Struct zng_app::widget::builder::WhenInfo

pub struct WhenInfo {
    pub inputs: Box<[WhenInput]>,
    pub state: BoxedVar<bool>,
    pub assigns: Vec<Box<dyn PropertyArgs>>,
    pub build_action_data: Vec<((PropertyId, &'static str), WhenBuildAction)>,
    pub expr: &'static str,
    pub location: SourceLocation,
}

Represents a when block in a widget.

Fields

inputs: Box<[WhenInput]>

Properties referenced in the when condition expression.

They are type erased BoxedVar<T> instances that are late-inited, other variable references (*#{var}) are embedded in the build expression and cannot be modified. Note that the state sticks to the first late-inited vars that it uses, the variable only updates after clone, this cloning happens naturally when instantiating a widget more then once.

state: BoxedVar<bool>

Output of the when expression.

Panics if used outside of the widget context.

assigns: Vec<Box<dyn PropertyArgs>>

Properties assigned in the when block, in the build widget they are joined with the default value and assigns from other when blocks into a single property instance set to when_var! inputs.

build_action_data: Vec<((PropertyId, &'static str), WhenBuildAction)>

Data associated with the when condition in the build action.

expr: &'static str

The condition expression code.

location: SourceLocation

When declaration location.

Trait Implementations

impl Clone for WhenInfo

fn clone(&self) -> WhenInfo

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for WhenInfo

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

Formats the value using the given formatter.