Constraint

Object Hierarchy:

[ CCode ( type_id = "gtk_constraint_get_type ()" ) ]
public class Constraint : Object

Constraint describes a constraint between an attribute on a widget and another attribute on another widget, expressed as a linear equation like:

  target.attr1 = source.attr2 × multiplier + constant

Each Constraint is part of a system that will be solved by a ConstraintLayout in order to allocate and position each child widget.

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

Namespace: Gtk

Package: gtk4

public double constant { get; construct; }
The constant value to be added to the source_attribute.
public double multiplier { get; construct; }
The multiplication factor to be applied to the source_attribute.
public ConstraintRelation relation { get; construct; }
The order relation between the terms of the constraint.
public ConstraintTarget source { get; construct; }
The source of the constraint.
public ConstraintAttribute source_attribute { get; construct; }
The attribute of the source read by the constraint.
public int strength { get; construct; }
The strength of the constraint.
public ConstraintTarget target { get; construct; }
The target of the constraint.
public ConstraintAttribute target_attribute { get; construct; }
The attribute of the target set by the constraint.

public Constraint (ConstraintTarget? target, ConstraintAttribute target_attribute, ConstraintRelation relation, ConstraintTarget? source, ConstraintAttribute source_attribute, double multiplier, double constant, int strength)
Creates a new Constraint representing a relation between a layout attribute on a source and a layout attribute on a target.
public Constraint.const (ConstraintTarget? target, ConstraintAttribute target_attribute, ConstraintRelation relation, double constant, int strength)
Creates a new Constraint representing a relation between a layout attribute on a target and a constant value.

public double get_constant ()
Retrieves the constant factor added to the source attributes' value.
public double get_multiplier ()
Retrieves the multiplication factor applied to the source attribute's value.
public ConstraintRelation get_relation ()
The order relation between the terms of the this .
public unowned ConstraintTarget? get_source ()
Retrieves the ConstraintTarget used as the source for this.
public ConstraintAttribute get_source_attribute ()
Retrieves the attribute of the source to be read by the this.
public int get_strength ()
Retrieves the strength of the constraint.
public unowned ConstraintTarget? get_target ()
Retrieves the ConstraintTarget used as the target for this.
public ConstraintAttribute get_target_attribute ()
Retrieves the attribute of the target to be set by the this.
public bool is_attached ()
Checks whether the this is attached to a ConstraintLayout, and it is contributing to the layout.
public bool is_constant ()
Checks whether the this describes a relation between an attribute on the target and a constant value.
public bool is_required ()
Checks whether the this is a required relation for solving the constraint layout.

All known members inherited from class GLib.Object