Struct DropdownState 

pub struct DropdownState {
    pub selected: usize,
    pub options: Vec<String>,
    pub values: Vec<String>,
    pub label: String,
    pub open: bool,
    pub focus: FocusState,
    pub scroll_offset: usize,
    pub max_visible: usize,
    pub hover_index: Option<usize>,
    /* private fields */
}

State for a dropdown control

Fields

selected: usize

Currently selected index

options: Vec<String>

Display names for options (shown in UI)

values: Vec<String>

Actual values for options (stored in config) If empty, options are used as values

label: String

Label displayed before the dropdown

open: bool

Whether the dropdown is currently open

focus: FocusState

Focus state

scroll_offset: usize

Scroll offset for long option lists

max_visible: usize

Maximum visible options (set during render)

hover_index: Option<usize>

Hover index for mouse hover indication (when open)

Implementations

impl DropdownState

pub fn handle_mouse( &mut self, event: MouseEvent, layout: &DropdownLayout, ) -> Option<DropdownEvent>

Handle a mouse event for this dropdown

Arguments

• event - The mouse event to handle
• layout - The control’s rendered layout for hit testing

Returns

• Some(DropdownEvent) if the event was consumed
• None if the event was not relevant

pub fn handle_key(&mut self, key: KeyEvent) -> Option<DropdownEvent>

Handle a keyboard event for this dropdown

Returns

• Some(DropdownEvent) if the event was consumed
• None if the event was not relevant

impl DropdownState

pub fn new(options: Vec<String>, label: impl Into<String>) -> Self

Create a new dropdown state where display names equal values

pub fn with_values( options: Vec<String>, values: Vec<String>, label: impl Into<String>, ) -> Self

Create a dropdown with separate display names and values

pub fn with_selected(self, index: usize) -> Self

Set the initially selected index

pub fn with_focus(self, focus: FocusState) -> Self

Set the focus state

pub fn is_enabled(&self) -> bool

Check if the control is enabled

pub fn selected_value(&self) -> Option<&str>

Get the currently selected value (for storing in config)

pub fn selected_option(&self) -> Option<&str>

Get the currently selected display name (for UI)

pub fn index_of_value(&self, value: &str) -> Option<usize>

Find the index of a value

pub fn toggle_open(&mut self)

Toggle the dropdown open/closed

pub fn cancel(&mut self)

Cancel the dropdown (restore original selection and close)

pub fn confirm(&mut self)

Confirm the selection and close

pub fn select_next(&mut self)

Select the next option

pub fn select_prev(&mut self)

Select the previous option

pub fn select(&mut self, index: usize)

Select an option by index

pub fn ensure_visible(&mut self)

Ensure the selected item is visible within the scroll view

pub fn scroll_by(&mut self, delta: i32)

Scroll the dropdown by a delta (positive = down, negative = up)

pub fn needs_scrollbar(&self) -> bool

Check if scrollbar should be shown

pub fn scroll_fraction(&self) -> f32

Get the scroll position as a fraction (0.0 to 1.0) for scrollbar rendering

Trait Implementations

impl Clone for DropdownState

fn clone(&self) -> DropdownState

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DropdownState

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

Formats the value using the given formatter.