GI.Gtk.Objects.Builder

A GtkBuilder reads XML descriptions of a user interface and instantiates the described objects.

To create a GtkBuilder from a user interface description, call builderNewFromFile, builderNewFromResource or builderNewFromString.

In the (unusual) case that you want to add user interface descriptions from multiple sources to the same GtkBuilder you can call builderNew to get an empty builder and populate it by (multiple) calls to builderAddFromFile, builderAddFromResource or builderAddFromString.

A GtkBuilder holds a reference to all objects that it has constructed and drops these references when it is finalized. This finalization can cause the destruction of non-widget objects or widgets which are not contained in a toplevel window. For toplevel windows constructed by a builder, it is the responsibility of the user to call windowDestroy to get rid of them and all the widgets they contain.

The functions builderGetObject and builderGetObjects can be used to access the widgets in the interface by the names assigned to them inside the UI description. Toplevel windows returned by these functions will stay around until the user explicitly destroys them with windowDestroy. Other widgets will either be part of a larger hierarchy constructed by the builder (in which case you should not have to worry about their lifecycle), or without a parent, in which case they have to be added to some container to make use of them. Non-widget objects need to be reffed with objectRef to keep them beyond the lifespan of the builder.

GtkBuilder UI Definitions

GtkBuilder parses textual descriptions of user interfaces which are specified in XML format. We refer to these descriptions as “GtkBuilder UI definitions” or just “UI definitions” if the context is clear.

The toplevel element is <interface>. It optionally takes a “domain” attribute, which will make the builder look for translated strings using dgettext() in the domain specified. This can also be done by calling builderSetTranslationDomain on the builder.

Objects are described by <object> elements, which can contain <property> elements to set properties, <signal> elements which connect signals to handlers, and <child> elements, which describe child objects (most often widgets inside a container, but also e.g. actions in an action group, or columns in a tree model). A <child> element contains an <object> element which describes the child object.

The target toolkit version(s) are described by <requires> elements, the “lib” attribute specifies the widget library in question (currently the only supported value is “gtk”) and the “version” attribute specifies the target version in the form “<major>.<minor>”. GtkBuilder will error out if the version requirements are not met.

Typically, the specific kind of object represented by an <object> element is specified by the “class” attribute. If the type has not been loaded yet, GTK tries to find the get_type() function from the class name by applying heuristics. This works in most cases, but if necessary, it is possible to specify the name of the get_type() function explicitly with the "type-func" attribute.

Objects may be given a name with the “id” attribute, which allows the application to retrieve them from the builder with builderGetObject. An id is also necessary to use the object as property value in other parts of the UI definition. GTK reserves ids starting and ending with ___ (three consecutive underscores) for its own purposes.

Setting properties of objects is pretty straightforward with the <property> element: the “name” attribute specifies the name of the property, and the content of the element specifies the value. If the “translatable” attribute is set to a true value, GTK uses gettext() (or dgettext() if the builder has a translation domain set) to find a translation for the value. This happens before the value is parsed, so it can be used for properties of any type, but it is probably most useful for string properties. It is also possible to specify a context to disambiguate short strings, and comments which may help the translators.

GtkBuilder can parse textual representations for the most common property types: characters, strings, integers, floating-point numbers, booleans (strings like “TRUE”, “t”, “yes”, “y”, “1” are interpreted as True, strings like “FALSE”, “f”, “no”, “n”, “0” are interpreted as False), enumerations (can be specified by their name, nick or integer value), flags (can be specified by their name, nick, integer value, optionally combined with “|”, e.g. “GTK_INPUT_HINT_EMOJI|GTK_INPUT_HINT_LOWERCASE”) and colors (in a format understood by rGBAParse).

GVariants can be specified in the format understood by variantParse, and pixbufs can be specified as a filename of an image file to load.

Objects can be referred to by their name and by default refer to objects declared in the local XML fragment and objects exposed via builderExposeObject. In general, GtkBuilder allows forward references to objects — declared in the local XML; an object doesn’t have to be constructed before it can be referred to. The exception to this rule is that an object has to be constructed before it can be used as the value of a construct-only property.

It is also possible to bind a property value to another object's property value using the attributes "bind-source" to specify the source object of the binding, and optionally, "bind-property" and "bind-flags" to specify the source property and source binding flags respectively. Internally, GtkBuilder implements this using GBinding objects. For more information see objectBindProperty.

Sometimes it is necessary to refer to widgets which have implicitly been constructed by GTK as part of a composite widget, to set properties on them or to add further children (e.g. the content area of a GtkDialog). This can be achieved by setting the “internal-child” property of the <child> element to a true value. Note that GtkBuilder still requires an <object> element for the internal child, even if it has already been constructed.

A number of widgets have different places where a child can be added (e.g. tabs vs. page content in notebooks). This can be reflected in a UI definition by specifying the “type” attribute on a <child> The possible values for the “type” attribute are described in the sections describing the widget-specific portions of UI definitions.

Signal handlers and function pointers

Signal handlers are set up with the <signal> element. The “name” attribute specifies the name of the signal, and the “handler” attribute specifies the function to connect to the signal. The remaining attributes, “after”, “swapped” and “object”, have the same meaning as the corresponding parameters of the g_signal_connect_object() or g_signal_connect_data() functions. A “last_modification_time” attribute is also allowed, but it does not have a meaning to the builder.

If you rely on GModule support to lookup callbacks in the symbol table, the following details should be noted:

When compiling applications for Windows, you must declare signal callbacks with G_MODULE_EXPORT, or they will not be put in the symbol table. On Linux and Unix, this is not necessary; applications should instead be compiled with the -Wl,--export-dynamic CFLAGS, and linked against gmodule-export-2.0.

A GtkBuilder UI Definition

xml code

<interface>
  <object class="GtkDialog" id="dialog1">
    <child internal-child="content_area">
      <object class="GtkBox" id="vbox1">
        <child internal-child="action_area">
          <object class="GtkBox" id="hbuttonbox1">
            <child>
              <object class="GtkButton" id="ok_button">
                <property name="label" translatable="yes">_Ok</property>
                <property name="use-underline">True</property>
                <signal name="clicked" handler="ok_button_clicked"/>
              </object>
            </child>
          </object>
        </child>
      </object>
    </child>
  </object>
</interface>

Beyond this general structure, several object classes define their own XML DTD fragments for filling in the ANY placeholders in the DTD above. Note that a custom element in a <child> element gets parsed by the custom tag handler of the parent object, while a custom element in an <object> element gets parsed by the custom tag handler of the object.

These XML fragments are explained in the documentation of the respective objects.

A <template> tag can be used to define a widget class’s components. See the GtkWidget documentation for details.

Exported types

newtype Builder

Memory-managed wrapper type.

Constructors

Builder (ManagedPtr Builder)

Instances

Eq Builder

Defined in GI.Gtk.Objects.Builder

Methods

(==) :: Builder -> Builder -> Bool

(/=) :: Builder -> Builder -> Bool

GObject Builder

Defined in GI.Gtk.Objects.Builder

ManagedPtrNewtype Builder

Defined in GI.Gtk.Objects.Builder

Methods

toManagedPtr :: Builder -> ManagedPtr Builder

TypedObject Builder

Defined in GI.Gtk.Objects.Builder

Methods

glibType :: IO GType

HasParentTypes Builder

Defined in GI.Gtk.Objects.Builder

IsGValue (Maybe Builder)

Convert Builder to and from GValue. See toGValue and fromGValue.

Defined in GI.Gtk.Objects.Builder

Methods

gvalueGType_ :: IO GType

gvalueSet_ :: Ptr GValue -> Maybe Builder -> IO ()

gvalueGet_ :: Ptr GValue -> IO (Maybe Builder)

type ParentTypes Builder

Defined in GI.Gtk.Objects.Builder

type ParentTypes Builder = '[Object]

class (GObject o, IsDescendantOf Builder o) => IsBuilder o

Type class for types which can be safely cast to Builder, for instance with toBuilder.

Instances

(GObject o, IsDescendantOf Builder o) => IsBuilder o

Defined in GI.Gtk.Objects.Builder

toBuilder :: (MonadIO m, IsBuilder o) => o -> m Builder

Cast to Builder, for types for which this is known to be safe. For general casts, use castTo.

Methods

Click to display all available methods, including inherited ones

Methods

addFromFile, addFromResource, addFromString, addObjectsFromFile, addObjectsFromResource, addObjectsFromString, bindProperty, bindPropertyFull, createClosure, exposeObject, extendWithTemplate, forceFloating, freezeNotify, getv, isFloating, notify, notifyByPspec, ref, refSink, runDispose, stealData, stealQdata, thawNotify, unref, valueFromString, valueFromStringType, watchClosure.

Getters

getCurrentObject, getData, getObject, getObjects, getProperty, getQdata, getScope, getTranslationDomain, getTypeFromName.

Setters

setCurrentObject, setData, setDataFull, setProperty, setScope, setTranslationDomain.

addFromFile

builderAddFromFile

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> [Char]

filename: the name of the file to parse

-> m ()

(Can throw GError)

Parses a file containing a UI definition and merges it with the current contents of builder.

This function is useful if you need to call builderSetCurrentObject) to add user data to callbacks before loading GtkBuilder UI. Otherwise, you probably want builderNewFromFile instead.

If an error occurs, 0 will be returned and error will be assigned a GError from the GTK_BUILDER_ERROR, G_MARKUP_ERROR or G_FILE_ERROR domains.

It’s not really reasonable to attempt to handle failures of this call. You should not use this function with untrusted files (ie: files that are not part of your application). Broken GtkBuilder files can easily crash your program, and it’s possible that memory was leaked leading up to the reported failure. The only reasonable thing to do when an error is detected is to call g_error().

addFromResource

builderAddFromResource

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> Text

resourcePath: the path of the resource file to parse

-> m ()

(Can throw GError)

Parses a resource file containing a UI definition and merges it with the current contents of builder.

This function is useful if you need to call builderSetCurrentObject to add user data to callbacks before loading GtkBuilder UI. Otherwise, you probably want builderNewFromResource instead.

If an error occurs, 0 will be returned and error will be assigned a GError from the GTK_BUILDER_ERROR, G_MARKUP_ERROR or G_RESOURCE_ERROR domain.

It’s not really reasonable to attempt to handle failures of this call. The only reasonable thing to do when an error is detected is to call g_error().

addFromString

builderAddFromString

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> Text

buffer: the string to parse

-> Int64

length: the length of buffer (may be -1 if buffer is nul-terminated)

-> m ()

(Can throw GError)

Parses a string containing a UI definition and merges it with the current contents of builder.

This function is useful if you need to call builderSetCurrentObject to add user data to callbacks before loading GtkBuilder UI. Otherwise, you probably want builderNewFromString instead.

Upon errors False will be returned and error will be assigned a GError from the GTK_BUILDER_ERROR, G_MARKUP_ERROR or G_VARIANT_PARSE_ERROR domain.

It’s not really reasonable to attempt to handle failures of this call. The only reasonable thing to do when an error is detected is to call g_error().

addObjectsFromFile

builderAddObjectsFromFile

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> [Char]

filename: the name of the file to parse

-> [Text]

objectIds: nul-terminated array of objects to build

-> m ()

(Can throw GError)

Parses a file containing a UI definition building only the requested objects and merges them with the current contents of builder.

Upon errors, 0 will be returned and error will be assigned a GError from the GTK_BUILDER_ERROR, G_MARKUP_ERROR or G_FILE_ERROR domain.

If you are adding an object that depends on an object that is not its child (for instance a GtkTreeView that depends on its GtkTreeModel), you have to explicitly list all of them in objectIds.

addObjectsFromResource

builderAddObjectsFromResource

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> Text

resourcePath: the path of the resource file to parse

-> [Text]

objectIds: nul-terminated array of objects to build

-> m ()

(Can throw GError)

Parses a resource file containing a UI definition, building only the requested objects and merges them with the current contents of builder.

Upon errors, 0 will be returned and error will be assigned a GError from the GTK_BUILDER_ERROR, G_MARKUP_ERROR or G_RESOURCE_ERROR domain.

If you are adding an object that depends on an object that is not its child (for instance a GtkTreeView that depends on its GtkTreeModel), you have to explicitly list all of them in objectIds.

addObjectsFromString

builderAddObjectsFromString

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> Text

buffer: the string to parse

-> Int64

length: the length of buffer (may be -1 if buffer is nul-terminated)

-> [Text]

objectIds: nul-terminated array of objects to build

-> m ()

(Can throw GError)

Parses a string containing a UI definition, building only the requested objects and merges them with the current contents of builder.

Upon errors False will be returned and error will be assigned a GError from the GTK_BUILDER_ERROR or G_MARKUP_ERROR domain.

If you are adding an object that depends on an object that is not its child (for instance a GtkTreeView that depends on its GtkTreeModel), you have to explicitly list all of them in objectIds.

createClosure

builderCreateClosure

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a, IsObject b)

=> a

builder: a GtkBuilder

-> Text

functionName: name of the function to look up

-> [BuilderClosureFlags]

flags: closure creation flags

-> Maybe b

object: Object to create the closure with

-> m (Maybe (GClosure c))

Returns: A new closure for invoking functionName (Can throw GError)

Creates a closure to invoke the function called functionName.

This is using the create_closure() implementation of builder's BuilderScope.

If no closure could be created, Nothing will be returned and error will be set.

exposeObject

builderExposeObject

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a, IsObject b)

=> a

builder: a GtkBuilder

-> Text

name: the name of the object exposed to the builder

-> b

object: the object to expose

-> m ()

Add object to the builder object pool so it can be referenced just like any other object built by builder.

Only a single object may be added using name. However, it is not an error to expose the same object under multiple names. gtk_builder_get_object() may be used to determine if an object has already been added with name.

extendWithTemplate

builderExtendWithTemplate

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a, IsObject b)

=> a

builder: a GtkBuilder

-> b

object: the object that is being extended

-> GType

templateType: the type that the template is for

-> Text

buffer: the string to parse

-> Int64

length: the length of buffer (may be -1 if buffer is nul-terminated)

-> m ()

(Can throw GError)

Main private entry point for building composite components from template XML.

Most likely you do not need to call this function in applications as templates are handled by GtkWidget.

getCurrentObject

builderGetCurrentObject

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> m (Maybe Object)

Returns: the current object

Gets the current object set via builderSetCurrentObject.

getObject

builderGetObject

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> Text

name: name of object to get

-> m (Maybe Object)

Returns: the object named name

Gets the object named name.

Note that this function does not increment the reference count of the returned object.

getObjects

builderGetObjects

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> m [Object]

Returns: a newly-allocated GSList containing all the objects constructed by the GtkBuilder instance. It should be freed by g_slist_free()

Gets all objects that have been constructed by builder.

Note that this function does not increment the reference counts of the returned objects.

getScope

builderGetScope

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> m BuilderScope

Returns: the current scope

Gets the scope in use that was set via builderSetScope.

getTranslationDomain

builderGetTranslationDomain

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> m (Maybe Text)

Returns: the translation domain

Gets the translation domain of builder.

getTypeFromName

builderGetTypeFromName

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> Text

typeName: type name to lookup

-> m GType

Returns: the GType found for typeName or G_TYPE_INVALID if no type was found

Looks up a type by name.

This is using the virtual function that GtkBuilder has for that purpose. This is mainly used when implementing the GtkBuildable interface on a type.

new

builderNew

Arguments

:: (HasCallStack, MonadIO m)

=> m Builder

Returns: a new (empty) GtkBuilder object

Creates a new empty builder object.

This function is only useful if you intend to make multiple calls to builderAddFromFile, builderAddFromResource or builderAddFromString in order to merge multiple UI descriptions into a single builder.

newFromFile

builderNewFromFile

Arguments

:: (HasCallStack, MonadIO m)

=> [Char]

filename: filename of user interface description file

-> m Builder

Returns: a GtkBuilder containing the described interface

Parses the UI definition in the file filename.

If there is an error opening the file or parsing the description then the program will be aborted. You should only ever attempt to parse user interface descriptions that are shipped as part of your program.

newFromResource

builderNewFromResource

Arguments

:: (HasCallStack, MonadIO m)

=> Text

resourcePath: a GResource resource path

-> m Builder

Returns: a GtkBuilder containing the described interface

Parses the UI definition at resourcePath.

If there is an error locating the resource or parsing the description, then the program will be aborted.

newFromString

builderNewFromString

Arguments

:: (HasCallStack, MonadIO m)

=> Text

string: a user interface (XML) description

-> Int64

length: the length of string, or -1

-> m Builder

Returns: a GtkBuilder containing the interface described by string

Parses the UI definition in string.

If string is Nothing-terminated, then length should be -1. If length is not -1, then it is the length of string.

If there is an error parsing string then the program will be aborted. You should not attempt to parse user interface description from untrusted sources.

setCurrentObject

builderSetCurrentObject

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a, IsObject b)

=> a

builder: a GtkBuilder

-> Maybe b

currentObject: the new current object

-> m ()

Sets the current object for the builder.

The current object can be thought of as the this object that the builder is working for and will often be used as the default object when an object is optional.

widgetInitTemplate for example will set the current object to the widget the template is inited for. For functions like builderNewFromResource, the current object will be Nothing.

setScope

builderSetScope

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a, IsBuilderScope b)

=> a

builder: a GtkBuilder

-> Maybe b

scope: the scope to use

-> m ()

Sets the scope the builder should operate in.

If scope is Nothing, a new BuilderCScope will be created.

setTranslationDomain

builderSetTranslationDomain

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> Maybe Text

domain: the translation domain

-> m ()

Sets the translation domain of builder.

valueFromString

builderValueFromString

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> GParamSpec

pspec: the GParamSpec for the property

-> Text

string: the string representation of the value

-> m GValue

(Can throw GError)

Demarshals a value from a string.

This function calls valueInit on the value argument, so it need not be initialised beforehand.

Can handle char, uchar, boolean, int, uint, long, ulong, enum, flags, float, double, string, GdkRGBA and GtkAdjustment type values.

Upon errors False will be returned and error will be assigned a GError from the GTK_BUILDER_ERROR domain.

valueFromStringType

builderValueFromStringType

Arguments

:: (HasCallStack, MonadIO m, IsBuilder a)

=> a

builder: a GtkBuilder

-> GType

type: the GType of the value

-> Text

string: the string representation of the value

-> m GValue

(Can throw GError)

Demarshals a value from a string.

Unlike builderValueFromString, this function takes a GType instead of GParamSpec.

Calls valueInit on the value argument, so it need not be initialised beforehand.

Upon errors False will be returned and error will be assigned a GError from the GTK_BUILDER_ERROR domain.

Properties

currentObject

The object the builder is evaluating for.

clearBuilderCurrentObject :: (MonadIO m, IsBuilder o) => o -> m ()

Set the value of the “current-object” property to Nothing. When overloading is enabled, this is equivalent to

clear #currentObject

constructBuilderCurrentObject :: (IsBuilder o, MonadIO m, IsObject a) => a -> m (GValueConstruct o)

Construct a GValueConstruct with valid value for the “current-object” property. This is rarely needed directly, but it is used by new.

getBuilderCurrentObject :: (MonadIO m, IsBuilder o) => o -> m (Maybe Object)

Get the value of the “current-object” property. When overloading is enabled, this is equivalent to

get builder #currentObject

setBuilderCurrentObject :: (MonadIO m, IsBuilder o, IsObject a) => o -> a -> m ()

Set the value of the “current-object” property. When overloading is enabled, this is equivalent to

set builder [ #currentObject := value ]

scope

The scope the builder is operating in

clearBuilderScope :: (MonadIO m, IsBuilder o) => o -> m ()

Set the value of the “scope” property to Nothing. When overloading is enabled, this is equivalent to

clear #scope

constructBuilderScope :: (IsBuilder o, MonadIO m, IsBuilderScope a) => a -> m (GValueConstruct o)

Construct a GValueConstruct with valid value for the “scope” property. This is rarely needed directly, but it is used by new.

getBuilderScope :: (MonadIO m, IsBuilder o) => o -> m BuilderScope

Get the value of the “scope” property. When overloading is enabled, this is equivalent to

get builder #scope

setBuilderScope :: (MonadIO m, IsBuilder o, IsBuilderScope a) => o -> a -> m ()

Set the value of the “scope” property. When overloading is enabled, this is equivalent to

set builder [ #scope := value ]

translationDomain

The translation domain used when translating property values that have been marked as translatable.

If the translation domain is Nothing, GtkBuilder uses gettext(), otherwise dgettext.

clearBuilderTranslationDomain :: (MonadIO m, IsBuilder o) => o -> m ()

Set the value of the “translation-domain” property to Nothing. When overloading is enabled, this is equivalent to

clear #translationDomain

constructBuilderTranslationDomain :: (IsBuilder o, MonadIO m) => Text -> m (GValueConstruct o)

Construct a GValueConstruct with valid value for the “translation-domain” property. This is rarely needed directly, but it is used by new.

getBuilderTranslationDomain :: (MonadIO m, IsBuilder o) => o -> m (Maybe Text)

Get the value of the “translation-domain” property. When overloading is enabled, this is equivalent to

get builder #translationDomain

setBuilderTranslationDomain :: (MonadIO m, IsBuilder o) => o -> Text -> m ()

Set the value of the “translation-domain” property. When overloading is enabled, this is equivalent to

set builder [ #translationDomain := value ]