Graphics.UI.Gtk.General.StyleContext

Rendering UI elements

Description

GtkStyleContext is an object that stores styling information affecting a widget defined by WidgetPath.

In order to construct the final style information, StyleContext queries information from all attached StyleProviders. Style providers can be either attached explicitly to the context through styleContextAddProvider, or to the screen through @styleContextAddProviderForScreen. The resulting style is a combination of all providers' information in priority order.

For GTK+ widgets, any StyleContext returned by widgetGetStyleContext will already have a WidgetPath, a Screen and RTL/LTR information set. The style context will be also updated automatically if any of these settings change on the widget.

If you are using the theming layer standalone, you will need to set a widget path and a screen yourself to the created style context through styleContextSetPath and styleContextSetScreen, as well as updating the context yourself using styleContextInvalidate whenever any of the conditions change, such as a change in the "gtk-theme-name" setting or a hierarchy change in the rendered widget.

Types

data StyleContext

Instances

Eq StyleContext

Ord StyleContext

GObjectClass StyleContext

StyleContextClass StyleContext

class GObjectClass o => StyleContextClass o

Instances

StyleContextClass StyleContext

castToStyleContext :: GObjectClass obj => obj -> StyleContext

gTypeStyleContext :: GType

toStyleContext :: StyleContextClass o => o -> StyleContext

Constructors

styleContextNew

Arguments

:: IO StyleContext

A newly created StyleContext

Creates a standalone StyleContext, this style context won't be attached to any widget, so you may want to call styleContextSetPath yourself.

Note : This function is only useful when using the theming layer separated from GTK+, if you are using StyleContext to theme Widgets, use widgetGetStyleContext in order to get a style context ready to theme the widget.

Methods

styleContextAddProvider

Arguments

:: (StyleContextClass context, StyleProviderClass provider)

=> context

context a StyleContext

-> provider

provider a StyleProvider

-> Int

priority : the priority of the style provider. The lower it is, the earlier it will be used in the style construction. Typically this will be in the range between 1 and 800

-> IO ()

Adds a style provider to context, to be used in style construction. Note that a style provider added by this function only affects the style of the widget to which context belongs. If you want to affect the style of all widgets, use styleContextAddProviderForScreen.

Note : If both priorities are the same, A StyleProvider added through this function takes precedence over another added through @styleContextAddProviderForScreen.

styleContextAddProviderForScreen

Arguments

:: (ScreenClass screen, StyleProviderClass provider)

=> screen

screen a Screen

-> provider

provider a StyleProvider

-> Int

priority : the priority of the style provider. The lower it is, the earlier it will be used in the style construction. Typically this will be in the range between 1 and 800

-> IO ()

Adds a global style provider to screen, which will be used in style construction for all StyleContexts under screen.

GTK+ uses this to make styling information from Settings available.

Note : If both priorities are the same, A StyleProvider added through styleContextAddProvider takes precedence over another added through this function.

styleContextAddClass :: (StyleContextClass context, GlibString string) => context -> string -> IO ()

Adds a style class to context , so posterior calls to gtk_style_context_get() or any of the gtk_render_*() functions will make use of this new class for styling.

In the CSS file format, a GtkEntry defining an “entry” class, would be matched by:

GtkEntry.entry { ... }

While any widget defining an “entry” class would be matched by:

.entry { ... }

styleContextRemoveClass :: (StyleContextClass context, GlibString string) => context -> string -> IO ()

Removes className from context.

styleContextHasClass :: (StyleContextClass context, GlibString string) => context -> string -> IO Bool

Returns True if context currently has defined the given class name

styleContextListClasses :: (StyleContextClass context, GlibString string) => context -> IO [string]

Returns the list of classes currently defined in context.