Enum WidgetRef

pub enum WidgetRef {
    None,
    Owned(Rc<dyn Widget>),
    Borrowed(Weak<dyn Widget>),
    Keyed {
        owner_id: Option<WidgetId>,
        key: Key,
        widget: Box<WidgetRef>,
    },
}

Holds a reference to a widget, or not.

This is generally used when a widget can accept children as a parameter. It can either be Owned, Borrowed, None, or Keyed. A Keyed widget is one that may retain its state across parental rebuilds.

Variants

None

No widget.

Owned(Rc<dyn Widget>)

An owned widget.

Borrowed(Weak<dyn Widget>)

A borrowed widget.

Keyed

A keyed reference which may retain its state across parental rebuilds.

Fields

owner_id: Option<WidgetId>

key: Key

widget: Box<WidgetRef>

Implementations

impl WidgetRef

pub fn new<W>(widget: W) -> WidgetRef

where W: Widget,

pub fn is_valid(&self) -> bool

Returns true if the widget is still allocated in memory.

pub fn try_get(&self) -> Option<Rc<dyn Widget>>

pub fn get(&self) -> Rc<dyn Widget>

Panics

Will panic if the widget no longer exists, or the reference is empty.

pub fn get_type_id(&self) -> TypeId

Panics

Will panic if the widget no longer exists, or the reference is empty.

pub fn get_type_name(&self) -> &'static str

Panics

Will panic if the widget no longer exists, or the reference is empty.

pub fn try_downcast_ref<W>(&self) -> Option<Rc<W>>

where W: Widget,

Returns none of the widget is not the W type, or if it has been deallocated.

pub fn downcast_ref<W>(&self) -> Rc<W>

where W: Widget,

Panics

Will panic if the widget cannot be downcasted to the generic type.

Trait Implementations

impl Clone for WidgetRef

fn clone(&self) -> WidgetRef

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for WidgetRef

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

Formats the value using the given formatter.

impl Default for WidgetRef

fn default() -> WidgetRef

Returns the “default value” for a type.

impl From<&WidgetRef> for BuildResult

fn from(widget: &WidgetRef) -> BuildResult

Converts to this type from the input type.

impl From<&WidgetRef> for WidgetRef

fn from(widget: &WidgetRef) -> WidgetRef

Converts to this type from the input type.

impl From<App> for WidgetRef

fn from(widget: App) -> WidgetRef

Converts to this type from the input type.

impl<F> From<Builder<F>> for WidgetRef

where F: Fn(&WidgetContext<'_>) -> BuildResult + 'static,

fn from(builder: Builder<F>) -> WidgetRef

Converts to this type from the input type.

impl From<Button> for WidgetRef

fn from(widget: Button) -> WidgetRef

Converts to this type from the input type.

impl From<Column> for WidgetRef

fn from(widget: Column) -> WidgetRef

Converts to this type from the input type.

impl From<Drawable> for WidgetRef

fn from(widget: Drawable) -> WidgetRef

Converts to this type from the input type.

impl From<Padding> for WidgetRef

fn from(widget: Padding) -> WidgetRef

Converts to this type from the input type.

impl From<Row> for WidgetRef

fn from(widget: Row) -> WidgetRef

Converts to this type from the input type.

impl From<Spacing> for WidgetRef

fn from(widget: Spacing) -> WidgetRef

Converts to this type from the input type.

impl From<Text> for WidgetRef

fn from(widget: Text) -> WidgetRef

Converts to this type from the input type.

impl From<WidgetRef> for BuildResult

fn from(widget: WidgetRef) -> BuildResult

Converts to this type from the input type.

impl Into<Vec<WidgetRef>> for WidgetRef

fn into(self) -> Vec<WidgetRef>

Converts this type into the (usually inferred) input type.