Struct gio::PropertyAction

#[repr(transparent)]
pub struct PropertyAction { /* private fields */ }

A PropertyAction is a way to get a Action with a state value reflecting and controlling the value of a glib::Object property.

The state of the action will correspond to the value of the property. Changing it will change the property (assuming the requested value matches the requirements as specified in the GParamSpec).

Only the most common types are presently supported. Booleans are mapped to booleans, strings to strings, signed/unsigned integers to int32/uint32 and floats and doubles to doubles.

If the property is an enum then the state will be string-typed and conversion will automatically be performed between the enum value and “nick” string as per the GEnumValue table.

Flags types are not currently supported.

Properties of object types, boxed types and pointer types are not supported and probably never will be.

Properties of glib::Variant types are not currently supported.

If the property is boolean-valued then the action will have a NULL parameter type, and activating the action (with no parameter) will toggle the value of the property.

In all other cases, the parameter type will correspond to the type of the property.

The general idea here is to reduce the number of locations where a particular piece of state is kept (and therefore has to be synchronised between). PropertyAction does not have a separate state that is kept in sync with the property value – its state is the property value.

For example, it might be useful to create a Action corresponding to the “visible-child-name” property of a GtkStack so that the current page can be switched from a menu. The active radio indication in the menu is then directly determined from the active page of the GtkStack.

An anti-example would be binding the “active-id” property on a GtkComboBox. This is because the state of the combobox itself is probably uninteresting and is actually being used to control something else.

Another anti-example would be to bind to the “visible-child-name” property of a GtkStack if this value is actually stored in Settings. In that case, the real source of the value is Settings. If you want a Action to control a setting stored in Settings, see SettingsExt::create_action() instead, and possibly combine its use with SettingsExtManual::bind().

Implements

glib::ObjectExt, ActionExt

Implementations

impl PropertyAction

pub fn new( name: &str, object: &impl IsA<Object>, property_name: &str ) -> PropertyAction

Creates a Action corresponding to the value of property property_name on object.

The property must be existent and readable and writable (and not construct-only).

This function takes a reference on object and doesn’t release it until the action is destroyed.

name

the name of the action to create

object

the object that has the property to wrap

property_name

the name of the property

Returns

a new PropertyAction

pub fn inverts_boolean(&self) -> bool

If true, the state of the action will be the negation of the property value, provided the property is boolean.

Trait Implementations

impl Clone for PropertyAction

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for PropertyAction

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

Formats the value using the given formatter.

impl Display for PropertyAction

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

Formats the value using the given formatter.

impl Hash for PropertyAction

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 Ord for PropertyAction

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

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl ParentClassIs for PropertyAction

type Parent = Object

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

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

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

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

This method tests less than (for self and other) and is used by the < operator.

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

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

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

This method tests greater than (for self and other) and is used by the > operator.

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

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

impl StaticType for PropertyAction

fn static_type() -> Type

Returns the type identifier of Self.

impl Eq for PropertyAction

impl IsA<Action> for PropertyAction