GtkCssProvider

GtkCssProvider — CSS-like styling for widgets

Signals

Object Hierarchy

    GBoxed
    ╰── GtkCssSection
    GObject
    ╰── GtkCssProvider

Implemented Interfaces

GtkCssProvider implements GtkStyleProvider and GtkStyleProviderPrivate.

Includes

#include <gtk/gtk.h>

Description

GtkCssProvider is an object implementing the GtkStyleProvider interface. It is able to parse CSS-like input in order to style widgets.

An application can make GTK+ parse a specific CSS style sheet by calling gtk_css_provider_load_from_file() or gtk_css_provider_load_from_resouce() and adding the provider with gtk_style_context_add_provider() or gtk_style_context_add_provider_for_screen().

In addition, certain files will be read when GTK+ is initialized. First, the file $XDG_CONFIG_HOME/gtk-3.0/gtk.css is loaded if it exists. Then, GTK+ loads the first existing file among XDG_DATA_HOME/themes/theme-name/gtk-VERSION/gtk.css, $HOME/.themes/theme-name/gtk-VERSION/gtk.css, $XDG_DATA_DIRS/themes/theme-name/gtk-VERSION/gtk.css and DATADIR/share/themes/THEME/gtk-VERSION/gtk.css, where THEME is the name of the current theme (see the #GtkSettings:gtk-theme-name setting), DATADIR is the prefix configured when GTK+ was compiled (unless overridden by the GTK_DATA_PREFIX` environment variable), and VERSION is the GTK+ version number. If no file is found for the current version, GTK+ tries older versions all the way back to 3.0.

In the same way, GTK+ tries to load a gtk-keys.css file for the current key theme, as defined by “gtk-key-theme-name”.

Functions

gtk_css_provider_get_default ()

GtkCssProvider *
gtk_css_provider_get_default (void);

Returns the provider containing the style settings used as a fallback for all widgets.

Returns

The provider used for fallback styling. This memory is owned by GTK+, and you must not free it.

[transfer none]


gtk_css_provider_get_named ()

GtkCssProvider *
gtk_css_provider_get_named (const gchar *name,
                            const gchar *variant);

Loads a theme from the usual theme paths

Parameters

name

A theme name

 

variant

variant to load, for example, "dark", or NULL for the default.

[allow-none]

Returns

a GtkCssProvider with the theme loaded. This memory is owned by GTK+, and you must not free it.

[transfer none]


gtk_css_provider_load_from_data ()

gboolean
gtk_css_provider_load_from_data (GtkCssProvider *css_provider,
                                 const gchar *data,
                                 gssize length,
                                 GError **error);

Loads data into css_provider , and by doing so clears any previously loaded information.

Parameters

css_provider

a GtkCssProvider

 

data

CSS data loaded in memory.

[array length=length][element-type guint8]

length

the length of data in bytes, or -1 for NUL terminated strings. If length is not -1, the code will assume it is not NUL terminated and will potentially do a copy.

 

error

return location for a GError, or NULL.

[out][allow-none]

Returns

TRUE. The return value is deprecated and FALSE will only be returned for backwards compatibility reasons if an error is not NULL and a loading error occurred. To track errors while loading CSS, connect to the “parsing-error” signal.


gtk_css_provider_load_from_file ()

gboolean
gtk_css_provider_load_from_file (GtkCssProvider *css_provider,
                                 GFile *file,
                                 GError **error);

Loads the data contained in file into css_provider , making it clear any previously loaded information.

Parameters

css_provider

a GtkCssProvider

 

file

GFile pointing to a file to load

 

error

return location for a GError, or NULL.

[out][allow-none]

Returns

TRUE. The return value is deprecated and FALSE will only be returned for backwards compatibility reasons if an error is not NULL and a loading error occurred. To track errors while loading CSS, connect to the “parsing-error” signal.


gtk_css_provider_load_from_path ()

gboolean
gtk_css_provider_load_from_path (GtkCssProvider *css_provider,
                                 const gchar *path,
                                 GError **error);

Loads the data contained in path into css_provider , making it clear any previously loaded information.

Parameters

css_provider

a GtkCssProvider

 

path

the path of a filename to load, in the GLib filename encoding

 

error

return location for a GError, or NULL.

[out][allow-none]

Returns

TRUE. The return value is deprecated and FALSE will only be returned for backwards compatibility reasons if an error is not NULL and a loading error occurred. To track errors while loading CSS, connect to the “parsing-error” signal.


gtk_css_provider_load_from_resource ()

void
gtk_css_provider_load_from_resource (GtkCssProvider *css_provider,
                                     const gchar *resource_path);

Loads the data contained in the resource at resource_path into the GtkCssProvider, clearing any previously loaded information.

To track errors while loading CSS, connect to the “parsing-error” signal.

Parameters

css_provider

a GtkCssProvider

 

resource_path

a GResource resource path

 

Since: 3.16


gtk_css_provider_new ()

GtkCssProvider *
gtk_css_provider_new (void);

Returns a newly created GtkCssProvider.

Returns

A new GtkCssProvider


gtk_css_provider_to_string ()

char *
gtk_css_provider_to_string (GtkCssProvider *provider);

Converts the provider into a string representation in CSS format.

Using gtk_css_provider_load_from_data() with the return value from this function on a new provider created with gtk_css_provider_new() will basically create a duplicate of this provider .

Parameters

provider

the provider to write to a string

 

Returns

a new string representing the provider .

Since: 3.2


gtk_css_section_get_end_line ()

guint
gtk_css_section_get_end_line (const GtkCssSection *section);

Returns the line in the CSS document where this section end. The line number is 0-indexed, so the first line of the document will return 0. This value may change in future invocations of this function if section is not yet parsed completely. This will for example happen in the GtkCssProvider::parsing-error signal. The end position and line may be identical to the start position and line for sections which failed to parse anything successfully.

Parameters

section

the section

 

Returns

the line number

Since: 3.2


gtk_css_section_get_end_position ()

guint
gtk_css_section_get_end_position (const GtkCssSection *section);

Returns the offset in bytes from the start of the current line returned via gtk_css_section_get_end_line(). This value may change in future invocations of this function if section is not yet parsed completely. This will for example happen in the GtkCssProvider::parsing-error signal. The end position and line may be identical to the start position and line for sections which failed to parse anything successfully.

Parameters

section

the section

 

Returns

the offset in bytes from the start of the line.

Since: 3.2


gtk_css_section_get_file ()

GFile *
gtk_css_section_get_file (const GtkCssSection *section);

Gets the file that section was parsed from. If no such file exists, for example because the CSS was loaded via gtk_css_provider_load_from_data() , then NULL is returned.

Parameters

section

the section

 

Returns

the GFile that section was parsed from or NULL if section was parsed from other data.

[transfer none]

Since: 3.2


gtk_css_section_get_parent ()

GtkCssSection *
gtk_css_section_get_parent (const GtkCssSection *section);

Gets the parent section for the given section . The parent section is the section that contains this section . A special case are sections of type GTK_CSS_SECTION_DOCUMENT. Their parent will either be NULL if they are the original CSS document that was loaded by gtk_css_provider_load_from_file() or a section of type GTK_CSS_SECTION_IMPORT if it was loaded with an import rule from a different file.

Parameters

section

the section

 

Returns

the parent section or NULL if none.

[nullable][transfer none]

Since: 3.2


gtk_css_section_get_section_type ()

GtkCssSectionType
gtk_css_section_get_section_type (const GtkCssSection *section);

Gets the type of information that section describes.

Parameters

section

the section

 

Returns

the type of section

Since: 3.2


gtk_css_section_get_start_line ()

guint
gtk_css_section_get_start_line (const GtkCssSection *section);

Returns the line in the CSS document where this section starts. The line number is 0-indexed, so the first line of the document will return 0.

Parameters

section

the section

 

Returns

the line number

Since: 3.2


gtk_css_section_get_start_position ()

guint
gtk_css_section_get_start_position (const GtkCssSection *section);

Returns the offset in bytes from the start of the current line returned via gtk_css_section_get_start_line().

Parameters

section

the section

 

Returns

the offset in bytes from the start of the line.

Since: 3.2


gtk_css_section_ref ()

GtkCssSection *
gtk_css_section_ref (GtkCssSection *section);

Increments the reference count on section .

Parameters

section

a GtkCssSection

 

Returns

section itself.

Since: 3.2


gtk_css_section_unref ()

void
gtk_css_section_unref (GtkCssSection *section);

Decrements the reference count on section , freeing the structure if the reference count reaches 0.

Parameters

section

a GtkCssSection

 

Since: 3.2

Types and Values

struct GtkCssProvider

struct GtkCssProvider;

GTK_CSS_PROVIDER_ERROR

#define GTK_CSS_PROVIDER_ERROR (gtk_css_provider_error_quark ())

Domain for GtkCssProvider errors.


enum GtkCssProviderError

Error codes for GTK_CSS_PROVIDER_ERROR.

Members

GTK_CSS_PROVIDER_ERROR_FAILED

Failed.

 

GTK_CSS_PROVIDER_ERROR_SYNTAX

Syntax error.

 

GTK_CSS_PROVIDER_ERROR_IMPORT

Import error.

 

GTK_CSS_PROVIDER_ERROR_NAME

Name error.

 

GTK_CSS_PROVIDER_ERROR_DEPRECATED

Deprecation error.

 

GTK_CSS_PROVIDER_ERROR_UNKNOWN_VALUE

Unknown value.

 

GtkCssSection

typedef struct _GtkCssSection GtkCssSection;

Defines a part of a CSS document. Because sections are nested into one another, you can use gtk_css_section_get_parent() to get the containing region.

Since: 3.2


enum GtkCssSectionType

The different types of sections indicate parts of a CSS document as parsed by GTK’s CSS parser. They are oriented towards the CSS Grammar, but may contain extensions.

More types might be added in the future as the parser incorporates more features.

Members

GTK_CSS_SECTION_DOCUMENT

The section describes a complete document. This section time is the only one where gtk_css_section_get_parent() might return NULL.

 

GTK_CSS_SECTION_IMPORT

The section defines an import rule.

 

GTK_CSS_SECTION_COLOR_DEFINITION

The section defines a color. This is a GTK extension to CSS.

 

GTK_CSS_SECTION_BINDING_SET

The section defines a binding set. This is a GTK extension to CSS.

 

GTK_CSS_SECTION_RULESET

The section defines a CSS ruleset.

 

GTK_CSS_SECTION_SELECTOR

The section defines a CSS selector.

 

GTK_CSS_SECTION_DECLARATION

The section defines the declaration of a CSS variable.

 

GTK_CSS_SECTION_VALUE

The section defines the value of a CSS declaration.

 

GTK_CSS_SECTION_KEYFRAMES

The section defines keyframes. See CSS Animations for details. Since 3.6

 

Since: 3.2

Signal Details

The “parsing-error” signal

void
user_function (GtkCssProvider *provider,
               GtkCssSection  *section,
               GError         *error,
               gpointer        user_data)

Signals that a parsing error occurred. the path , line and position describe the actual location of the error as accurately as possible.

Parsing errors are never fatal, so the parsing will resume after the error. Errors may however cause parts of the given data or even all of it to not be parsed at all. So it is a useful idea to check that the parsing succeeds by connecting to this signal.

Note that this signal may be emitted at any time as the css provider may opt to defer parsing parts or all of the input to a later time than when a loading function was called.

Parameters

provider

the provider that had a parsing error

 

section

section the error happened in

 

error

The parsing error

 

user_data

user data set when the signal handler was connected.

 

Flags: Run Last