racket/collects/scribblings/gui/frame-class.scrbl

313 lines
10 KiB
Racket

#lang scribble/doc
@(require "common.ss")
@defclass/title[frame% object% (top-level-window<%>)]{
A frame is a top-level container window. It has a title bar (which
displays the frame's label), an optional menu bar, and an optional
status line.
Under Windows, both Multiple Document Interface (MDI) and Single
Document Interface (SDI) frames are supported.
@defconstructor[([label label-string?]
[parent (or/c (is-a?/c frame%) false/c) #f]
[width (or/c (integer-in 0 10000) false/c) #f]
[height (or/c (integer-in 0 10000) false/c) #f]
[x (or/c (integer-in -10000 10000) false/c) #f]
[y (or/c (integer-in -10000 10000) false/c) #f]
[style (listof (one-of/c 'no-resize-border 'no-caption
'no-system-menu 'hide-menu-bar
'mdi-parent 'mdi-child
'toolbar-button 'float 'metal)) null]
[enabled any/c #t]
[border (integer-in 0 1000) 0]
[spacing (integer-in 0 1000) 0]
[alignment (list/c (one-of/c 'left 'center 'right)
(one-of/c 'top 'center 'bottom))
'(center top)]
[min-width (integer-in 0 10000) _graphical-minimum-width]
[min-height (integer-in 0 10000) _graphical-minimum-height]
[stretchable-width any/c #t]
[stretchable-height any/c #t])]{
The @scheme[label] string is displayed in the frame's title
bar. If the frame's label is changed (see @method[window<%>
set-label]), the title bar is updated.
The @scheme[parent] argument can be @scheme[#f] or an existing
frame. Under Windows, if @scheme[parent] is an existing frame,
the new frame is always on top of its parent. Also, the
@scheme[parent] frame may be an MDI parent frame from a new MDI
child frame. Under Windows and X (for many window managers), a
frame is iconized when its parent is iconized.
If @scheme[parent] is @scheme[#f], then the eventspace for the
new frame is the current eventspace, as determined by
@scheme[current-eventspace]. Otherwise, @scheme[parent]'s
eventspace is the new frame's eventspace.
If the @scheme[width] or @scheme[height] argument is not
@scheme[#f], it specifies an initial size for the frame (in
pixels) assuming that it is larger than the minimum size,
otherwise the minimum size is used.
If the @scheme[x] or @scheme[y] argument is not @scheme[#f], it
specifies an initial location for the frame. Otherwise, a
location is selected automatically (tiling frames and dialogs as
they are created).
The @scheme[style] flags adjust the appearance of the frame on
some platforms:
@itemize{
@item{@scheme['no-resize-border] --- omits the resizeable border
around the window (Windows, X MWM) or grow box in the bottom right
corner (Mac OS X)}
@item{@scheme['no-caption] --- omits the title bar for the frame
(Windows, X MWM)
(X Gnome, X KDE: the frame decoration is omitted completely when
@scheme['no-resize-border] and @scheme['no-caption] are combined.)}
@item{@scheme['no-system-menu] --- omits the system menu
(Windows)}
@item{@scheme['mdi-child] --- creates the frame as a MDI
(multiple document interface) child frame, mutually exclusive with
@scheme['mdi-parent] (Windows)}
@item{@scheme['mdi-parent] --- creates the frame as a MDI
(multiple document interface) parent frame, mutually exclusive with
@scheme['mdi-child] (Windows)}
@item{@scheme['toolbar-button] --- includes a toolbar button on the
frame's title bar (Mac OS X); a click on the toolbar button triggers
a call to @method[frame% on-toolbar-button-click]}
@item{@scheme['hide-menu-bar] --- hides the menu bar and dock when
the frame is active (Mac OS X)}
@item{@scheme['float] --- causes the frame to stay in front of all
other non-floating windows (Windows and Mac OS X always, X when
combined with @scheme['no-caption]); under Mac OS X, a floating frame
shares the focus with an active non-floating frame; when this style
is combined with @scheme['no-caption], then showing the frame does
not cause the keyboard focus to shift to the window, and under X,
clicking the frame does not move the focus; under Windows, a floating
frame has no taskbar button}
@item{@scheme['metal] --- draws the frame with a brushed-metal
background (Mac OS X); this style is ignored when
@scheme['no-caption] is specified}
}
If the @scheme['mdi-child] style is specified, the @scheme[parent] must be
a frame with the @scheme['mdi-parent] style, otherwise @|MismatchExn|.
Even if the frame is not shown, a few notification events may be
queued for the frame on creation. Consequently, the new frame's
resources (e.g., memory) cannot be reclaimed until some events are
handled, or the frame's eventspace is shut down.
@WindowKWs[] @AreaContKWs[] @AreaKWs[]
}
@defmethod[(create-status-line)
void?]{
Creates a status line at the bottom of the frame. The width of the
status line is the whole width of the frame (adjusted automatically
when resizing), and the height and text size are platform-specific.
See also @method[frame% set-status-text].
}
@defmethod[(get-menu-bar)
(or/c (is-a?/c menu-bar%) false/c)]{
Returns the frame's menu bar, or @scheme[#f] if none has been created
for the frame.
}
@defmethod[(has-status-line?)
boolean?]{
Returns @scheme[#t] if the frame's status line has been created,
@scheme[#f] otherwise. See also @method[frame% create-status-line].
}
@defmethod[(iconize [iconize? any/c])
void?]{
Iconizes (@as-index{minimizes}) or deiconizes (restores) the
frame. Deiconizing brings the frame to the front.
@Unmonitored[@elem{A frame's iconization} @elem{the user} @elem{a
frame has been iconized} @elem{@method[frame% is-iconized?]}]
}
@defmethod[(is-iconized?)
boolean?]{
Returns @scheme[#t] if the frame is iconized (minimized), @scheme[#f]
otherwise.
}
@defmethod[(is-maximized?)
boolean?]{
Under Windows and Mac OS X, returns @scheme[#t] if the frame is
maximized, @scheme[#f] otherwise. Under X, the result is always
@scheme[#f].
}
@defmethod[(maximize [maximize? any/c])
void?]{
@methspec{
Maximizes or restores the frame under Windows and Mac OS X; the
frame's show state is not affected. Under Windows, an iconized frame
cannot be maximized or restored.
@MonitorMethod[@elem{A window's maximization} @elem{the user} @elem{@method[window<%> on-size]} @elem{size}]
}
@methimpl{
If @scheme[maximize?] is @scheme[#f], the window is restored, otherwise
it is maximized.
}}
@defmethod*[([(modified)
boolean?]
[(modified [modified? any/c])
void?])]{
Gets or sets the frame's modification state as reflected to the user.
Under Mac OS X, the modification state is reflected as a dot in the
frame's close button. Under Windows and X, the modification state is
reflected by an asterisk at the end of the frame's displayed title.
}
@defmethod[(on-mdi-activate [active? any/c])
void?]{
Called under Windows when a MDI-child frame becomes the active frame
within its parent (in which case the argument is @scheme[#t]), or when
the child frame ceases to be the active frame (in which case the
argument is @scheme[#f]).
MDI activation is different from keyboard-focus activation. If the
parent frame is the frontmost top-level frame, so that the MDI child
gets or loses the keyboard focus, then a separate
@method[top-level-window<%> on-activate] notification is sent to the MDI-child frame.
}
@defmethod[(on-menu-char [event (is-a?/c key-event%)])
boolean?]{
If the frame has a menu bar with keyboard shortcuts, and if the key
event includes a Control, Alt, Option, Meta, Command, Shift, or
Function key, then @method[frame% on-menu-char] attempts to match the
given event to a menu item. If a match is found, @scheme[#t] is
returned, otherwise @scheme[#f] is returned.
When the match corresponds to a complete shortcut combination, the
menu item's callback is called (before
@method[frame% on-menu-char] returns).
If the event does not correspond to a complete shortcut combination,
the event may be handled anyway if it corresponds to a mnemonic in the
menu bar (i.e., an underlined letter in a menu's title, which is
installed by including an ampersand in the menu's label). If a
mnemonic match is found, the keyboard focus is moved to the menu bar
(selecting the menu with the mnemonic), and @scheme[#t] is returned.
}
@defmethod[#:mode override
(on-subwindow-char [receiver (is-a?/c window<%>)]
[event (is-a?/c key-event%)])
boolean?]{
Returns the result of
@schemeblock[
(or (send this (:: frame% on-menu-char) event)
(send this (:: top-level-window<%> on-system-menu-char) event)
(send this (:: top-level-window<%> on-traverse-char) event))
]
}
@defmethod[(on-toolbar-button-click)
void?]{
Under Mac OS X, called when the user clicks the toolbar button on a
frame created with the @indexed-scheme['toolbar-button] style.
}
@defmethod[(set-icon [icon (is-a?/c bitmap%)]
[mask (is-a?/c bitmap%) #f]
[which (one-of/c 'small 'large 'both) 'both])
void?]{
Sets the large or small icon bitmap for this frame. Future changes to
the bitmap do not affect the frame's icon.
The icon is used in a platform-specific way:
@itemize{
@item{Windows --- the small icon is used for the frame's icon (in the
top-left) and in the task bar, and the large icon is used for
the Alt-Tab task switcher.}
@item{Mac OS X --- both icons are ignored.}
@item{X --- many window managers use the small icon in the same way
as Windows, and others use the small icon when iconifying the
frame; the large icon is ignored.}
}
The bitmap for either icon can be any size, but most platforms scale
the small bitmap to 16 by 16 pixels and the large bitmap to 32 by 32
pixels.
If a mask bitmap is not provided, then the entire (rectangular) bitmap
is used as an icon.
If a mask bitmap is provided, the mask must be monochrome. In the mask
bitmap, use black pixels to indicate the icon's region and use white
pixels outside the icon's region. In the icon bitmap, use black
pixels for the region outside the icon.
}
@defmethod[(set-status-text [text string])
void?]{
Sets the frame's status line text and redraws the status line. See
also @method[frame% create-status-line].
}}