Struct IMContext 

pub struct IMContext { /* private fields */ }

IMContext defines the interface for GTK+ input methods. An input method is used by GTK+ text input widgets like Entry to map from key events to Unicode character strings.

The default input method can be set programmatically via the gtk-im-module GtkSettings property. Alternatively, you may set the GTK_IM_MODULE environment variable as documented in [Running GTK+ Applications][gtk-running].

The Entry im-module and TextView im-module properties may also be used to set input methods for specific widget instances. For instance, a certain entry widget might be expected to contain certain characters which would be easier to input with a certain input method.

An input method may consume multiple key events in sequence and finally output the composed result. This is called preediting, and an input method may provide feedback about this process by displaying the intermediate composition states as preedit text. For instance, the default GTK+ input method implements the input of arbitrary Unicode code points by holding down the Control and Shift keys and then typing “U” followed by the hexadecimal digits of the code point. When releasing the Control and Shift keys, preediting ends and the character is inserted as text. Ctrl+Shift+u20AC for example results in the € sign.

Additional input methods can be made available for use by GTK+ widgets as loadable modules. An input method module is a small shared library which implements a subclass of IMContext or IMContextSimple and exports these four functions:

⚠️ The following code is in C ⚠️

void im_module_init(GTypeModule *module);

This function should register the GType of the IMContext subclass which implements the input method by means of g_type_module_register_type(). Note that g_type_register_static() cannot be used as the type needs to be registered dynamically.

⚠️ The following code is in C ⚠️

void im_module_exit(void);

Here goes any cleanup code your input method might require on module unload.

⚠️ The following code is in C ⚠️

void im_module_list(const GtkIMContextInfo ***contexts, int *n_contexts)
{
  *contexts = info_list;
  *n_contexts = G_N_ELEMENTS (info_list);
}

This function returns the list of input methods provided by the module. The example implementation above shows a common solution and simply returns a pointer to statically defined array of GtkIMContextInfo items for each provided input method.

⚠️ The following code is in C ⚠️

GtkIMContext * im_module_create(const gchar *context_id);

This function should return a pointer to a newly created instance of the IMContext subclass identified by context_id. The context ID is the same as specified in the GtkIMContextInfo array returned by im_module_list().

After a new loadable input method module has been installed on the system, the configuration file gtk.immodules needs to be regenerated by [gtk-query-immodules-3.0][gtk-query-immodules-3.0], in order for the new input method to become available to GTK+ applications.

This is an Abstract Base Class, you cannot instantiate it.

Properties

input-hints

Readable | Writeable

input-purpose

Readable | Writeable

Signals

commit

The ::commit signal is emitted when a complete input sequence has been entered by the user. This can be a single character immediately after a key press or the final result of preediting.

delete-surrounding

The ::delete-surrounding signal is emitted when the input method needs to delete all or part of the context surrounding the cursor.

preedit-changed

The ::preedit-changed signal is emitted whenever the preedit sequence currently being entered has changed. It is also emitted at the end of a preedit sequence, in which case IMContextExt::preedit_string() returns the empty string.

preedit-end

The ::preedit-end signal is emitted when a preediting sequence has been completed or canceled.

preedit-start

The ::preedit-start signal is emitted when a new preediting sequence starts.

retrieve-surrounding

The ::retrieve-surrounding signal is emitted when the input method requires the context surrounding the cursor. The callback should set the input method surrounding context by calling the IMContextExt::set_surrounding() method.

Implements

IMContextExt, glib::ObjectExt

Implementations

impl IMContext

pub const NONE: Option<&'static IMContext> = None

Trait Implementations

impl Clone for IMContext

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for IMContext

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for IMContext

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for IMContext

impl HasParamSpec for IMContext

type ParamSpec = ParamSpecObject

type SetValue = IMContext

Preferred value to be used as setter for the associated ParamSpec.

type BuilderFn = fn(&str) -> ParamSpecObjectBuilder<'_, IMContext>

fn param_spec_builder() -> Self::BuilderFn

impl Hash for IMContext

fn hash<H>(&self, state: &mut H)

where H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl IsA<IMContext> for IMContextSimple

impl IsA<IMContext> for IMMulticontext

impl Ord for IMContext

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl ParentClassIs for IMContext

type Parent = Object

impl<OT: ObjectType> PartialEq<OT> for IMContext

fn eq(&self, other: &OT) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl<OT: ObjectType> PartialOrd<OT> for IMContext

fn partial_cmp(&self, other: &OT) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StaticType for IMContext

fn static_type() -> Type

Returns the type identifier of Self.