gtk4/org.gtkkn.bindings.gtk/Constraint

Constraint

open class Constraint(pointer: <Error class: unknown class><<Error class: unknown class>>)

GtkConstraint describes a constraint between attributes of two widgets, expressed as a linear equation.

The typical equation for a constraint is:

target.target_attr = source.source_attr × multiplier + constant

Each GtkConstraint is part of a system that will be solved by a class@Gtk.ConstraintLayout in order to allocate and position each child widget or guide.

The source and target, as well as their attributes, of a GtkConstraint instance are immutable after creation.

Constructors

Constraint

constructor(target: ConstraintTarget? = null, targetAttribute: ConstraintAttribute, relation: ConstraintRelation, source: ConstraintTarget? = null, sourceAttribute: ConstraintAttribute, multiplier: Double, constant: Double, strength: Int)

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

constructor(target: ConstraintTarget? = null, targetAttribute: ConstraintAttribute, relation: ConstraintRelation, constant: Double, strength: Int)

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

constructor(pointer: <Error class: unknown class><<Error class: unknown class>>)

Types

Companion

object Companion

Properties

constant

open val constant: Double

The constant value to be added to the property@Gtk.Constraint:source-attribute.

gtkConstraintPointer

val gtkConstraintPointer: <Error class: unknown class><<Error class: unknown class>>

multiplier

open val multiplier: Double

The multiplication factor to be applied to the property@Gtk.Constraint:source-attribute.

relation

open val relation: ConstraintRelation

The order relation between the terms of the constraint.

source

open val source: ConstraintTarget?

The source of the constraint.

sourceAttribute

open val sourceAttribute: ConstraintAttribute

The attribute of the property@Gtk.Constraint:source read by the constraint.

strength

open val strength: Int

The strength of the constraint.

target

open val target: ConstraintTarget?

The target of the constraint.

targetAttribute

open val targetAttribute: ConstraintAttribute

The attribute of the property@Gtk.Constraint:target set by the constraint.

Functions

getConstant

open fun getConstant(): Double

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

getMultiplier

open fun getMultiplier(): Double

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

getRelation

open fun getRelation(): ConstraintRelation

The order relation between the terms of the constraint.

getSource

open fun getSource(): ConstraintTarget?

Retrieves the iface@Gtk.ConstraintTarget used as the source for the constraint.

getSourceAttribute

open fun getSourceAttribute(): ConstraintAttribute

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

getStrength

open fun getStrength(): Int

Retrieves the strength of the constraint.

getTarget

open fun getTarget(): ConstraintTarget?

Retrieves the iface@Gtk.ConstraintTarget used as the target for the constraint.

getTargetAttribute

open fun getTargetAttribute(): ConstraintAttribute

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

isAttached

open fun isAttached(): Boolean

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

isConstant

open fun isConstant(): Boolean

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

isRequired

open fun isRequired(): Boolean

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