Description
PyGTK via GTK+ provides
resource file mechanism for configuring various aspects of the operation of
a program at runtime.
Default files
An application can cause GTK+ to parse a
specific RC file by calling the gtk.rc_parse()
function. In addition to this, certain files will be read at the end of
GTK+ initialization. Unless modified, the files looked
for will be <SYSCONFDIR>/gtk-2.0/gtkrc and
.gtkrc-2.0 in the users home directory. (<SYSCONFDIR> defaults to
/usr/local/etc.) The set of these default files can be
retrieved with the gtk.rc_get_default_files()
function and modified with the gtk.rc_add_default_file()
and gtk.rc_set_default_files()
functions. Additionally, the GTK_RC_FILES environment
variable can be set to a list of files in order to overwrite the set of
default files at runtime.
For each RC file, in addition to the file itself,
GTK+ will look for a locale-specific file that will be
parsed after the main file. For instance, if LANG is set to
ja_JP.ujis, when loading the default file
~/.gtkrc then GTK+ looks for
~/.gtkrc.ja_JP and ~/.gtkrc.ja,
and parses the first of those that exists.
Pathnames and patterns
A resource file defines a number of styles and key bindings and
attaches them to particular widgets. The attachment is done by the widget,
widget_class, and class declarations. As an example of such a
statement:
widget "mywindow.*.GtkEntry" style "my-entry-class"
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attaches the style "my-entry-class" to all widgets whose widget class
matches the pattern "mywindow.*.GtkEntry". The patterns here are given in
the standard shell glob syntax. The "?" wildcard matches any character,
while "*" matches zero or more of any character. The three types of matching
are against the widget path, the class path and the class hierarchy. Both
the widget and the class paths consists of a "." separated list of all the
parents of the widget and the widget itself from outermost to innermost. The
difference is that in the widget path, the name assigned by the set_name()
method is used if present, otherwise the class name of the widget, while for
the widget path, the class name is always used. So, if you have a gtk.Entry named
"myentry", inside of a of a window named "mywindow", then the widget path
is: "mwindow.GtkHBox.myentry" while the class path is:
"GtkWindow.GtkHBox.GtkEntry".
Matching against class is a little different. The pattern match is
done against all class names in the widgets class hierarchy (not the layout
hierarchy) in sequence, so the pattern:
class "GtkButton" style "my-style"
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will match not just gtk.Button widgets,
but also gtk.ToggleButton
and gtk.CheckButton
widgets, since those classes derive from gtk.Button.
Toplevel declarations
An RC file is a text file which is composed of a sequence of
declarations. '#' characters delimit comments and the portion of a line
after a '#' is ignored when parsing an RC file. The possible toplevel
declarations are:
binding name { ... } | Declares a binding set. |
class pattern [ style | binding [ : priority ]] name | Specifies a style or binding set for a particular branch
of the inheritance hierarchy. |
include filename | Parses another file at this point. If
filename is not an absolute filename, it is searched
in the directories of the currently open RC files. GTK+
also tries to load a locale-specific variant of the included file. |
module_path path | Sets a path (a list of directories separated by colons)
that will be searched for theme engines referenced in RC files. |
pixmap_path path | Sets a path (a list of directories separated by colons)
that will be searched for pixmaps referenced in RC files. |
style name [ = parent ] { ... } | Declares a style. |
widget pattern [ style | binding [ : priority ]] name | Specifies a style or binding set for a particular group
of widgets by matching on the widget pathname. |
widget_class pattern [ style | binding [ : priority ]] name | Specifies a style or binding set for a particular group
of widgets by matching on the class pathname. |
Styles
A RC style is specified by a style declaration in a RC file, and
then bound to widgets with a widget,
widget_class, or class declaration.
All styles applying to a particular widget are composited together with
widget declarations overriding widget_class declarations
which, in turn, override class declarations. Within each
type of declaration, later declarations override earlier ones. Within a
style declaration, the possible elements are:
bg[state] = color | Sets the color used for the background of most
widgets. |
fg[state] = color | Sets the color used for the foreground of most
widgets. |
base[state] = color | Sets the color used for the background of widgets
displaying editable text. This color is used for the background of, among
others, gtk.TextView and
gtk.Entry. |
text[state] = color | Sets the color used for foreground of widgets using
base for the background color. |
bg_pixmap[state] = pixmap | Sets a background pixmap to be used in place of the
bg color (or for gtk.TextView, in
place of the base color). The special value
"<parent>" may be used to indicate that the widget should use the same
background pixmap as its parent. The special value "<none>" may be
used to indicate no background pixmap. |
font = font | Sets the font for a widget. font must be a XLFD font
description, e.g.
"-*-helvetica-medium-r-normal--10-*-*-*-*-*-*-*". |
fontset = font | Sets the fontset for a widget. Overrides any font
declarations. font must be a comma-separated list of XLFD font descriptions,
e.g. "-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-240,
-JIS-Fixed-Medium-R-Normal--26-180-100-100-C-120,
-GB-Fixed-Medium-R-Normal--26-180-100-100-C-240,
-Adobe-Courier-Bold-R-Normal--25-180-100-100-M-150". |
font_name = font | Sets the font for a widget. Overrides any
font or fontset declarations.
font must be a Pango font name, e.g. "Sans Italic
10". |
stock["stock-id"] = { icon source specifications } | Defines the icon for a stock item. |
engine "engine" { engine-specific settings } | Defines the engine to be used when drawing with this
style. |
class::property = value | Sets a style property for a widget
class. |
The colors and background pixmaps are specified as a function of
the state of the widget. The states are:
NORMAL | A color used for a widget in its normal state. |
ACTIVE | A variant of the NORMAL color used
when the widget is in the gtk.STATE_ACTIVE state, and
also for the trough of a gtk.Scrollbar,
tabs of a gtk.Notebook other
than the current tab and similar areas. Frequently, this should be a darker
variant of the NORMAL color. |
PRELIGHT | A color used for widgets in the
gtk.STATE_PRELIGHT state. This state is the used for
gtk.Button and
gtk.MenuItem
widgets that have the mouse cursor over them, and for their
children. |
SELECTED | A color used to highlight data selected by the user. for
instance, the selected items in a list widget, and the selection in an
editable widget. |
INSENSITIVE | A color used for the background of widgets that have been
set insensitive with the set_sensitive()
method. |
Colors can be specified as a string containing a color name (from
the X color database /usr/lib/X11/rgb.txt), in one of
the hexadecimal forms #rrrrggggbbbb,
#rrrgggbbb, #rrggbb, or
#rgb, where r, g
and b are hex digits, or they can be specified as a
triplet { r, g, b}, where r,
g and b are either integers in the
range 0-65635 or floats in the range 0.0-1.0.
In a stock definition, icon sources are specified as a 4-tuple of
image filename, text direction, widget state, and size, in that order. Each
icon source specifies an image filename to use with a given direction,
state, and size. The * character can be used as a wildcard, and if
direction-state-size are omitted they default to *. So for example, the
following specifies different icons to use for left-to-right and
right-to-left languages:
stock["my-stock-item"] =
{
{ "itemltr.png", LTR, *, * },
{ "itemrtl.png", RTL, *, * }
}
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This could be abbreviated as follows:
stock["my-stock-item"] =
{
{ "itemltr.png", LTR },
{ "itemrtl.png", RTL }
}
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You can specify custom icons for specific sizes, as
follows:
stock["my-stock-item"] =
{
{ "itemmenusize.png", *, *, "gtk-menu" },
{ "itemtoolbarsize.png", *, *, "gtk-large-toolbar" }
{ "itemgeneric.png" } /* implicit *, *, * as a fallback */
}
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The sizes that come with GTK+ itself are
"gtk-menu", "gtk-small-toolbar", "gtk-large-toolbar", "gtk-button",
"gtk-dialog". Applications can define other sizes. It's also possible to use
custom icons for a given state, for example:
stock["my-stock-item"] =
{
{ "itemprelight.png", *, PRELIGHT },
{ "iteminsensitive.png", *, INSENSITIVE },
{ "itemgeneric.png" } /* implicit *, *, * as a fallback */
}
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When selecting an icon source to use, GTK+ will
consider text direction most important, state second, and size third. It
will select the best match based on those criteria. If an attribute matches
exactly (e.g. you specified PRELIGHT or specified the
size), GTK+ won't modify the image; if the attribute
matches with a wildcard, GTK+ will scale or modify the
image to match the state and size the user requested.
Key bindings
Key bindings allow the user to specify actions to be taken on
particular key presses. The form of a binding set declaration is:
binding name {
bind key {
signalname (param, ...)
...
}
...
}
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key is a string consisting of a series of
modifiers followed by the name of a key. The modifiers can be:
- <alt>
- <control>
- <mod1>
- <mod2>
- <mod3>
- <mod4>
- <mod5>
- <release>
- <shft>
- <shift>
<shft> is an alias for <shift> and <alt> is an
alias for <mod1>.
The action that is bound to the key is a sequence of signal names
(strings) followed by parameters for each signal. The signals must be action
signals. Each parameter can be a float, integer, string, or unquoted string
representing an enumeration value. The types of the parameters specified
must match the types of the parameters of the signal. Binding sets are
connected to widgets in the same manner as styles, with one addition. A
priority can be specified for each pattern, and within each type of pattern,
binding sets override other binding sets first by priority, and only then by
order of specification. (Later overrides earlier). The priorities that can
be specified are (highest to lowest):
- highest
- rc
- theme
- application
- gtk
- lowest
rc is the default for bindings read from an RC
file, theme is the default for bindings read from theme
RC files, application should be used for bindings an
application sets up, and gtk is used for bindings that
GTK+ creates internally.