Struct ConstraintLayout 

pub struct ConstraintLayout { /* private fields */ }

=150@required, ==250@medium)]

Finally, it's also possible to use simple arithmetic operators:

// width of button1 must be equal to width of button2 // divided by 2 plus 12 [button1(button2 / 2 + 12)]

# Implements

[`LayoutManagerExt`][trait@crate::prelude::LayoutManagerExt], [`trait@glib::ObjectExt`], [`BuildableExt`][trait@crate::prelude::BuildableExt]

GLib type: GObject with reference counted clone semantics.

Implementations

impl ConstraintLayout

pub fn new() -> ConstraintLayout

Creates a new ConstraintLayout layout manager.

Returns

the newly created ConstraintLayout

pub fn add_constraint(&self, constraint: Constraint)

Adds a constraint to the layout manager.

The source and target properties of constraint can be:

• set to NULL to indicate that the constraint refers to the widget using layout
• set to the Widget using layout
• set to a child of the Widget using layout
• set to a ConstraintGuide that is part of layout

The @self acquires the ownership of @constraint after calling this function.

constraint

a Constraint

pub fn add_guide(&self, guide: ConstraintGuide)

Adds a guide to layout.

A guide can be used as the source or target of constraints, like a widget, but it is not visible.

The layout acquires the ownership of guide after calling this function.

guide

a ConstraintGuide object

pub fn observe_constraints(&self) -> ListModel

Returns a GListModel to track the constraints that are part of the layout.

Calling this function will enable extra internal bookkeeping to track constraints and emit signals on the returned listmodel. It may slow down operations a lot.

Applications should try hard to avoid calling this function because of the slowdowns.

Returns

a GListModel tracking the layout’s constraints

pub fn observe_guides(&self) -> ListModel

Returns a GListModel to track the guides that are part of the layout.

Calling this function will enable extra internal bookkeeping to track guides and emit signals on the returned listmodel. It may slow down operations a lot.

Applications should try hard to avoid calling this function because of the slowdowns.

Returns

a GListModel tracking the layout’s guides

pub fn remove_all_constraints(&self)

Removes all constraints from the layout manager.

pub fn remove_constraint(&self, constraint: &Constraint)

Removes constraint from the layout manager, so that it no longer influences the layout.

constraint

a Constraint

pub fn remove_guide(&self, guide: &ConstraintGuide)

Removes guide from the layout manager, so that it no longer influences the layout.

guide

a ConstraintGuide object

impl ConstraintLayout

pub fn add_constraints_from_description<'a, W: IsA<Widget>>( &self, lines: impl IntoStrV, hspacing: i32, vspacing: i32, views: impl IntoIterator<Item = (&'a str, &'a W)>, ) -> Result<Vec<Constraint>, Error>

=20)]-|

// Operators [button1(button2 / 3 + 50)]

// Named attributes [button1(==button2.height)]

## `lines`
an array of Visual Format Language lines
  defining a set of constraints
## `hspacing`
default horizontal spacing value, or -1 for the fallback value
## `vspacing`
default vertical spacing value, or -1 for the fallback value
## `views`
a dictionary of `[ name, target ]`
  pairs; the `name` keys map to the view names in the VFL lines, while
  the `target` values map to children of the widget using a [`ConstraintLayout`][crate::ConstraintLayout],
  or guides

# Returns

the list of
  [`Constraint`][crate::Constraint] instances that were added to the layout

Trait Implementations

impl Clone for ConstraintLayout

fn clone(&self) -> Self

Makes a clone of this shared reference.

This increments the strong reference count of the object. Dropping the object will decrement it again.

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

Performs copy-assignment from source.

impl Debug for ConstraintLayout

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

Formats the value using the given formatter.

impl Default for ConstraintLayout

fn default() -> Self

Returns the “default value” for a type.

impl Eq for ConstraintLayout

impl HasParamSpec for ConstraintLayout

type ParamSpec = ParamSpecObject

type SetValue = ConstraintLayout

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

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

fn param_spec_builder() -> Self::BuilderFn

impl Hash for ConstraintLayout

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

where H: Hasher,

Hashes the memory address of this object.

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<Buildable> for ConstraintLayout

impl IsA<LayoutManager> for ConstraintLayout

impl Ord for ConstraintLayout

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

Comparison for two GObjects.

Compares the memory addresses of the provided objects.

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 ConstraintLayout

type Parent = LayoutManager

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

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

Equality for two GObjects.

Two GObjects are equal if their memory addresses are equal.

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

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

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

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

Partial comparison for two GObjects.

Compares the memory addresses of the provided objects.

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 ConstraintLayout

fn static_type() -> Type

Returns the type identifier of Self.