Struct tui_textarea::TextArea

pub struct TextArea<'a> { /* private fields */ }

A type to manage state of textarea.

TextArea::default creates an empty textarea. TextArea::new creates a textarea with given text lines. TextArea::from creates a textarea from an iterator of lines. TextArea::input handles key input. TextArea::widget builds a widget to render. And TextArea::lines returns line texts.

use tui_textarea::{TextArea, Input, Key};

let mut textarea = TextArea::default();

// Input 'a'
let input = Input { key: Key::Char('a'), ctrl: false, alt: false };
textarea.input(input);

// Get widget to render.
let widget = textarea.widget();

// Get lines as String.
println!("Lines: {:?}", textarea.lines());

Implementations

impl<'a> TextArea<'a>

pub fn new(lines: Vec<String>) -> Self

Create TextArea instance with given lines. If you have value other than Vec<String>, TextArea::from may be more useful.

use tui_textarea::TextArea;

let lines = vec!["hello".to_string(), "...".to_string(), "goodbye".to_string()];
let textarea = TextArea::new(lines);
assert_eq!(textarea.lines(), ["hello", "...", "goodbye"]);

pub fn input(&mut self, input: impl Into<Input>) -> bool

Handle a key input with default key mappings. For default key mappings, see the table in the module document. crossterm and termion features enable conversion from their own key event types into Input so this method can take the event values directly. This method returns if the input modified text contents or not in the textarea.

use tui_textarea::{TextArea, Key, Input};

let mut textarea = TextArea::default();

// Handle crossterm key events
let event: crossterm::event::Event = ...;
textarea.input(event);
if let crossterm::event::Event::Key(key) = event {
    textarea.input(key);
}

// Handle termion key events
let event: termion::event::Event = ...;
textarea.input(event);
if let termion::event::Event::Key(key) = event {
    textarea.input(key);
}

// Handle backend-agnostic key input
let input = Input { key: Key::Char('a'), ctrl: false, alt: false };
let modified = textarea.input(input);
assert!(modified);

pub fn input_without_shortcuts(&mut self, input: impl Into<Input>) -> bool

Handle a key input without default key mappings. This method handles only

• Single character input without modifier keys
• Tab
• Enter
• Backspace
• Delete

This method returns if the input modified text contents or not in the textarea.

This method is useful when you want to define your own key mappings and don’t want default key mappings. See ‘Define your own key mappings’ section in the module document.

pub fn insert_char(&mut self, c: char)

Insert a single character at current cursor position.

use tui_textarea::TextArea;

let mut textarea = TextArea::default();

textarea.insert_char('a');
assert_eq!(textarea.lines(), ["a"]);

pub fn insert_str<S: Into<String>>(&mut self, s: S) -> bool

Insert a string at current cursor position. Currently the string must not contain any newlines. This method returns if some text was inserted or not in the textarea.

use tui_textarea::TextArea;

let mut textarea = TextArea::default();

textarea.insert_str("hello");
assert_eq!(textarea.lines(), ["hello"]);

pub fn delete_str(&mut self, col: usize, chars: usize) -> bool

Delete a string in current cursor line. The chars parameter means number of characters, not a byte length of the string. This method returns if some text was deleted or not in the textarea.

use tui_textarea::TextArea;

let mut textarea = TextArea::from(["🐱🐶🐰🐮"]);

textarea.delete_str(1, 2);
assert_eq!(textarea.lines(), ["🐱🐮"]);

pub fn insert_tab(&mut self) -> bool

Insert a tab at current cursor position. Note that this method does nothing when the tab length is 0. This method returns if a tab string was inserted or not in the textarea. textarea.

use tui_textarea::TextArea;

let mut textarea = TextArea::from(["hi"]);

textarea.insert_tab();
assert_eq!(textarea.lines(), ["    hi"]);

pub fn insert_newline(&mut self)

Insert a newline at current cursor position.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["hi"]);

textarea.move_cursor(CursorMove::Forward);
textarea.insert_newline();
assert_eq!(textarea.lines(), ["h", "i"]);

pub fn delete_newline(&mut self) -> bool

Delete a newline from head of current cursor line. This method returns if a newline was deleted or not in the textarea.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["hello", "world"]);

textarea.move_cursor(CursorMove::Down);
textarea.delete_newline();
assert_eq!(textarea.lines(), ["helloworld"]);

pub fn delete_char(&mut self) -> bool

Delete one character before cursor. When the cursor is at head of line, the newline before the cursor will be removed. This method returns if some text was deleted or not in the textarea.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["abc"]);

textarea.move_cursor(CursorMove::Forward);
textarea.delete_char();
assert_eq!(textarea.lines(), ["bc"]);

pub fn delete_next_char(&mut self) -> bool

Delete one character next to cursor. When the cursor is at end of line, the newline next to the cursor will be removed. This method returns if a character was deleted or not in the textarea.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["abc"]);

textarea.move_cursor(CursorMove::Forward);
textarea.delete_next_char();
assert_eq!(textarea.lines(), ["ac"]);

pub fn delete_line_by_end(&mut self) -> bool

Delete string from cursor to end of the line. When the cursor is at end of line, the newline next to the cursor is removed. This method returns if some text was deleted or not in the textarea.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["abcde"]);

// Move to 'c'
textarea.move_cursor(CursorMove::Forward);
textarea.move_cursor(CursorMove::Forward);

textarea.delete_line_by_end();
assert_eq!(textarea.lines(), ["ab"]);

pub fn delete_line_by_head(&mut self) -> bool

Delete string from cursor to head of the line. When the cursor is at head of line, the newline before the cursor will be removed. This method returns if some text was deleted or not in the textarea.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["abcde"]);

// Move to 'c'
textarea.move_cursor(CursorMove::Forward);
textarea.move_cursor(CursorMove::Forward);

textarea.delete_line_by_head();
assert_eq!(textarea.lines(), ["cde"]);

pub fn delete_word(&mut self) -> bool

Delete a word before cursor. Word boundary appears at spaces, punctuations, and others. For example fn foo(a) consists of words fn, foo, (, a, ). When the cursor is at head of line, the newline before the cursor will be removed.

This method returns if some text was deleted or not in the textarea.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["aaa bbb ccc"]);

textarea.move_cursor(CursorMove::End);

textarea.delete_word();
assert_eq!(textarea.lines(), ["aaa bbb "]);
textarea.delete_word();
assert_eq!(textarea.lines(), ["aaa "]);

pub fn delete_next_word(&mut self) -> bool

Delete a word next to cursor. Word boundary appears at spaces, punctuations, and others. For example fn foo(a) consists of words fn, foo, (, a, ). When the cursor is at end of line, the newline next to the cursor will be removed.

This method returns if some text was deleted or not in the textarea.

use tui_textarea::TextArea;

let mut textarea = TextArea::from(["aaa bbb ccc"]);

textarea.delete_next_word();
assert_eq!(textarea.lines(), [" bbb ccc"]);
textarea.delete_next_word();
assert_eq!(textarea.lines(), [" ccc"]);

pub fn paste(&mut self) -> bool

Paste a string previously deleted by TextArea::delete_line_by_head, TextArea::delete_line_by_end, TextArea::delete_word, TextArea::delete_next_word. This method returns if some text was inserted or not in the textarea.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["aaa bbb ccc"]);

textarea.delete_next_word();
textarea.move_cursor(CursorMove::End);
textarea.paste();
assert_eq!(textarea.lines(), [" bbb cccaaa"]);

pub fn move_cursor(&mut self, m: CursorMove)

Move the cursor to the position specified by the CursorMove parameter. For each kind of cursor moves, see the document of CursorMove.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["abc", "def"]);

textarea.move_cursor(CursorMove::Forward);
assert_eq!(textarea.cursor(), (0, 1));
textarea.move_cursor(CursorMove::Down);
assert_eq!(textarea.cursor(), (1, 1));

pub fn undo(&mut self) -> bool

Undo the last modification. This method returns if the undo modified text contents or not in the textarea.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["abc def"]);

textarea.delete_next_word();
assert_eq!(textarea.lines(), [" def"]);
textarea.undo();
assert_eq!(textarea.lines(), ["abc def"]);

pub fn redo(&mut self) -> bool

Redo the last undo change. This method returns if the redo modified text contents or not in the textarea.

use tui_textarea::{TextArea, CursorMove};

let mut textarea = TextArea::from(["abc def"]);

textarea.delete_next_word();
assert_eq!(textarea.lines(), [" def"]);
textarea.undo();
assert_eq!(textarea.lines(), ["abc def"]);
textarea.redo();
assert_eq!(textarea.lines(), [" def"]);

pub fn widget(&'a self) -> impl Widget + 'a

Build a tui-rs widget to render the current state of the textarea. The widget instance returned from this method can be rendered with tui::terminal::Frame::render_widget.

use tui::backend::CrosstermBackend;
use tui::layout::{Constraint, Direction, Layout};
use tui::Terminal;
use tui_textarea::TextArea;

let mut textarea = TextArea::default();

let layout = Layout::default()
    .direction(Direction::Vertical)
    .constraints([Constraint::Min(1)].as_ref());
let backend = CrosstermBackend::new(std::io::stdout());
let mut term = Terminal::new(backend).unwrap();

loop {
    term.draw(|f| {
        let chunks = layout.split(f.size());
        let widget = textarea.widget();
        f.render_widget(widget, chunks[0]);
    }).unwrap();

    // ...
}

pub fn set_style(&mut self, style: Style)

Set the style of textarea. By default, textarea is not styled.

use tui::style::{Style, Color};
use tui_textarea::TextArea;

let mut textarea = TextArea::default();
let style = Style::default().fg(Color::Red);
textarea.set_style(style);
assert_eq!(textarea.style(), style);

pub fn style(&self) -> Style

Get the current style of textarea.

pub fn set_block(&mut self, block: Block<'a>)

Set the block of textarea. By default, no block is set.

use tui_textarea::TextArea;
use tui::widgets::{Block, Borders};

let mut textarea = TextArea::default();
let block = Block::default().borders(Borders::ALL).title("Block Title");
textarea.set_block(block);
assert!(textarea.block().is_some());

pub fn remove_block(&mut self)

Remove the block of textarea which was set by TextArea::set_block.

use tui_textarea::TextArea;
use tui::widgets::{Block, Borders};

let mut textarea = TextArea::default();
let block = Block::default().borders(Borders::ALL).title("Block Title");
textarea.set_block(block);
textarea.remove_block();
assert!(textarea.block().is_none());

pub fn block<'s>(&'s self) -> Option<&'s Block<'a>>

Get the block of textarea if exists.

pub fn set_tab_length(&mut self, len: u8)

Set the length of tab character. Due to limitation of tui-rs, hard tab is not supported. Setting 0 disables tab inputs.

use tui_textarea::{TextArea, Input, Key};

let mut textarea = TextArea::default();
let tab_input = Input { key: Key::Tab, ctrl: false, alt: false };

textarea.set_tab_length(8);
textarea.input(tab_input.clone());
assert_eq!(textarea.lines(), ["        "]);

textarea.set_tab_length(2);
textarea.input(tab_input);
assert_eq!(textarea.lines(), ["          "]);

pub fn tab_length(&self) -> u8

Get how many spaces are used for representing tab character. The default value is 4.

pub fn set_max_histories(&mut self, max: usize)

Set how many modifications are remembered for undo/redo. Setting 0 disables undo/redo.

pub fn max_histories(&self) -> usize

Get how many modifications are remembered for undo/redo. The default value is 50.

pub fn set_cursor_line_style(&mut self, style: Style)

Set the style of line at cursor. By default, the cursor line is styled with underline. To stop styling the cursor line, set the default style.

use tui::style::{Style, Color};
use tui_textarea::TextArea;

let mut textarea = TextArea::default();

let style = Style::default().fg(Color::Red);
textarea.set_cursor_line_style(style);
assert_eq!(textarea.cursor_line_style(), style);

// Disable cursor line style
textarea.set_cursor_line_style(Style::default());

pub fn cursor_line_style(&self) -> Style

Get the style of cursor line. By default it is styled with underline.

pub fn set_line_number_style(&mut self, style: Style)

Set the style of line number. By setting the style with this method, line numbers are drawn in textarea, meant that line numbers are disabled by default. If you want to show line numbers but don’t want to style them, set the default style.

use tui::style::{Style, Color};
use tui_textarea::TextArea;

let mut textarea = TextArea::default();

// Show line numbers in dark gray background
let style = Style::default().bg(Color::DarkGray);
textarea.set_line_number_style(style);
assert_eq!(textarea.line_number_style(), Some(style));

pub fn remove_line_number(&mut self)

Remove the style of line number which was set by TextArea::set_line_number_style. After calling this method, Line numbers will no longer be shown.

use tui::style::{Style, Color};
use tui_textarea::TextArea;

let mut textarea = TextArea::default();

textarea.set_line_number_style(Style::default().bg(Color::DarkGray));
textarea.remove_line_number();
assert_eq!(textarea.line_number_style(), None);

pub fn line_number_style(&self) -> Option<Style>

Get the style of line number if set.

pub fn set_cursor_style(&mut self, style: Style)

Set the style of cursor. By default, a cursor is rendered in the reversed color. Setting the same style as cursor line hides a cursor.

use tui::style::{Style, Color};
use tui_textarea::TextArea;

let mut textarea = TextArea::default();

let style = Style::default().bg(Color::Red);
textarea.set_cursor_style(style);
assert_eq!(textarea.cursor_style(), style);

pub fn cursor_style(&self) -> Style

Get the style of cursor.

pub fn lines(&'a self) -> &'a [String]

Get slice of line texts. This method borrows the content, but not moves. Note that the returned slice will never be empty because an empty text means a slice containing one empty line. This is correct since any text file must end with a newline.

use tui_textarea::TextArea;

let mut textarea = TextArea::default();
assert_eq!(textarea.lines(), [""]);

textarea.insert_char('a');
assert_eq!(textarea.lines(), ["a"]);

textarea.insert_newline();
assert_eq!(textarea.lines(), ["a", ""]);

textarea.insert_char('b');
assert_eq!(textarea.lines(), ["a", "b"]);

pub fn into_lines(self) -> Vec<String>

Convert TextArea instance into line texts.

use tui_textarea::TextArea;

let mut textarea = TextArea::default();

textarea.insert_char('a');
textarea.insert_newline();
textarea.insert_char('b');

assert_eq!(textarea.into_lines(), ["a", "b"]);

pub fn cursor(&self) -> (usize, usize)

Get the current cursor position. 0-base character-wise (row, col) cursor position.

use tui_textarea::TextArea;

let mut textarea = TextArea::default();
assert_eq!(textarea.cursor(), (0, 0));

textarea.insert_char('a');
textarea.insert_newline();
textarea.insert_char('b');

assert_eq!(textarea.cursor(), (1, 1));

pub fn is_empty(&self) -> bool

Check if the textarea has a empty content.

use tui_textarea::TextArea;

let textarea = TextArea::default();
assert!(textarea.is_empty());

let textarea = TextArea::from(["hello"]);
assert!(!textarea.is_empty());

pub fn yank_text(&'a self) -> &'a str

Get the yanked text. Text is automatically yanked when deleting strings by TextArea::delete_line_by_head, TextArea::delete_line_by_end, TextArea::delete_word, TextArea::delete_next_word.

use tui_textarea::TextArea;

let mut textarea = TextArea::from(["abc"]);

textarea.delete_next_word();
assert_eq!(textarea.yank_text(), "abc");

pub fn set_yank_text(&mut self, text: impl Into<String>)

Set a yanked text. The text can be inserted by TextArea::paste. The string passed to method must not contain any newlines.

use tui_textarea::TextArea;

let mut textarea = TextArea::default();

textarea.set_yank_text("hello, world");
textarea.paste();
assert_eq!(textarea.lines(), ["hello, world"]);

Trait Implementations

impl<'a> Default for TextArea<'a>

Create TextArea instance with empty text content.

use tui_textarea::TextArea;

let textarea = TextArea::default();
assert_eq!(textarea.lines(), [""]);
assert!(textarea.is_empty());

fn default() -> Self

Returns the “default value” for a type.

impl<'a, I> From<I> for TextArea<'a> where
    I: IntoIterator,
    I::Item: Into<String>, 

Convert any iterator whose elements can be converted into String into TextArea. Each String element is handled as line. Ensure that the strings don’t contain any newlines. This method is useful to create TextArea from std::str::Lines.

use tui_textarea::TextArea;

// From `String`
let text = "hello\nworld";
let textarea = TextArea::from(text.lines());
assert_eq!(textarea.lines(), ["hello", "world"]);

// From array of `&str`
let textarea = TextArea::from(["hello", "world"]);
assert_eq!(textarea.lines(), ["hello", "world"]);

// From slice of `&str`
let slice = &["hello", "world"];
let textarea = TextArea::from(slice.iter().copied());
assert_eq!(textarea.lines(), ["hello", "world"]);

fn from(i: I) -> Self

Converts to this type from the input type.

impl<'a, S: Into<String>> FromIterator<S> for TextArea<'a>

Collect line texts from iterator as TextArea. It is useful when creating a textarea with text read from a file. Iterator::collect handles errors which may happen on reading each lines. The following example reads text from a file efficiently line-by-line.

use std::fs;
use std::io::{self, BufRead};
use std::path::Path;
use tui_textarea::TextArea;

fn read_from_file<'a>(path: impl AsRef<Path>) -> io::Result<TextArea<'a>> {
    let file = fs::File::open(path.as_ref())?;
    io::BufReader::new(file).lines().collect()
}

fn from_iter<I: IntoIterator<Item = S>>(iter: I) -> Self

Creates a value from an iterator.