#[repr(transparent)]
pub struct SizeGroup { /* private fields */ }
Expand description

SizeGroup provides a mechanism for grouping a number of widgets together so they all request the same amount of space. This is typically useful when you want a column of widgets to have the same size, but you can’t use a Grid widget.

In detail, the size requested for each widget in a SizeGroup is the maximum of the sizes that would have been requested for each widget in the size group if they were not in the size group. The mode of the size group (see SizeGroupExt::set_mode()) determines whether this applies to the horizontal size, the vertical size, or both sizes.

Note that size groups only affect the amount of space requested, not the size that the widgets finally receive. If you want the widgets in a SizeGroup to actually be the same size, you need to pack them in such a way that they get the size they request and not more. For example, if you are packing your widgets into a table, you would not include the GTK_FILL flag.

SizeGroup objects are referenced by each widget in the size group, so once you have added all widgets to a SizeGroup, you can drop the initial reference to the size group with g_object_unref(). If the widgets in the size group are subsequently destroyed, then they will be removed from the size group and drop their references on the size group; when all widgets have been removed, the size group will be freed.

Widgets can be part of multiple size groups; GTK+ will compute the horizontal size of a widget from the horizontal requisition of all widgets that can be reached from the widget by a chain of size groups of type SizeGroupMode::Horizontal or SizeGroupMode::Both, and the vertical size from the vertical requisition of all widgets that can be reached from the widget by a chain of size groups of type SizeGroupMode::Vertical or SizeGroupMode::Both.

Note that only non-contextual sizes of every widget are ever consulted by size groups (since size groups have no knowledge of what size a widget will be allocated in one dimension, it cannot derive how much height a widget will receive for a given width). When grouping widgets that trade height for width in mode SizeGroupMode::Vertical or SizeGroupMode::Both: the height for the minimum width will be the requested height for all widgets in the group. The same is of course true when horizontally grouping width for height widgets.

Widgets that trade height-for-width should set a reasonably large minimum width by way of property::Label::width-chars for instance. Widgets with static sizes as well as widgets that grow (such as ellipsizing text) need no such considerations.

GtkSizeGroup as GtkBuildable

Size groups can be specified in a UI definition by placing an <object> element with class="GtkSizeGroup" somewhere in the UI definition. The widgets that belong to the size group are specified by a <widgets> element that may contain multiple <widget> elements, one for each member of the size group. The ”name” attribute gives the id of the widget.

An example of a UI definition fragment with GtkSizeGroup:

⚠️ The following code is in xml ⚠️

<object class="GtkSizeGroup">
  <property name="mode">GTK_SIZE_GROUP_HORIZONTAL</property>
  <widgets>
    <widget name="radio1"/>
    <widget name="radio2"/>
  </widgets>
</object>

Implements

SizeGroupExt, glib::ObjectExt, BuildableExt, BuildableExtManual

Implementations

Create a new SizeGroup.

mode

the mode for the new size group.

Returns

a newly created SizeGroup

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

This method returns an instance of SizeGroupBuilder which can be used to create SizeGroup objects.

Trait Implementations

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

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

Formats the value using the given formatter. Read more

Feeds this value into the given Hasher. Read more

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

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

Compares and returns the maximum of two values. Read more

Compares and returns the minimum of two values. Read more

Restrict a value to a certain interval. Read more

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

This method tests for !=.

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

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

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

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

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

Returns the type identifier of Self.

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

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

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

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

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

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

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

Casts to T unconditionally. Read more

Casts to &T unconditionally. Read more

Performs the conversion.

Performs the conversion.

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

Returns the type of the object.

Returns the ObjectClass of the object. Read more

Returns the class of the object.

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

Returns the interface T of the object. Read more

Similar to Self::set_property but fails instead of panicking.

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

Similar to Self::set_property but fails instead of panicking.

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

Similar to Self::set_properties but fails instead of panicking.

Sets multiple properties of the object at once. Read more

Similar to Self::set_properties_from_value but fails instead of panicking.

Sets multiple properties of the object at once. Read more

Similar to Self::property but fails instead of panicking.

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

Similar to Self::property_value but fails instead of panicking.

Gets the property property_name of the object. Read more

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

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

Get the ParamSpec of the property property_name of this object.

Return all ParamSpec of the properties of this object.

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

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

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

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

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

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

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

Block a given signal handler. Read more

Unblock a given signal handler.

Stop emission of the currently emitted signal.

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

Similar to Self::connect but fails instead of panicking.

Connect to the signal signal_name on this object. Read more

Similar to Self::connect_id but fails instead of panicking.

Connect to the signal signal_id on this object. Read more

Similar to Self::connect_local but fails instead of panicking.

Connect to the signal signal_name on this object. Read more

Similar to Self::connect_local_id but fails instead of panicking.

Connect to the signal signal_id on this object. Read more

Similar to Self::connect_unsafe but fails instead of panicking.

Connect to the signal signal_name on this object. Read more

Similar to Self::connect_unsafe_id but fails instead of panicking.

Similar to Self::connect_closure but fails instead of panicking.

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

Similar to Self::connect_closure_id but fails instead of panicking.

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

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 Closure::invoke. Read more

Connect to the signal signal_id on this object. Read more

Similar to Self::emit but fails instead of panicking.

Emit signal by signal id. Read more

Similar to Self::emit_with_values but fails instead of panicking.

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

Similar to Self::emit_by_name but fails instead of panicking.

Emit signal by its name. Read more

Similar to Self::emit_by_name_with_values but fails instead of panicking.

Emit signal by its name. Read more

Similar to Self::emit_with_details but fails instead of panicking.

Emit signal by signal id with details. Read more

Similar to Self::emit_with_details_and_values but fails instead of panicking.

Emit signal by signal id with details. Read more

Disconnect a previously connected signal handler.

Connect to the notify signal of the object. Read more

Connect to the notify signal of the object. Read more

Connect to the notify signal of the object. Read more

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

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

Downgrade this object to a weak reference.

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

Returns the strong reference count of this object.

The resulting type after obtaining ownership.

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

🔬 This is a nightly-only experimental API. (toowned_clone_into)

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

Returns a SendValue clone of self.

Converts the given value to a String. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.