`TextareaRenderable` — multi-line editor

A full multi-line text editor widget: cursor movement, selection, line operations, undo/redo, configurable key bindings, and a submit callback. Focusable. This is the widget behind multi-line prompt inputs.

TextareaRenderable::new(options: TextareaOptions) -> Self

`TextareaOptions`

Field	Default	Meaning
`initial_value`	`None`	Starting content.
`background_color` / `text_color`	transparent / white	Base colors.
`focused_background_color` / `focused_text_color`	`#1a1a1a` / white	Colors while focused.
`placeholder`	`None`	Ghost text when empty.
`placeholder_color`	muted	Placeholder color.
`key_bindings`	`None` (defaults)	`TextareaKeyBinding` list.
`wrap`	`true`	Word-wrap long lines.
`min_height` / `max_height`	—	Editor height bounds.

pub struct TextareaKeyBinding {
    pub name: String,
    pub ctrl: bool, pub meta: bool, pub shift: bool, pub super_key: bool,
    pub action: TextareaAction,
}

`TextareaAction`

The editor commands a key binding can trigger:

Movement: MoveLeft, MoveRight, MoveUp, MoveDown, LineHome, LineEnd, VisualLineHome, VisualLineEnd, BufferHome, BufferEnd, WordForward, WordBackward.
Selection: SelectLeft … SelectDown, SelectLineHome/End, SelectVisualLineHome/End, SelectBufferHome/End, SelectWordForward, SelectWordBackward, SelectAll.
Editing: Backspace, Delete, DeleteLine, DeleteToLineEnd, DeleteToLineStart, DeleteWordForward, DeleteWordBackward, Newline.
History: Undo, Redo.
Submit: Submit (fires the on_submit callback).

Callbacks and focus

pub type SubmitEvent = ();
pub type OnSubmitCallback = Box<dyn FnMut()>;

pub fn set_on_submit(&mut self, handler: Option<OnSubmitCallback>)
pub const fn focus(&mut self)
pub const fn blur(&mut self)
pub const fn is_focused(&self) -> bool

set_on_submit installs a callback fired when the user submits; pass None to clear it.

Reading and writing content

value() -> String              // current content
set_value(&str)                // replace content
placeholder() -> Option<&str>
set_placeholder(Option<String>)

Editing commands

All return bool — true when the command changed state:

Group	Methods
Insert	`insert_text(&str)`, `new_line()`, `submit()`
Delete	`delete_char_backward()`, `delete_char()`, `delete_line()`, `delete_to_line_end()`, `delete_to_line_start()`
Move	`move_cursor_left/right/up/down()`, `goto_buffer_home/end()`, `goto_line_home/end()`
History	`undo()`, `redo()`
Select	`select_all()`

Example — a small “submit on Enter” loop:

use cosh_tui::core::renderables::textarea::{TextareaRenderable, TextareaOptions};

let mut editor = TextareaRenderable::new(TextareaOptions {
    initial_value: Some("line one".into()),
    ..Default::default()
});

editor.insert_text("\nline two");    // becomes multi-line
editor.move_cursor_up();             // cursor back to line one
assert_eq!(editor.value(), "line one\nline two");

Styling: set_focused_background_color / set_focused_text_color take Option<ColorInput>.

Next: select — vertical option list.

TextareaRenderable — multi-line editor

TextareaOptions