Struct gtk4::Constraint

impl Constraint

pub fn new(
 target: Option<&impl IsA<ConstraintTarget>>,
 target_attribute: ConstraintAttribute,
 relation: ConstraintRelation,
 source: Option<&impl IsA<ConstraintTarget>>,
 source_attribute: ConstraintAttribute,
 multiplier: f64,
 constant: f64,
 strength: i32
) -> Constraint

Creates a new constraint representing a relation between a layout attribute on a source and a layout attribute on a target.

`relation`

the relation equivalence between target_attribute and source_attribute

`multiplier`

a multiplication factor to be applied to source_attribute

`constant`

a constant factor to be added to source_attribute

pub fn new_constant(
 target: Option<&impl IsA<ConstraintTarget>>,
 target_attribute: ConstraintAttribute,
 relation: ConstraintRelation,
 constant: f64,
 strength: i32
) -> Constraint

Creates a new constraint representing a relation between a layout attribute on a target and a constant value.

`relation`

the relation equivalence between target_attribute and constant

`constant`

a constant factor to be set on target_attribute

pub fn builder() -> ConstraintBuilder

Creates a new builder-pattern struct instance to construct Constraint objects.

This method returns an instance of ConstraintBuilder which can be used to create Constraint objects.

pub fn constant(&self) -> f64

Retrieves the constant factor added to the source attributes’ value.

pub fn multiplier(&self) -> f64

Retrieves the multiplication factor applied to the source attribute’s value.

pub fn relation(&self) -> ConstraintRelation

The order relation between the terms of the constraint.

pub fn source(&self) -> Option<ConstraintTarget>

Retrieves the ConstraintTarget used as the source for the constraint.

If the source is set to NULL at creation, the constraint will use the widget using the ConstraintLayout as the source.

pub fn source_attribute(&self) -> ConstraintAttribute

Retrieves the attribute of the source to be read by the constraint.

pub fn strength(&self) -> i32

Retrieves the strength of the constraint.

pub fn target(&self) -> Option<ConstraintTarget>

Retrieves the ConstraintTarget used as the target for the constraint.

If the targe is set to NULL at creation, the constraint will use the widget using the ConstraintLayout as the target.

pub fn target_attribute(&self) -> ConstraintAttribute

Retrieves the attribute of the target to be set by the constraint.

pub fn is_attached(&self) -> bool

Checks whether the constraint is attached to a ConstraintLayout, and it is contributing to the layout.

Returns

TRUE if the constraint is attached

pub fn is_constant(&self) -> bool

Checks whether the constraint describes a relation between an attribute on the property::Constraint::target and a constant value.

Returns

TRUE if the constraint is a constant relation

pub fn is_required(&self) -> bool

Checks whether the constraint is a required relation for solving the constraint layout.

Trait Implementations§

impl Clone for Constraint

fn clone(&self) -> Self

Returns a copy of the value. Read more

1.0.0 · source§

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

Performs copy-assignment from source. Read more

impl Debug for Constraint

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

Formats the value using the given formatter. Read more

impl Default for Constraint

fn default() -> Self

Returns the “default value” for a type. Read more

impl Display for Constraint

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

Formats the value using the given formatter. Read more

impl Hash for Constraint

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

Feeds this value into the given Hasher. Read more

1.3.0 · source§

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

Feeds a slice of this type into the given Hasher. Read more

impl Ord for Constraint

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

This method returns an Ordering between self and other. Read more

1.21.0 · source§

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

Compares and returns the maximum of two values. Read more

1.21.0 · source§

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

Compares and returns the minimum of two values. Read more

1.50.0 · source§

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

Restrict a value to a certain interval. Read more

impl ParentClassIs for Constraint

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

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

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

1.0.0 · source§

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 Constraint

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

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

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

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

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

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

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

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

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

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

impl StaticType for Constraint

fn static_type() -> Type

Returns the type identifier of Self.

Auto Trait Implementations§

impl RefUnwindSafe for Constraint

impl UnwindSafe for Constraint

Blanket Implementations§

impl<T> Any for Twhere
T: 'static + ?Sized,

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more

impl<T> Borrow<T> for Twhere
T: ?Sized,

const: unstable · source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more

impl<T> BorrowMut<T> for Twhere
T: ?Sized,

const: unstable · source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more

impl<T> Cast for Twhere
T: ObjectType,

fn upcast<T>(self) -> Twhere
T: ObjectType,
Self: IsA<T>,

Upcasts an object to a superclass or interface T. Read more

fn upcast_ref<T>(&self) -> &Twhere
T: ObjectType,
Self: IsA<T>,

Upcasts an object to a reference of its superclass or interface T. Read more

fn downcast<T>(self) -> Result<T, Self>where
T: ObjectType,
Self: CanDowncast<T>,

Tries to downcast to a subclass or interface implementor T. Read more

fn downcast_ref<T>(&self) -> Option<&T>where
T: ObjectType,
Self: CanDowncast<T>,

Tries to downcast to a reference of its subclass or interface implementor T. Read more

fn dynamic_cast<T>(self) -> Result<T, Self>where
T: ObjectType,

Tries to cast to an object of type T. This handles upcasting, downcasting and casting between interface and interface implementors. All checks are performed at runtime, while downcast and upcast will do many checks at compile-time already. Read more

fn dynamic_cast_ref<T>(&self) -> Option<&T>where
T: ObjectType,

Tries to cast to reference to an object of type T. This handles upcasting, downcasting and casting between interface and interface implementors. All checks are performed at runtime, while downcast and upcast will do many checks at compile-time already. Read more

unsafe fn unsafe_cast<T>(self) -> Twhere
T: ObjectType,

Casts to T unconditionally. Read more

unsafe fn unsafe_cast_ref<T>(&self) -> &Twhere
T: ObjectType,

Casts to &T unconditionally. Read more

impl<T> From<T> for T

const: unstable · source§

fn from(t: T) -> T

Returns the argument unchanged.

impl<T, U> Into for Twhere
U: From<T>,

const: unstable · source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

impl IsSubclassableExt for Uwhere
U: IsClass + ParentClassIs,

fn parent_class_init<T>(class: &mut Class)where
T: ObjectSubclass,
::Parent: IsSubclassable<T>,

fn parent_instance_init<T>(instance: &mut InitializingObject<T>)where
T: ObjectSubclass,
::Parent: IsSubclassable<T>,

impl<T> ObjectExt for Twhere
T: ObjectType,

fn is(&self) -> boolwhere
U: StaticType,

Returns true if the object is an instance of (can be cast to) T.

fn type_(&self) -> Type

Returns the type of the object.

fn object_class(&self) -> &Class<Object>

Returns the ObjectClass of the object. Read more

fn class(&self) -> &Class<T>where
T: IsClass,

Returns the class of the object.

fn class_of(&self) -> Option<&Class>where
U: IsClass,

Returns the class of the object in the given type T. Read more

fn interface(&self) -> Option<InterfaceRef<'_, U>>where
U: IsInterface,

Returns the interface T of the object. Read more

fn set_property<V>(&self, property_name: &str, value: V)where
V: ToValue,

Sets the property property_name of the object to value value. Read more

fn set_property_from_value(&self, property_name: &str, value: &Value)

Sets the property property_name of the object to value value. Read more

fn set_properties(&self, property_values: &[(&str, &dyn ToValue)])

Sets multiple properties of the object at once. Read more

fn set_properties_from_value(&self, property_values: &[(&str, Value)])

Sets multiple properties of the object at once. Read more

fn property<V>(&self, property_name: &str) -> Vwhere
V: 'static + for<'b> FromValue<'b>,

Gets the property property_name of the object and cast it to the type V. Read more

fn property_value(&self, property_name: &str) -> Value

Gets the property property_name of the object. Read more

fn has_property(&self, property_name: &str, type_: Option<Type>) -> bool

Check if the object has a property property_name of the given type_. Read more

fn property_type(&self, property_name: &str) -> Option<Type>

Get the type of the property property_name of this object. Read more

fn find_property(&self, property_name: &str) -> Option<ParamSpec>

Get the ParamSpec of the property property_name of this object.

fn list_properties(&self) -> PtrSlice<ParamSpec>

Return all ParamSpec of the properties of this object.

fn freeze_notify(&self) -> PropertyNotificationFreezeGuard

Freeze all property notifications until the return guard object is dropped. Read more

unsafe fn set_qdata<QD>(&self, key: Quark, value: QD)where
QD: 'static,

Set arbitrary data on this object with the given key. Read more

unsafe fn qdata<QD>(&self, key: Quark) -> Option<NonNull<QD>>where
QD: 'static,

Return previously set arbitrary data of this object with the given key. Read more

unsafe fn steal_qdata<QD>(&self, key: Quark) -> Option<QD>where
QD: 'static,

Retrieve previously set arbitrary data of this object with the given key. Read more

unsafe fn set_data<QD>(&self, key: &str, value: QD)where
QD: 'static,

Set arbitrary data on this object with the given key. Read more

unsafe fn data<QD>(&self, key: &str) -> Option<NonNull<QD>>where
QD: 'static,

Return previously set arbitrary data of this object with the given key. Read more

unsafe fn steal_data<QD>(&self, key: &str) -> Option<QD>where
QD: 'static,

Retrieve previously set arbitrary data of this object with the given key. Read more

fn block_signal(&self, handler_id: &SignalHandlerId)

Block a given signal handler. Read more

fn unblock_signal(&self, handler_id: &SignalHandlerId)

Unblock a given signal handler.

fn stop_signal_emission(&self, signal_id: SignalId, detail: Option<Quark>)

Stop emission of the currently emitted signal.

fn stop_signal_emission_by_name(&self, signal_name: &str)

Stop emission of the currently emitted signal by the (possibly detailed) signal name.

fn connect<F>(
 &self,
 signal_name: &str,
 after: bool,
 callback: F
) -> SignalHandlerIdwhere
 F: 'static + Fn(&[Value]) -> Option<Value> + Send + Sync,

Connect to the signal signal_name on this object. Read more

fn connect_id<F>(
 &self,
 signal_id: SignalId,
 details: Option<Quark>,
 after: bool,
 callback: F
) -> SignalHandlerIdwhere
 F: 'static + Fn(&[Value]) -> Option<Value> + Send + Sync,

Connect to the signal signal_id on this object. Read more

fn connect_local<F>(
 &self,
 signal_name: &str,
 after: bool,
 callback: F
) -> SignalHandlerIdwhere
 F: 'static + Fn(&[Value]) -> Option<Value>,

Connect to the signal signal_name on this object. Read more

fn connect_local_id<F>(
 &self,
 signal_id: SignalId,
 details: Option<Quark>,
 after: bool,
 callback: F
) -> SignalHandlerIdwhere
 F: 'static + Fn(&[Value]) -> Option<Value>,

Connect to the signal signal_id on this object. Read more

unsafe fn connect_unsafe<F>(
 &self,
 signal_name: &str,
 after: bool,
 callback: F
) -> SignalHandlerIdwhere
 F: Fn(&[Value]) -> Option<Value>,

Connect to the signal signal_name on this object. Read more

unsafe fn connect_unsafe_id<F>(
 &self,
 signal_id: SignalId,
 details: Option<Quark>,
 after: bool,
 callback: F
) -> SignalHandlerIdwhere
 F: Fn(&[Value]) -> Option<Value>,

Connect to the signal signal_id on this object. Read more

fn connect_closure(
    &self,
    signal_name: &str,
    after: bool,
    closure: RustClosure
) -> SignalHandlerId

Connect a closure to the signal signal_name on this object. Read more

fn connect_closure_id(
 &self,
 signal_id: SignalId,
 details: Option<Quark>,
 after: bool,
 closure: RustClosure
) -> SignalHandlerId

Connect a closure to the signal signal_id on this object. Read more

fn watch_closure(&self, closure: &impl AsRef<Closure>)

Limits the lifetime of closure to the lifetime of the object. When the object’s reference count drops to zero, the closure will be invalidated. An invalidated closure will ignore any calls to invoke_with_values, or invoke when using Rust closures.

fn emit<R>(&self, signal_id: SignalId, args: &[&dyn ToValue]) -> Rwhere
R: TryFromClosureReturnValue,

Emit signal by signal id. Read more

fn emit_with_values(&self, signal_id: SignalId, args: &[Value]) -> Option<Value>

Same as Self::emit but takes Value for the arguments.

fn emit_by_name<R>(&self, signal_name: &str, args: &[&dyn ToValue]) -> Rwhere
R: TryFromClosureReturnValue,

Emit signal by its name. Read more

fn emit_by_name_with_values(
 &self,
 signal_name: &str,
 args: &[Value]
) -> Option<Value>

Emit signal by its name. Read more

fn emit_by_name_with_details<R>(
 &self,
 signal_name: &str,
 details: Quark,
 args: &[&dyn ToValue]
) -> Rwhere
 R: TryFromClosureReturnValue,

Emit signal by its name with details. Read more

fn emit_by_name_with_details_and_values(
 &self,
 signal_name: &str,
 details: Quark,
 args: &[Value]
) -> Option<Value>

Emit signal by its name with details. Read more

fn emit_with_details<R>(
 &self,
 signal_id: SignalId,
 details: Quark,
 args: &[&dyn ToValue]
) -> Rwhere
 R: TryFromClosureReturnValue,

Emit signal by signal id with details. Read more

fn emit_with_details_and_values(
 &self,
 signal_id: SignalId,
 details: Quark,
 args: &[Value]
) -> Option<Value>

Emit signal by signal id with details. Read more

fn disconnect(&self, handler_id: SignalHandlerId)

Disconnect a previously connected signal handler.

fn connect_notify<F>(&self, name: Option<&str>, f: F) -> SignalHandlerIdwhere
F: 'static + Fn(&T, &ParamSpec) + Send + Sync,

Connect to the notify signal of the object. Read more

fn connect_notify_local<F>(&self, name: Option<&str>, f: F) -> SignalHandlerIdwhere
F: 'static + Fn(&T, &ParamSpec),

Connect to the notify signal of the object. Read more

unsafe fn connect_notify_unsafe<F>(
 &self,
 name: Option<&str>,
 f: F
) -> SignalHandlerIdwhere
 F: Fn(&T, &ParamSpec),

Connect to the notify signal of the object. Read more

fn notify(&self, property_name: &str)

Notify that the given property has changed its value. Read more

fn notify_by_pspec(&self, pspec: &ParamSpec)

Notify that the given property has changed its value. Read more

fn downgrade(&self) -> WeakRef<T>

Downgrade this object to a weak reference.

fn add_weak_ref_notify<F>(&self, f: F) -> WeakRefNotify<T>where
F: 'static + FnOnce() + Send,

Add a callback to be notified when the Object is disposed.

fn add_weak_ref_notify_local<F>(&self, f: F) -> WeakRefNotify<T>where
F: 'static + FnOnce(),

Add a callback to be notified when the Object is disposed. Read more

fn bind_property<'f, 't, O, 'a>(
 &'a self,
 source_property: &'a str,
 target: &'a O,
 target_property: &'a str
) -> BindingBuilder<'a, 'f, 't>where
 O: ObjectType,

Bind property source_property on this object to the target_property on the target object. Read more

fn ref_count(&self) -> u32

Returns the strong reference count of this object.

unsafe fn run_dispose(&self)

Runs the dispose mechanism of the object. Read more

impl<T> StaticTypeExt for Twhere
T: StaticType,

fn ensure_type()

Ensures that the type has been registered with the type system.

type Owned = T

The resulting type after obtaining ownership.

fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more

fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more

impl<T> ToString for Twhere
T: Display + ?Sized,

default fn to_string(&self) -> String

Converts the given value to a String. Read more

impl<T, U> TryFrom for Twhere
U: Into<T>,

type Error = Infallible

The type returned in the event of a conversion error.

const: unstable · source§

fn try_from(value: U) -> Result<T, <T as TryFrom>::Error>

Performs the conversion.

impl<T> TryFromClosureReturnValue for Twhere
T: 'static + for<'a> FromValue<'a> + StaticType,

fn try_from_closure_return_value(v: Option<Value>) -> Result<T, BoolError>

impl<T, U> TryInto for Twhere
U: TryFrom<T>,

type Error = >::Error

The type returned in the event of a conversion error.

const: unstable · source§

fn try_into(self) -> Result<U, >::Error>

Performs the conversion.

impl<Super, Sub> CanDowncast for Superwhere
Super: IsA<Super>,
Sub: IsA<Super>,