Struct Responsive 

pub struct Responsive {
    pub id: Option<WidgetId>,
    pub query: ResponsiveQuery,
    pub cases: Vec<ResponsiveCase>,
    pub fallback: Widget,
}

Selects a widget branch using declarative viewport or container breakpoints.

Prefer Responsive over manually reading view.viewport_size() when the rule is only “render this child below or above this width”. Keep viewport reads for cases that also depend on app state, environment values, or measured geometry.

Example

Responsive::new(DesktopShell)
    .id(WidgetId::explicit("mail.responsive"))
    .case(ResponsiveCase::max_width(900.0, PhoneShell))
    .case(ResponsiveCase::between(900.0, 1200.0, TabletShell))
    .into()

Every branch is lowered, even though layout displays only the selected one. Build each branch independently rather than cloning a Widget value, and keep explicit widget IDs unique across the complete responsive tree.

Fields

id: Option<WidgetId>

Optional stable identity for diagnostics and retained child identity.

query: ResponsiveQuery

Width source used to evaluate the responsive cases.

cases: Vec<ResponsiveCase>

Ordered cases; the first matching case wins.

fallback: Widget

Child rendered when no case matches.

Implementations

impl Responsive

pub fn new(fallback: impl Into<Widget>) -> Self

Creates a responsive switch with a required fallback branch.

pub fn id(self, id: WidgetId) -> Self

Sets an explicit identity for deterministic inspection and diffing.

pub fn case(self, case: ResponsiveCase) -> Self

Appends an ordered responsive case.

pub fn query(self, query: ResponsiveQuery) -> Self

Selects viewport or parent-container width evaluation.

pub fn container_query(self) -> Self

Evaluates cases against the immediate parent constraints.

Trait Implementations

impl Clone for Responsive

fn clone(&self) -> Responsive

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Responsive

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Responsive

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl From<Responsive> for Widget

fn from(w: Responsive) -> Self

Converts to this type from the input type.

impl Serialize for Responsive

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.