iced

Iced Docs

Source-verified docs generated from /src/content.

SearchGitHub

Reference

Element - Combo Box

Struct reference for iced::widget::ComboBox.

Version: latest | Last updated: 2026-02-19

Element - Combo Box

Authoritative source: ref/doc/iced/widget/struct.ComboBox.html.

# Rustdoc summary

A widget for searching and selecting a single value from a list of options.

# Verified type declaration

rust
pub struct ComboBox<'a, T, Message, Theme = Theme, Renderer = Renderer<Renderer, Renderer>>
where
    Theme: Catalog,
    Renderer: Renderer,{ /* private fields */ }

# When to use

Use this element struct when you need direct type-level control over a widget value.

# Why to use

It enables strongly typed composition and explicit builder method flows.

# Example References

  • ref/examples/combo_box/src/main.rs

# Inline Examples (from rustdoc)

rust
use iced::widget::combo_box;

struct State {
   fruits: combo_box::State<Fruit>,
   favorite: Option<Fruit>,
}

#[derive(Debug, Clone)]
enum Fruit {
    Apple,
    Orange,
    Strawberry,
    Tomato,
}

#[derive(Debug, Clone)]
enum Message {
    FruitSelected(Fruit),
}

fn view(state: &State) -> Element<'_, Message> {
    combo_box(
        &state.fruits,
        "Select your favorite fruit...",
        state.favorite.as_ref(),
        Message::FruitSelected
    )
    .into()
}

fn update(state: &mut State, message: Message) {
    match message {
        Message::FruitSelected(fruit) => {
            state.favorite = Some(fruit);
        }
    }
}

impl std::fmt::Display for Fruit {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.write_str(match self {
            Self::Apple => "Apple",
            Self::Orange => "Orange",
            Self::Strawberry => "Strawberry",
            Self::Tomato => "Tomato",
        })
    }
}

# Use this when...

  • You need the concrete widget struct type in signatures.
  • You are debugging type errors involving generic bounds.
  • You want lower-level control than constructor-only docs provide.

# Minimal example

rust
// Constructors usually produce this element type.
// Name the type explicitly only when type-level APIs need it.

# How it works

Element structs are the underlying widget types used by constructors. Most app code can stay constructor-first, then use element docs for advanced typing/customization.

# Common patterns

rust
// Use constructors in normal UI code,
// and reserve explicit element types for reusable abstractions.

# Gotchas / tips

  • You usually do not need to construct element structs directly.
  • Read trait bounds carefully when adding custom renderer/theme types.
  • If a method is missing, check the related module page.