Struct gtk::CellLayout

pub struct CellLayout(_, _);

CellLayout is an interface to be implemented by all objects which want to provide a TreeViewColumn like API for packing cells, setting attributes and data funcs.

One of the notable features provided by implementations of CellLayout are attributes. Attributes let you set the properties in flexible ways. They can just be set to constant values like regular properties. But they can also be mapped to a column of the underlying tree model with CellLayout::set_attributes, which means that the value of the attribute can change from cell to cell as they are rendered by the cell renderer. Finally, it is possible to specify a function with CellLayout::set_cell_data_func that is called to determine the value of the attribute for each cell that is rendered.

GtkCellLayouts as Buildable

Implementations of CellLayout which also implement the Buildable interface (CellView, IconView, ComboBox, EntryCompletion, TreeViewColumn) accept CellRenderer objects as <child> elements in UI definitions. They support a custom <attributes> element for their children, which can contain multiple <attribute> elements. Each <attribute> element has a name attribute which specifies a property of the cell renderer; the content of the element is the attribute value.

This is an example of a UI definition fragment specifying attributes:

combo = g_object_new (GTK_TYPE_COMBO_BOX, "cell-area", my_cell_area, NULL);

to use a custom cell area with a combo box. But construct properties are only initialized after instance init functions have run, which means that using functions which rely on the existence of the cell area in your subclass’ init function will cause the default cell area to be instantiated. In this case, a provided construct property value will be ignored (with a warning, to alert you to the problem).

static void
my_combo_box_init (MyComboBox *b)
{
  GtkCellRenderer *cell;

  cell = gtk_cell_renderer_pixbuf_new ();
  // The following call causes the default cell area for combo boxes,
  // a GtkCellAreaBox, to be instantiated
  gtk_cell_layout_pack_start (GTK_CELL_LAYOUT (b), cell, FALSE);
  ...
}

GtkWidget *
my_combo_box_new (GtkCellArea *area)
{
  // This call is going to cause a warning about area being ignored
  return g_object_new (MY_TYPE_COMBO_BOX, "cell-area", area, NULL);
}

If supporting alternative cell areas with your derived widget is not important, then this does not have to concern you. If you want to support alternative cell areas, you can do so by moving the problematic calls out of init and into a constructor for your class.

Implements

CellLayoutExt

Trait Implementations

impl Clone for CellLayout

fn clone(&self) -> CellLayout

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for CellLayout

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for CellLayout

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for CellLayout

impl Hash for CellLayout

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl IsA<CellLayout> for AppChooserButton

impl IsA<CellLayout> for CellArea

impl IsA<CellLayout> for CellAreaBox

impl IsA<CellLayout> for CellView

impl IsA<CellLayout> for ComboBox

impl IsA<CellLayout> for ComboBoxText

impl IsA<CellLayout> for EntryCompletion

impl IsA<CellLayout> for IconView

impl IsA<CellLayout> for TreeViewColumn

impl Ord for CellLayout

fn cmp(&self, other: &CellLayout) -> Ordering

This method returns an [Ordering] between self and other.

#[must_use]fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]fn clamp(self, min: Self, max: Self) -> Self

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

Restrict a value to a certain interval.

impl<T: ObjectType> PartialEq<T> for CellLayout

fn eq(&self, other: &T) -> bool

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

#[must_use]fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<T: ObjectType> PartialOrd<T> for CellLayout

fn partial_cmp(&self, other: &T) -> Option<Ordering>

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

#[must_use]fn lt(&self, other: &Rhs) -> bool

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

#[must_use]fn le(&self, other: &Rhs) -> bool

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

#[must_use]fn gt(&self, other: &Rhs) -> bool

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

#[must_use]fn ge(&self, other: &Rhs) -> bool

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

impl StaticType for CellLayout

fn static_type() -> Type

Returns the type identifier of Self.