Struct TextEdit 

pub struct TextEdit { /* private fields */ }

An editable line of text with a cursor and an optional selection.

Implementations

impl TextEdit

pub fn new(text: &str) -> Self

Start editing text with the cursor at the end.

pub fn text(&self) -> String

pub fn chars(&self) -> &[char]

The buffer itself. Callers that only need to measure or slice the text use this instead of text, which allocates a fresh String every call — and the platform’s input handler asks several times per keystroke.

pub fn is_empty(&self) -> bool

pub fn len(&self) -> usize

Length in chars, which is also the last valid cursor position.

pub fn cursor(&self) -> usize

The cursor as a char index.

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

Move the cursor, dropping any selection. Out-of-range values clamp.

pub fn set_selection(&mut self, start: usize, end: usize)

Select start..end and leave the cursor at end, so a following Shift+Arrow extends from the edge the user last moved.

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

Move the selection’s free edge to index, opening a selection anchored at the cursor if there isn’t one. This is Shift+click and mouse drag.

pub fn set_text(&mut self, text: &str)

Replace everything, as a programmatic set: the history is dropped because the old text is no longer something the user can undo back to. That also releases whatever the history was holding.

pub fn byte_of(&self, index: usize) -> usize

Byte offset into text for a char index. Shaped-line geometry is addressed in bytes, the edit model in chars.

pub fn char_of(&self, byte: usize) -> usize

Char index for a byte offset, rounding up to the next char boundary.

pub fn word_at(&self, index: usize) -> (usize, usize)

The word surrounding index as (start, end) char indices — what a double-click selects. A click in whitespace takes the whitespace run.

pub fn undo(&mut self) -> bool

Undo the last edit. Returns whether there was one.

pub fn redo(&mut self) -> bool

Redo the last undone edit. Returns whether there was one.

pub fn break_undo(&mut self)

End the current coalescing run, so the next edit starts a fresh undo step. Callers use this at word boundaries and on paste.

pub fn selection(&self) -> Option<(usize, usize)>

The selected span (start, end) as char indices, or None if the selection is empty/collapsed.

pub fn has_selection(&self) -> bool

pub fn selected_text(&self) -> Option<String>

The selected text, or None when nothing is selected.

pub fn select_all(&mut self)

Select the whole line.

pub fn clear_selection(&mut self)

Drop any selection, keeping the cursor put.

pub fn collapse_selection_start(&mut self) -> bool

pub fn collapse_selection_end(&mut self) -> bool

pub fn delete_selection(&mut self) -> bool

Delete the selected text (if any), leaving the cursor at its start. Returns whether anything was removed.

pub fn pre_move(&mut self, extend: bool)

Prepare for a cursor move: with extend (Shift held) anchor a selection at the current cursor if one isn’t already open; otherwise drop it.

pub fn split_selection(&self) -> Option<(String, String, String)>

The text split around the selection: (before, selected, after), or None when nothing is selected.

pub fn insert(&mut self, s: &str)

Insert s at the cursor, replacing any selection, advancing past it.

pub fn replace_range(&mut self, range: Range<usize>, s: &str)

Replace the char range range with s, leaving the cursor after it. This is the entry point the platform’s text-input handler drives, so it takes an explicit range rather than using the selection.

pub fn backspace(&mut self) -> bool

Delete the selection, or the char before the cursor. Returns whether anything changed.

pub fn delete(&mut self) -> bool

Delete the selection, or the char at the cursor. Returns whether anything changed.

pub fn left(&mut self)

pub fn right(&mut self)

pub fn home(&mut self)

pub fn end(&mut self)

pub fn line_home(&mut self)

pub fn line_end(&mut self)

pub fn word_left(&mut self)

Move left to the start of the previous word (Option+Left on macOS).

pub fn word_right(&mut self)

Move right past the end of the next word (Option+Right on macOS).

pub fn delete_word_back(&mut self) -> bool

Delete the word before the cursor (Option+Backspace). Returns whether anything changed.

pub fn delete_word_forward(&mut self) -> bool

Delete the word after the cursor (Option+Delete). Returns whether anything changed.

pub fn delete_to_start(&mut self) -> bool

Delete from the cursor to the line start (Cmd+Backspace). Returns whether anything changed.

pub fn delete_to_end(&mut self) -> bool

Delete from the cursor to the line end (Cmd+Delete / Ctrl+K). Returns whether anything changed.

pub fn split(&self) -> (String, String)

The text before and after the cursor, for rendering a caret between.

pub fn up(&mut self)

Move the cursor up one line, keeping the column where possible. Multiline only (single-line text has nowhere to go).

pub fn down(&mut self)

Move the cursor down one line, keeping the column where possible.

Trait Implementations

impl Clone for TextEdit

fn clone(&self) -> TextEdit

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TextEdit

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

Formats the value using the given formatter.

impl Default for TextEdit

fn default() -> TextEdit

Returns the “default value” for a type.