TextArea-class: TextArea widget

In termr: Modern Reactive Terminal Applications with Data Workflows

TextArea widget

Description

A multi-line text editor. See text_area().

Super class

Widget -> TextArea

Public fields

focusable

Text areas can be focused.

placeholder

Text shown while the area is empty.

line_numbers

Show a line number gutter?

wrap

Wrap long lines (TRUE) or scroll horizontally?

read_only

Block editing (cursor, selection, copy and search still work)?

language

Optional language name passed to the configured highlighter.

tab_size

Spaces inserted by Tab (and used for tabs in loaded text).

tab_behavior

"focus": Tab moves focus (default, safe in forms); "indent": Tab inserts spaces and Shift+Tab removes them.

auto_indent

Copy the indentation of the current line on Enter?

highlighter

Optional function ⁠(lines, state)⁠ returning a list of per-line data frames with 1-based inclusive start, end, token.

validate

NULL or ⁠function(value)⁠ returning NULL (valid) or an error message.

Active bindings

value

The text. Assigning replaces it (see set_text()).

text

The text (read-only alias of value).

lines

The lines as a character vector.

n_lines

Number of lines.

cursor_row, cursor_column

Cursor position, 1-based (column 1 is before the first character).

selection

The selected text ("" if none).

can_undo, can_redo

Is there something to undo / redo?

history_size

Characters held by the undo history.

match_count

Number of matches of the current search.

find_open

Is the find bar open?

valid

Does the value pass validate?

error

The validation message, or NULL.

Methods

Public methods

• TextArea$new()

• TextArea$default_style()

• TextArea$pseudo_states()

• TextArea$default_bindings()

• TextArea$on_key()

• TextArea$on_paste()

• TextArea$on_mouse_down()

• TextArea$on_mouse_move()

• TextArea$on_mouse_up()

• TextArea$on_mouse_scroll()

• TextArea$set_text()

• TextArea$insert()

• TextArea$select_range()

• TextArea$goto_line()

• TextArea$cursor_position()

• TextArea$copy()

• TextArea$cut()

• TextArea$undo()

• TextArea$redo()

• TextArea$find()

• TextArea$find_next()

• TextArea$find_previous()

• TextArea$replace()

• TextArea$replace_all()

• TextArea$clear_find()

• TextArea$action_cursor_left()

• TextArea$action_cursor_right()

• TextArea$action_cursor_up()

• TextArea$action_cursor_down()

• TextArea$action_line_start()

• TextArea$action_line_end()

• TextArea$action_document_start()

• TextArea$action_document_end()

• TextArea$action_word_left()

• TextArea$action_word_right()

• TextArea$action_page_up()

• TextArea$action_page_down()

• TextArea$action_select_left()

• TextArea$action_select_right()

• TextArea$action_select_up()

• TextArea$action_select_down()

• TextArea$action_select_line_start()

• TextArea$action_select_line_end()

• TextArea$action_select_document_start()

• TextArea$action_select_document_end()

• TextArea$action_select_word_left()

• TextArea$action_select_word_right()

• TextArea$action_select_page_up()

• TextArea$action_select_page_down()

• TextArea$action_select_all()

• TextArea$action_newline()

• TextArea$action_delete_left()

• TextArea$action_delete_right()

• TextArea$action_delete_word_left()

• TextArea$action_delete_word_right()

• TextArea$action_delete_to_line_start()

• TextArea$action_delete_to_line_end()

• TextArea$action_paste()

• TextArea$action_indent()

• TextArea$action_dedent()

• TextArea$action_undo()

• TextArea$action_redo()

• TextArea$action_open_find()

• TextArea$action_find_next()

• TextArea$action_find_previous()

• TextArea$action_open_replace()

• TextArea$action_open_goto()

• TextArea$content_width()

• TextArea$content_height()

• TextArea$paint()

• TextArea$clone()

Inherited methods

• Widget$add_class()
• Widget$ancestors()
• Widget$animate()
• Widget$arrange_children()
• Widget$bind()
• Widget$bind_reactive()
• Widget$bindings()
• Widget$blur()
• Widget$capture_mouse()
• Widget$child_clip()
• Widget$clear()
• Widget$computed_style()
• Widget$focus()
• Widget$format()
• Widget$get_state()
• Widget$has_class()
• Widget$invalidate()
• Widget$invalidate_paint()
• Widget$is_displayed()
• Widget$is_enabled()
• Widget$layout_descend()
• Widget$layout_differs()
• Widget$matches()
• Widget$mount()
• Widget$on()
• Widget$post_message()
• Widget$print()
• Widget$query()
• Widget$query_one()
• Widget$refresh()
• Widget$release_mouse()
• Widget$remove()
• Widget$remove_children()
• Widget$remove_class()
• Widget$render()
• Widget$render_lines()
• Widget$run_action()
• Widget$run_process()
• Widget$run_worker()
• Widget$set()
• Widget$set_interval()
• Widget$set_state()
• Widget$set_timeout()
• Widget$toggle_class()
• Widget$walk()

---

TextArea$new()

Create a text area.

Usage

TextArea$new(
  value = "",
  placeholder = "",
  id = NULL,
  classes = NULL,
  style = NULL,
  disabled = FALSE,
  line_numbers = FALSE,
  wrap = TRUE,
  read_only = FALSE,
  language = NULL,
  tab_size = 4L,
  tab_behavior = "focus",
  auto_indent = FALSE,
  validate = NULL,
  max_history = 200L,
  highlighter = NULL
)

Arguments

value

Initial text.

placeholder

Placeholder text.

id, classes, style, disabled

See Widget.

line_numbers, wrap, read_only, language, tab_size, tab_behavior, auto_indent

See the fields.

validate

Validation function.

max_history

Maximum number of undo steps.

highlighter

Optional function ⁠(lines, state)⁠ returning a list of per-line data frames with 1-based inclusive start, end, token.

---

TextArea$default_style()

The built-in style.

Usage

TextArea$default_style()

---

TextArea$pseudo_states()

Active states: focus, hover, disabled and invalid.

Usage

TextArea$pseudo_states()

---

TextArea$default_bindings()

Editing key bindings.

Usage

TextArea$default_bindings()

---

TextArea$on_key()

Printable keys replace the selection or are inserted at the cursor; Ctrl+C / Ctrl+X copy / cut a selection. While the find bar is open, keys edit the search text.

Usage

TextArea$on_key(event)

Arguments

event

A KeyEvent.

---

TextArea$on_paste()

Pasted text is inserted as one undo step; line breaks are kept.

Usage

TextArea$on_paste(event)

Arguments

event

A PasteEvent.

---

TextArea$on_mouse_down()

Click to place the cursor, shift+click and drag to select.

Usage

TextArea$on_mouse_down(event)

Arguments

event

A MouseEvent.

---

TextArea$on_mouse_move()

Dragging with the left button extends the selection.

Usage

TextArea$on_mouse_move(event)

Arguments

event

A MouseEvent.

---

TextArea$on_mouse_up()

Ends a drag selection.

Usage

TextArea$on_mouse_up(event)

Arguments

event

A MouseEvent.

---

TextArea$on_mouse_scroll()

The mouse wheel scrolls three rows.

Usage

TextArea$on_mouse_scroll(event)

Arguments

event

A MouseEvent.

---

TextArea$set_text()

Replace the whole text. Clears the undo history and moves the cursor to the start.

Usage

TextArea$set_text(text)

Arguments

text

A string (or character vector of lines).

---

TextArea$insert()

Insert text at the cursor, replacing the selection.

Usage

TextArea$insert(text, kind = NULL)

Arguments

text

A string; line breaks are kept.

kind

Internal: "type" merges into undo groups, "paste" does not.

---

TextArea$select_range()

Select a range (1-based rows and columns; column 1 is before the first character).

Usage

TextArea$select_range(start_row, start_column, end_row, end_column)

Arguments

start_row, start_column, end_row, end_column

The range.

---

TextArea$goto_line()

Move the cursor to a line.

Usage

TextArea$goto_line(row, column = 1L)

Arguments

row

Line number (1-based).

column

Column (1-based).

---

TextArea$cursor_position()

Cursor position. Columns count grapheme clusters and terminal display cells, both 1-based.

Usage

TextArea$cursor_position()

---

TextArea$copy()

Copy the selection to the app clipboard (and the system clipboard via OSC 52 when system = TRUE and supported).

Usage

TextArea$copy(system = TRUE)

Arguments

system

Also write to the system clipboard?

---

TextArea$cut()

Copy the selection and delete it.

Usage

TextArea$cut(system = TRUE)

Arguments

system

Also write to the system clipboard?

---

TextArea$undo()

Undo the last edit group.

Usage

TextArea$undo()

---

TextArea$redo()

Redo the last undone edit.

Usage

TextArea$redo()

---

TextArea$find()

Search for text and select the first match at or after the cursor.

Usage

TextArea$find(query, case_sensitive = FALSE, regex = FALSE)

Arguments

query

Text or regular expression (PCRE).

case_sensitive

Match case?

regex

Is query a regular expression? Invalid expressions raise an error.

Returns

TRUE if there is a match (invisibly).

---

TextArea$find_next()

Select the next match (wrapping around).

Usage

TextArea$find_next()

---

TextArea$find_previous()

Select the previous match (wrapping around).

Usage

TextArea$find_previous()

---

TextArea$replace()

Replace the current search match, or find query and replace its next match.

Usage

TextArea$replace(
  replacement,
  query = NULL,
  case_sensitive = FALSE,
  regex = FALSE
)

Arguments

replacement

Replacement text.

query

Optional search text; defaults to the active search.

case_sensitive, regex

Search options used when query is given.

---

TextArea$replace_all()

Replace all matches in one document edit. If the edit is larger than the bounded undo budget, it is applied without retaining an undo record.

Usage

TextArea$replace_all(query, replacement, case_sensitive = FALSE, regex = FALSE)

Arguments

query

Search text or regular expression.

replacement

Replacement text.

case_sensitive

Match case?

regex

Interpret query as a regular expression?

---

TextArea$clear_find()

Remove the search highlights and close the find bar.

Usage

TextArea$clear_find()

---

TextArea$action_cursor_left()

Move one character left.

Usage

TextArea$action_cursor_left()

---

TextArea$action_cursor_right()

Move one character right.

Usage

TextArea$action_cursor_right()

---

TextArea$action_cursor_up()

Move one row up.

Usage

TextArea$action_cursor_up()

---

TextArea$action_cursor_down()

Move one row down.

Usage

TextArea$action_cursor_down()

---

TextArea$action_line_start()

Move to the start of the line.

Usage

TextArea$action_line_start()

---

TextArea$action_line_end()

Move to the end of the line.

Usage

TextArea$action_line_end()

---

TextArea$action_document_start()

Move to the start of the text.

Usage

TextArea$action_document_start()

---

TextArea$action_document_end()

Move to the end of the text.

Usage

TextArea$action_document_end()

---

TextArea$action_word_left()

Move to the previous word.

Usage

TextArea$action_word_left()

---

TextArea$action_word_right()

Move to the next word.

Usage

TextArea$action_word_right()

---

TextArea$action_page_up()

Move one page up.

Usage

TextArea$action_page_up()

---

TextArea$action_page_down()

Move one page down.

Usage

TextArea$action_page_down()

---

TextArea$action_select_left()

Extend the selection left.

Usage

TextArea$action_select_left()

---

TextArea$action_select_right()

Extend the selection right.

Usage

TextArea$action_select_right()

---

TextArea$action_select_up()

Extend the selection up.

Usage

TextArea$action_select_up()

---

TextArea$action_select_down()

Extend the selection down.

Usage

TextArea$action_select_down()

---

TextArea$action_select_line_start()

Select to the start of the line.

Usage

TextArea$action_select_line_start()

---

TextArea$action_select_line_end()

Select to the end of the line.

Usage

TextArea$action_select_line_end()

---

TextArea$action_select_document_start()

Select to the start of the text.

Usage

TextArea$action_select_document_start()

---

TextArea$action_select_document_end()

Select to the end of the text.

Usage

TextArea$action_select_document_end()

---

TextArea$action_select_word_left()

Select to the previous word.

Usage

TextArea$action_select_word_left()

---

TextArea$action_select_word_right()

Select to the next word.

Usage

TextArea$action_select_word_right()

---

TextArea$action_select_page_up()

Extend the selection one page up.

Usage

TextArea$action_select_page_up()

---

TextArea$action_select_page_down()

Extend the selection one page down.

Usage

TextArea$action_select_page_down()

---

TextArea$action_select_all()

Select everything.

Usage

TextArea$action_select_all()

---

TextArea$action_newline()

Insert a line break (keeping the indentation when auto_indent is on).

Usage

TextArea$action_newline()

---

TextArea$action_delete_left()

Delete the selection or the character before the cursor.

Usage

TextArea$action_delete_left()

---

TextArea$action_delete_right()

Delete the selection or the character at the cursor.

Usage

TextArea$action_delete_right()

---

TextArea$action_delete_word_left()

Delete the word before the cursor.

Usage

TextArea$action_delete_word_left()

---

TextArea$action_delete_word_right()

Delete the word after the cursor.

Usage

TextArea$action_delete_word_right()

---

TextArea$action_delete_to_line_start()

Delete from the start of the line to the cursor.

Usage

TextArea$action_delete_to_line_start()

---

TextArea$action_delete_to_line_end()

Delete from the cursor to the end of the line (or the line break when the cursor is at the end).

Usage

TextArea$action_delete_to_line_end()

---

TextArea$action_paste()

Insert the app clipboard.

Usage

TextArea$action_paste()

---

TextArea$action_indent()

Insert spaces up to the next tab stop (or indent the selected lines).

Usage

TextArea$action_indent()

---

TextArea$action_dedent()

Remove up to one tab stop of leading spaces.

Usage

TextArea$action_dedent()

---

TextArea$action_undo()

Undo.

Usage

TextArea$action_undo()

---

TextArea$action_redo()

Redo.

Usage

TextArea$action_redo()

---

TextArea$action_open_find()

Open the find bar (Ctrl+F).

Usage

TextArea$action_open_find()

---

TextArea$action_find_next()

Select the next match (F3).

Usage

TextArea$action_find_next()

---

TextArea$action_find_previous()

Select the previous match (Shift+F3).

Usage

TextArea$action_find_previous()

---

TextArea$action_open_replace()

Open the find and replace bar (Ctrl+H).

Usage

TextArea$action_open_replace()

---

TextArea$action_open_goto()

Open the go-to-line bar (Ctrl+G).

Usage

TextArea$action_open_goto()

---

TextArea$content_width()

Natural width: the longest line (at most 120 columns).

Usage

TextArea$content_width()

---

TextArea$content_height()

Natural height: the number of lines (at most 1000).

Usage

TextArea$content_height(width)

Arguments

width

Content width.

---

TextArea$paint()

Draw the visible part of the text.

Usage

TextArea$paint(buffer, area, st)

Arguments

buffer

A ScreenBuffer.

area

Visible part of the region.

st

Computed style.

---

TextArea$clone()

The objects of this class are cloneable with this method.

Usage

TextArea$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

termr documentation built on Oct. 21, 2026, 5:13 p.m.