately revised from 8.1.
The class of tab-control controls.
An instance of the tab-control class. This control allows you to create a set of pages of controls and group them in related sub-groups on each tab. The Options dialog dialog is an example of a tab-control.
The individual tabs are instances of the
tab-info class. The range property contains a list
tab-info objects, and
the value property contains
the name of the selected
tab-info. Setting the value property to a different name will select a
different tab. A tab can be added to an existing tab-control by
calling add-tab, or
removed by calling remove-tab. A widget can be added to
an existing tab by calling add-component-to-tab, or removed by
Other properties that are unique to the
tab-control include tab-height, tab-width, fixed-width, single-line, focus-on-click, ragged-right, tab-side, button-style, and tabs-are-draggable.
When creating tab-controls interactively on form windows, tab-controls allow overlap on their borders even when the allow-component-overlap option is turned off. Objects overlapping a tab may or may not appear in the range and tab-info(s) for the tabs they overlap, so use this feature with care.
In Windows, the tab-order of the controls on a parent window is always
the same as the front-to-back occlusion order of the controls. This
means that a
tab-control must be positioned in
the tab order after all of the widgets that are on it, or else it will
cover those widgets. This is handled automatically when designing a
form window interactively, but it must be handled by the application
when creating a dialog programmatically. See tab-position.
The generic functions select-adjacent-tab and select-recent-tab are useful for keyboard shortcuts that select nearby or recently-selected tabs of a tab-control.
Click the tab-control tool on of the Component toolbar. Move the mouse cursor to the part of the form where you want to place the control, and click again. The control will appear with colored resizing handles.
If you are creating a dialog programmatically rather than laying it out interactively as a form, then there are two ways to add widgets to tab-control tabs. One way is to associate the widgets with each other when creating all of them together. The other way is to call add-component-to-tab to add a widget to a pre-existing tab-control.
First we have is an example of the first approach. This code will
create a window that contains a tab-control that has a
button widget on its
first tab. To make the button appear only when its tab is selected,
the tab-control and the button must be associated with each other. So
the button points to its tab by specifying a
:tab-control initarg of
:one), which is a list of the name of the tab-control
followed by the name of the tab. Conversely, the first tab points to
the button by specifying a
:widgets initarg of
(:first-button), which is a list of all of the
widgets that are on that tab.
(setq my-window (make-window :my-window :class 'dialog :width 300 :height 300 :dialog-items (list (make-instance 'button :left 80 :top 100 :width 100 :height 30 :name :first-button :title "~First" :tab-control '(:my-tab-control :first-tab)) (make-instance 'tab-control :left 50 :top 50 :width 200 :height 150 :name :my-tab-control :value :first-tab :range (list (make-instance 'tab-info :name :first-tab :label "One" :widgets '(:first-button)) (make-instance 'tab-info :name :second-tab :label "Two") (make-instance 'tab-info :name :third-tab :label "Three"))))))
The other way to add a widget to a tab programmatically is to call add-component-to-tab. This is useful if you want to create a tab-control and then add widgets to it later. (Similarly, remove-component-from-tab will remove a widget from a tab.)
This example would add another
button widget to the tab-control
that was created above, this time to the second tab.
(add-component-to-tab (find-component :my-tab-control my-window) :second-tab (make-instance 'button :left 100 :top 100 :width 100 :height 30 :name :second-button :title "~Second"))
Controls can only be resized and moved on forms during the design stage; the size and location of everything is fixed on a running form.
Resize the control by clicking the mouse cursor and dragging one of the handles to the new size-point. Release the mouse key when you are satisfied with the new size.
Resizing the tab-control won't mean proportional changes in the size of the characters of the labels of the tabs. Change the font property if you want to change the size of the actual characters displayed.
Move the control by clicking anywhere on it except a resizing handle and dragging it to a new location on the form. Release the mouse key when you are ready to place the control.
Moving a tab-control means dragging all of the contained objects along with it.
When designing a dialog using a form, drag controls onto the individual tabs and position them. After you have added controls to each tab, you will be able to see their names in the expanded portions of the Inspector. To see the names of the controls placed on each tab in the Inspector:
tab-infoentries, one per line. There will be one
tab-infofor each tab in your tab-control. They will be numbered from 0 to n for (n+1) tabs.
You can also inspect the tab-infos programmatically by searching your
code for calls to make-instance with
for the particular tab-control you are working on.
The generic funcion highlight-tab allows you to highlight one or more tabs on a tab-control.
See About how to get sample code for creating controls in cgide.htm, which explains how to use the IDE to create such code.
A diagram of window and widget classes is shown in Widget and window classes in cgide.htm.
uses a single row of tabs, and specifying the single-line property will have no effect. You
can scroll a tab-control quickly by holding the mouse button down on
the scroll arrow, but only if the widget's focus-on-click property is true, since otherwise
Common Graphics will move the keyboard focus to a widget on a tab. If
it is tedious to scroll to all of the tabs, you might consider using a
instead, as we did for the IDE's Class Browser.
Copyright (c) 1998-2012, Franz Inc. Oakland, CA., USA. All rights reserved.
This page has had moderate revisions compared to the 8.1 page.
|Allegro CL version 8.2|
Moderately revised from 8.1.