Gtk.Constraint – gtk4 – Vala Binding Reference

Description:

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

`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 [[email protected]] 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.

Namespace: Gtk

Package: gtk4

Content:

Properties:

public double constant { get; construct; }

The constant value to be added to the [property@Gtk.

public double multiplier { get; construct; }

The multiplication factor to be applied to the [property@Gtk.

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 [property@Gtk.

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 [property@Gtk.

Creation methods:

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.

Methods:

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 constraint.

public unowned ConstraintTarget? get_source ()

Retrieves the [iface@Gtk.

public ConstraintAttribute get_source_attribute ()

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

public int get_strength ()

Retrieves the strength of the constraint.

public unowned ConstraintTarget? get_target ()

Retrieves the [iface@Gtk.

public ConstraintAttribute get_target_attribute ()

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

public bool is_attached ()

Checks whether the constraint is attached to a [class@Gtk.

public bool is_constant ()

Checks whether the constraint describes a relation between an attribute on the [property@Gtk.

public bool is_required ()

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

Inherited Members:

All known members inherited from class GLib.Object

@get
@new
@ref
@set
add_toggle_ref
add_weak_pointer
bind_property
connect
constructed
disconnect
dispose
dup_data
dup_qdata
force_floating
freeze_notify
get_class
get_data

get_property
get_qdata
get_type
getv
interface_find_property
interface_install_property
interface_list_properties
is_floating
new_valist
new_with_properties
newv
notify
notify_property
ref_count
ref_sink
remove_toggle_ref
remove_weak_pointer

replace_data
replace_qdata
set_data
set_data_full
set_property
set_qdata
set_qdata_full
set_valist
setv
steal_data
steal_qdata
thaw_notify
unref
watch_closure
weak_ref
weak_unref