Class SizeGroup

All Implemented Interfaces:
PointerInterface

public class SizeGroup extends Object
`GtkSizeGroup` groups widgets together so they all request the same size.

This is typically useful when you want a column of widgets to have the
same size, but you can’t use a `GtkGrid`.

In detail, the size requested for each widget in a `GtkSizeGroup` 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 [method@Gtk.SizeGroup.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 `GtkSizeGroup` 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.

`GtkSizeGroup` objects are referenced by each widget in the size group,
so once you have added all widgets to a `GtkSizeGroup`, 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 %GTK_SIZE_GROUP_HORIZONTAL or %GTK_SIZE_GROUP_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
%GTK_SIZE_GROUP_VERTICAL or %GTK_SIZE_GROUP_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 %GTK_SIZE_GROUP_VERTICAL or %GTK_SIZE_GROUP_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@Gtk.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`:
```xml
<object class="GtkSizeGroup">
<property name="mode">horizontal</property>
<widgets>
<widget name="radio1"/>
<widget name="radio2"/>
</widgets>
</object>
```

https://docs.gtk.org/gtk4/class.SizeGroup.html

  • Constructor Details

    • SizeGroup

      public SizeGroup(PointerContainer pointer)
    • SizeGroup

      public SizeGroup(int mode)
      Create a new `GtkSizeGroup`.
      Parameters:
      mode - the mode for the new size group.
  • Method Details

    • getClassHandler

      public static ClassHandler getClassHandler()
    • addWidget

      public void addWidget(@Nonnull Widget widget)
      Adds a widget to a `GtkSizeGroup`.

      In the future, the requisition
      of the widget will be determined as the maximum of its requisition
      and the requisition of the other widgets in the size group.
      Whether this applies horizontally, vertically, or in both directions
      depends on the mode of the size group.
      See [method@Gtk.SizeGroup.set_mode].

      When the widget is destroyed or no longer referenced elsewhere, it
      will be removed from the size group.
      Parameters:
      widget - the `GtkWidget` to add
    • getMode

      public int getMode()
      Gets the current mode of the size group.
      Returns:
      the current mode of the size group.
    • getWidgets

      public SList getWidgets()
      Returns the list of widgets associated with @size_group.
      Returns:
      a `GSList` of widgets. The list is owned by GTK and should not be modified.
    • removeWidget

      public void removeWidget(@Nonnull Widget widget)
      Removes a widget from a `GtkSizeGroup`.
      Parameters:
      widget - the `GtkWidget` to remove
    • setMode

      public void setMode(int mode)
      Sets the `GtkSizeGroupMode` of the size group.

      The mode of the size group determines whether the widgets in the
      size group should all have the same horizontal requisition
      (%GTK_SIZE_GROUP_HORIZONTAL) all have the same vertical requisition
      (%GTK_SIZE_GROUP_VERTICAL), or should all have the same requisition
      in both directions (%GTK_SIZE_GROUP_BOTH).
      Parameters:
      mode - the mode to set for the size group.
    • asBuildable

      public Buildable asBuildable()
      Implements interface Buildable. Call this to get access to interface functions.
      Returns:
      Buildable
    • getTypeID

      public static long getTypeID()
    • getParentTypeID

      public static long getParentTypeID()
    • getTypeSize

      public static TypeSystem.TypeSize getTypeSize()
    • getParentTypeSize

      public static TypeSystem.TypeSize getParentTypeSize()
    • getInstanceSize

      public static int getInstanceSize()