egui/egui/src/widgets/text_edit.rs

1400 lines
48 KiB
Rust

use crate::{output::OutputEvent, util::undoer::Undoer, *};
use epaint::text::{cursor::*, Galley, LayoutJob};
use std::ops::Range;
use std::sync::Arc;
#[derive(Clone, Debug, Default)]
#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
#[cfg_attr(feature = "serde", serde(default))]
pub(crate) struct State {
cursorp: Option<CursorPair>,
#[cfg_attr(feature = "serde", serde(skip))]
undoer: Undoer<(CCursorPair, String)>,
// If IME candidate window is shown on this text edit.
#[cfg_attr(feature = "serde", serde(skip))]
has_ime: bool,
// Visual offset when editing singleline text bigger than the width.
#[cfg_attr(feature = "serde", serde(skip))]
singleline_offset: f32,
}
#[derive(Clone, Copy, Debug, Default)]
#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
pub struct CursorPair {
/// When selecting with a mouse, this is where the mouse was released.
/// When moving with e.g. shift+arrows, this is what moves.
/// Note that the two ends can come in any order, and also be equal (no selection).
pub primary: Cursor,
/// When selecting with a mouse, this is where the mouse was first pressed.
/// This part of the cursor does not move when shift is down.
pub secondary: Cursor,
}
impl CursorPair {
fn one(cursor: Cursor) -> Self {
Self {
primary: cursor,
secondary: cursor,
}
}
fn two(min: Cursor, max: Cursor) -> Self {
Self {
primary: max,
secondary: min,
}
}
fn as_ccursorp(&self) -> CCursorPair {
CCursorPair {
primary: self.primary.ccursor,
secondary: self.secondary.ccursor,
}
}
fn is_empty(&self) -> bool {
self.primary.ccursor == self.secondary.ccursor
}
/// If there is a selection, None is returned.
/// If the two ends is the same, that is returned.
fn single(&self) -> Option<Cursor> {
if self.is_empty() {
Some(self.primary)
} else {
None
}
}
fn primary_is_first(&self) -> bool {
let p = self.primary.ccursor;
let s = self.secondary.ccursor;
(p.index, p.prefer_next_row) <= (s.index, s.prefer_next_row)
}
fn sorted(&self) -> [Cursor; 2] {
if self.primary_is_first() {
[self.primary, self.secondary]
} else {
[self.secondary, self.primary]
}
}
}
#[derive(Clone, Copy, Debug, Default, PartialEq)]
#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
struct CCursorPair {
/// When selecting with a mouse, this is where the mouse was released.
/// When moving with e.g. shift+arrows, this is what moves.
/// Note that the two ends can come in any order, and also be equal (no selection).
pub primary: CCursor,
/// When selecting with a mouse, this is where the mouse was first pressed.
/// This part of the cursor does not move when shift is down.
pub secondary: CCursor,
}
impl CCursorPair {
fn one(ccursor: CCursor) -> Self {
Self {
primary: ccursor,
secondary: ccursor,
}
}
fn two(min: CCursor, max: CCursor) -> Self {
Self {
primary: max,
secondary: min,
}
}
}
/// Trait constraining what types [`TextEdit`] may use as
/// an underlying buffer.
///
/// Most likely you will use a `String` which implements `TextBuffer`.
pub trait TextBuffer: AsRef<str> {
/// Can this text be edited?
fn is_mutable(&self) -> bool;
/// Inserts text `text` into this buffer at character index `ch_idx`.
///
/// # Notes
/// `ch_idx` is a *character index*, not a byte index.
///
/// # Return
/// Returns how many *characters* were successfully inserted
fn insert_text(&mut self, text: &str, ch_idx: usize) -> usize;
/// Deletes a range of text `ch_range` from this buffer.
///
/// # Notes
/// `ch_range` is a *character range*, not a byte range.
fn delete_char_range(&mut self, ch_range: Range<usize>);
/// Returns this buffer as a `str`.
///
/// This is an utility method, as it simply relies on the `AsRef<str>`
/// implementation.
fn as_str(&self) -> &str {
self.as_ref()
}
/// Clears all characters in this buffer
fn clear(&mut self) {
self.delete_char_range(0..self.as_ref().len());
}
/// Replaces all contents of this string with `text`
fn replace(&mut self, text: &str) {
self.clear();
self.insert_text(text, 0);
}
/// Clears all characters in this buffer and returns a string of the contents.
fn take(&mut self) -> String {
let s = self.as_ref().to_owned();
self.clear();
s
}
}
impl TextBuffer for String {
fn is_mutable(&self) -> bool {
true
}
fn insert_text(&mut self, text: &str, ch_idx: usize) -> usize {
// Get the byte index from the character index
let byte_idx = self::byte_index_from_char_index(self, ch_idx);
// Then insert the string
self.insert_str(byte_idx, text);
text.chars().count()
}
fn delete_char_range(&mut self, ch_range: Range<usize>) {
assert!(ch_range.start <= ch_range.end);
// Get both byte indices
let byte_start = self::byte_index_from_char_index(self, ch_range.start);
let byte_end = self::byte_index_from_char_index(self, ch_range.end);
// Then drain all characters within this range
self.drain(byte_start..byte_end);
}
fn clear(&mut self) {
self.clear();
}
fn replace(&mut self, text: &str) {
*self = text.to_owned();
}
fn take(&mut self) -> String {
std::mem::take(self)
}
}
/// Immutable view of a &str!
impl<'a> TextBuffer for &'a str {
fn is_mutable(&self) -> bool {
false
}
fn insert_text(&mut self, _text: &str, _ch_idx: usize) -> usize {
0
}
fn delete_char_range(&mut self, _ch_range: Range<usize>) {}
}
/// A text region that the user can edit the contents of.
///
/// See also [`Ui::text_edit_singleline`] and [`Ui::text_edit_multiline`].
///
/// Example:
///
/// ```
/// # let mut ui = egui::Ui::__test();
/// # let mut my_string = String::new();
/// let response = ui.add(egui::TextEdit::singleline(&mut my_string));
/// if response.changed() {
/// // …
/// }
/// if response.lost_focus() && ui.input().key_pressed(egui::Key::Enter) {
/// // …
/// }
/// ```
///
/// To fill an [`Ui`] with a [`TextEdit`] use [`Ui::add_sized`]:
///
/// ```
/// # let mut ui = egui::Ui::__test();
/// # let mut my_string = String::new();
/// ui.add_sized(ui.available_size(), egui::TextEdit::multiline(&mut my_string));
/// ```
///
///
/// You can also use [`TextEdit`] to show text that can be selected, but not edited.
/// To do so, pass in a `&mut` reference to a `&str`, for instance:
///
/// ```
/// fn selectable_text(ui: &mut egui::Ui, mut text: &str) {
/// ui.add(egui::TextEdit::multiline(&mut text));
/// }
/// ```
///
#[must_use = "You should put this widget in an ui with `ui.add(widget);`"]
pub struct TextEdit<'t> {
text: &'t mut dyn TextBuffer,
hint_text: String,
id: Option<Id>,
id_source: Option<Id>,
text_style: Option<TextStyle>,
text_color: Option<Color32>,
layouter: Option<&'t mut dyn FnMut(&Ui, &str, f32) -> Arc<Galley>>,
password: bool,
frame: bool,
multiline: bool,
interactive: bool,
desired_width: Option<f32>,
desired_height_rows: usize,
lock_focus: bool,
cursor_at_end: bool,
}
impl<'t> TextEdit<'t> {
/// No newlines (`\n`) allowed. Pressing enter key will result in the `TextEdit` losing focus (`response.lost_focus`).
pub fn singleline(text: &'t mut dyn TextBuffer) -> Self {
Self {
desired_height_rows: 1,
multiline: false,
..Self::multiline(text)
}
}
/// A `TextEdit` for multiple lines. Pressing enter key will create a new line.
pub fn multiline(text: &'t mut dyn TextBuffer) -> Self {
Self {
text,
hint_text: Default::default(),
id: None,
id_source: None,
text_style: None,
text_color: None,
layouter: None,
password: false,
frame: true,
multiline: true,
interactive: true,
desired_width: None,
desired_height_rows: 4,
lock_focus: false,
cursor_at_end: true,
}
}
/// Build a `TextEdit` focused on code editing.
/// By default it comes with:
/// - monospaced font
/// - focus lock
pub fn code_editor(self) -> Self {
self.text_style(TextStyle::Monospace).lock_focus(true)
}
/// Use if you want to set an explicit `Id` for this widget.
pub fn id(mut self, id: Id) -> Self {
self.id = Some(id);
self
}
/// A source for the unique `Id`, e.g. `.id_source("second_text_edit_field")` or `.id_source(loop_index)`.
pub fn id_source(mut self, id_source: impl std::hash::Hash) -> Self {
self.id_source = Some(Id::new(id_source));
self
}
/// Show a faint hint text when the text field is empty.
#[allow(clippy::needless_pass_by_value)]
pub fn hint_text(mut self, hint_text: impl ToString) -> Self {
self.hint_text = hint_text.to_string();
self
}
/// If true, hide the letters from view and prevent copying from the field.
pub fn password(mut self, password: bool) -> Self {
self.password = password;
self
}
pub fn text_style(mut self, text_style: TextStyle) -> Self {
self.text_style = Some(text_style);
self
}
pub fn text_color(mut self, text_color: Color32) -> Self {
self.text_color = Some(text_color);
self
}
pub fn text_color_opt(mut self, text_color: Option<Color32>) -> Self {
self.text_color = text_color;
self
}
/// Override how text is being shown inside the `TextEdit`.
///
/// This can be used to implement things like syntax highlighting.
///
/// This function will be called at least once per frame,
/// so it is strongly suggested that you cache the results of any syntax highlighter
/// so as not to waste CPU highlighting the same string every frame.
///
/// The arguments is the enclosing [`Ui`] (so you can access e.g. [`Ui::fonts`]),
/// the text and the wrap width.
///
/// ```
/// # let ui = &mut egui::Ui::__test();
/// # let mut my_code = String::new();
/// # fn my_memoized_highlighter(s: &str) -> egui::text::LayoutJob { Default::default() }
/// let mut layouter = |ui: &egui::Ui, string: &str, wrap_width: f32| {
/// let mut layout_job: egui::text::LayoutJob = my_memoized_highlighter(string);
/// layout_job.wrap_width = wrap_width;
/// ui.fonts().layout_job(layout_job)
/// };
/// ui.add(egui::TextEdit::multiline(&mut my_code).layouter(&mut layouter));
/// ```
pub fn layouter(mut self, layouter: &'t mut dyn FnMut(&Ui, &str, f32) -> Arc<Galley>) -> Self {
self.layouter = Some(layouter);
self
}
/// Default is `true`. If set to `false` then you cannot interact with the text (neither edit or select it).
///
/// Consider using [`Ui::add_enabled`] instead to also give the `TextEdit` a greyed out look.
pub fn interactive(mut self, interactive: bool) -> Self {
self.interactive = interactive;
self
}
#[deprecated = "Use TextEdit::interactive or ui.add_enabled instead"]
pub fn enabled(self, enabled: bool) -> Self {
self.interactive(enabled)
}
/// Default is `true`. If set to `false` there will be no frame showing that this is editable text!
pub fn frame(mut self, frame: bool) -> Self {
self.frame = frame;
self
}
/// Set to 0.0 to keep as small as possible.
/// Set to [`f32::INFINITY`] to take up all available space (i.e. disable automatic word wrap).
pub fn desired_width(mut self, desired_width: f32) -> Self {
self.desired_width = Some(desired_width);
self
}
/// Set the number of rows to show by default.
/// The default for singleline text is `1`.
/// The default for multiline text is `4`.
pub fn desired_rows(mut self, desired_height_rows: usize) -> Self {
self.desired_height_rows = desired_height_rows;
self
}
/// When `false` (default), pressing TAB will move focus
/// to the next widget.
///
/// When `true`, the widget will keep the focus and pressing TAB
/// will insert the `'\t'` character.
pub fn lock_focus(mut self, b: bool) -> Self {
self.lock_focus = b;
self
}
/// When `true` (default), the cursor will initially be placed at the end of the text.
///
/// When `false`, the cursor will initially be placed at the beginning of the text.
pub fn cursor_at_end(mut self, b: bool) -> Self {
self.cursor_at_end = b;
self
}
}
impl<'t> TextEdit<'t> {
pub fn cursor(ui: &Ui, id: Id) -> Option<CursorPair> {
ui.memory()
.id_data
.get::<State>(&id)
.and_then(|state| state.cursorp)
}
}
impl<'t> Widget for TextEdit<'t> {
fn ui(self, ui: &mut Ui) -> Response {
let is_mutable = self.text.is_mutable();
let frame = self.frame;
let interactive = self.interactive;
let where_to_put_background = ui.painter().add(Shape::Noop);
let margin = Vec2::new(4.0, 2.0);
let max_rect = ui.available_rect_before_wrap().shrink2(margin);
let mut content_ui = ui.child_ui(max_rect, *ui.layout());
let mut response = self.content_ui(&mut content_ui);
let id = response.id;
let frame_rect = response.rect.expand2(margin);
ui.allocate_space(frame_rect.size());
if interactive {
response |= ui.interact(frame_rect, id, Sense::click());
}
if response.clicked() && !response.lost_focus() {
ui.memory().request_focus(response.id);
}
if frame {
let visuals = ui.style().interact(&response);
let frame_rect = frame_rect.expand(visuals.expansion);
let shape = if is_mutable {
if response.has_focus() {
epaint::RectShape {
rect: frame_rect,
corner_radius: visuals.corner_radius,
// fill: ui.visuals().selection.bg_fill,
fill: ui.visuals().extreme_bg_color,
stroke: ui.visuals().selection.stroke,
}
} else {
epaint::RectShape {
rect: frame_rect,
corner_radius: visuals.corner_radius,
fill: ui.visuals().extreme_bg_color,
stroke: visuals.bg_stroke, // TODO: we want to show something here, or a text-edit field doesn't "pop".
}
}
} else {
let visuals = &ui.style().visuals.widgets.inactive;
epaint::RectShape {
rect: frame_rect,
corner_radius: visuals.corner_radius,
// fill: ui.visuals().extreme_bg_color,
// fill: visuals.bg_fill,
fill: Color32::TRANSPARENT,
stroke: visuals.bg_stroke, // TODO: we want to show something here, or a text-edit field doesn't "pop".
}
};
ui.painter().set(where_to_put_background, shape);
}
response
}
}
fn mask_massword(text: &str) -> String {
std::iter::repeat(epaint::text::PASSWORD_REPLACEMENT_CHAR)
.take(text.chars().count())
.collect::<String>()
}
fn mask_if_password(is_password: bool, text: &str) -> String {
if is_password {
mask_massword(text)
} else {
text.to_owned()
}
}
impl<'t> TextEdit<'t> {
fn content_ui(self, ui: &mut Ui) -> Response {
let TextEdit {
text,
hint_text,
id,
id_source,
text_style,
text_color,
layouter,
password,
frame: _,
multiline,
interactive,
desired_width,
desired_height_rows,
lock_focus,
cursor_at_end,
} = self;
let text_color = text_color
.or(ui.visuals().override_text_color)
// .unwrap_or_else(|| ui.style().interact(&response).text_color()); // too bright
.unwrap_or_else(|| ui.visuals().widgets.inactive.text_color());
let prev_text = text.as_ref().to_owned();
let text_style = text_style
.or(ui.style().override_text_style)
.unwrap_or_else(|| ui.style().body_text_style);
let row_height = ui.fonts().row_height(text_style);
const MIN_WIDTH: f32 = 24.0; // Never make a `TextEdit` more narrow than this.
let available_width = ui.available_width().at_least(MIN_WIDTH);
let desired_width = desired_width.unwrap_or_else(|| ui.spacing().text_edit_width);
let wrap_width = if ui.layout().horizontal_justify() {
available_width
} else {
desired_width.min(available_width)
};
let mut default_layouter = move |ui: &Ui, text: &str, wrap_width: f32| {
let text = mask_if_password(password, text);
ui.fonts().layout_job(if multiline {
LayoutJob::simple(text, text_style, text_color, wrap_width)
} else {
LayoutJob::simple_singleline(text, text_style, text_color)
})
};
let layouter = layouter.unwrap_or(&mut default_layouter);
let copy_if_not_password = |ui: &Ui, text: String| {
if !password {
ui.ctx().output().copied_text = text;
}
};
let mut galley = layouter(ui, text.as_ref(), wrap_width);
let desired_width = if multiline {
galley.size().x.max(wrap_width) // always show everything in multiline
} else {
wrap_width // visual clipping with scroll in singleline input. TODO: opt-in/out?
};
let desired_height = (desired_height_rows.at_least(1) as f32) * row_height;
let desired_size = vec2(desired_width, galley.size().y.max(desired_height));
let (auto_id, rect) = ui.allocate_space(desired_size);
let id = id.unwrap_or_else(|| {
if let Some(id_source) = id_source {
ui.make_persistent_id(id_source)
} else {
auto_id // Since we are only storing the cursor a persistent Id is not super important
}
});
let mut state = ui.memory().id_data.get_or_default::<State>(id).clone();
let sense = if interactive {
Sense::click_and_drag()
} else {
Sense::hover()
};
let mut response = ui.interact(rect, id, sense);
let painter = ui.painter_at(rect);
if interactive {
if let Some(pointer_pos) = ui.input().pointer.interact_pos() {
// TODO: triple-click to select whole paragraph
// TODO: drag selected text to either move or clone (ctrl on windows, alt on mac)
let singleline_offset = vec2(state.singleline_offset, 0.0);
let cursor_at_pointer =
galley.cursor_from_pos(pointer_pos - response.rect.min + singleline_offset);
if ui.visuals().text_cursor_preview
&& response.hovered()
&& ui.input().pointer.is_moving()
{
// preview:
paint_cursor_end(
ui,
row_height,
&painter,
response.rect.min,
&galley,
&cursor_at_pointer,
);
}
if response.double_clicked() {
// Select word:
let center = cursor_at_pointer;
let ccursorp = select_word_at(text.as_ref(), center.ccursor);
state.cursorp = Some(CursorPair {
primary: galley.from_ccursor(ccursorp.primary),
secondary: galley.from_ccursor(ccursorp.secondary),
});
} else if response.hovered() && ui.input().pointer.any_pressed() {
ui.memory().request_focus(id);
if ui.input().modifiers.shift {
if let Some(cursorp) = &mut state.cursorp {
cursorp.primary = cursor_at_pointer;
} else {
state.cursorp = Some(CursorPair::one(cursor_at_pointer));
}
} else {
state.cursorp = Some(CursorPair::one(cursor_at_pointer));
}
} else if ui.input().pointer.any_down() && response.is_pointer_button_down_on() {
if let Some(cursorp) = &mut state.cursorp {
cursorp.primary = cursor_at_pointer;
}
}
}
}
if response.hovered() && interactive {
ui.output().cursor_icon = CursorIcon::Text;
}
let mut text_cursor = None;
let prev_text_cursor = state.cursorp;
if ui.memory().has_focus(id) && interactive {
ui.memory().lock_focus(id, lock_focus);
let mut cursorp = state.cursorp.map_or_else(
|| {
if cursor_at_end {
CursorPair::one(galley.end())
} else {
CursorPair::default()
}
},
|cursorp| {
// We only keep the PCursor (paragraph number, and character offset within that paragraph).
// This is so what if we resize the `TextEdit` region, and text wrapping changes,
// we keep the same byte character offset from the beginning of the text,
// even though the number of rows changes
// (each paragraph can be several rows, due to word wrapping).
// The column (character offset) should be able to extend beyond the last word so that we can
// go down and still end up on the same column when we return.
CursorPair {
primary: galley.from_pcursor(cursorp.primary.pcursor),
secondary: galley.from_pcursor(cursorp.secondary.pcursor),
}
},
);
// We feed state to the undoer both before and after handling input
// so that the undoer creates automatic saves even when there are no events for a while.
state.undoer.feed_state(
ui.input().time,
&(cursorp.as_ccursorp(), text.as_ref().to_owned()),
);
for event in &ui.input().events {
let did_mutate_text = match event {
Event::Copy => {
if cursorp.is_empty() {
copy_if_not_password(ui, text.as_ref().to_owned());
} else {
copy_if_not_password(
ui,
selected_str(text.as_ref(), &cursorp).to_owned(),
);
}
None
}
Event::Cut => {
if cursorp.is_empty() {
copy_if_not_password(ui, text.take());
Some(CCursorPair::default())
} else {
copy_if_not_password(
ui,
selected_str(text.as_ref(), &cursorp).to_owned(),
);
Some(CCursorPair::one(delete_selected(text, &cursorp)))
}
}
Event::Text(text_to_insert) => {
// Newlines are handled by `Key::Enter`.
if !text_to_insert.is_empty()
&& text_to_insert != "\n"
&& text_to_insert != "\r"
{
let mut ccursor = delete_selected(text, &cursorp);
insert_text(&mut ccursor, text, text_to_insert);
Some(CCursorPair::one(ccursor))
} else {
None
}
}
Event::Key {
key: Key::Tab,
pressed: true,
modifiers,
} => {
if multiline && ui.memory().has_lock_focus(id) {
let mut ccursor = delete_selected(text, &cursorp);
if modifiers.shift {
// TODO: support removing indentation over a selection?
decrease_identation(&mut ccursor, text);
} else {
insert_text(&mut ccursor, text, "\t");
}
Some(CCursorPair::one(ccursor))
} else {
None
}
}
Event::Key {
key: Key::Enter,
pressed: true,
..
} => {
if multiline {
let mut ccursor = delete_selected(text, &cursorp);
insert_text(&mut ccursor, text, "\n");
Some(CCursorPair::one(ccursor))
} else {
ui.memory().surrender_focus(id); // End input with enter
break;
}
}
Event::Key {
key: Key::Z,
pressed: true,
modifiers,
} if modifiers.command && !modifiers.shift => {
// TODO: redo
if let Some((undo_ccursorp, undo_txt)) = state
.undoer
.undo(&(cursorp.as_ccursorp(), text.as_ref().to_owned()))
{
text.replace(undo_txt);
Some(*undo_ccursorp)
} else {
None
}
}
Event::Key {
key,
pressed: true,
modifiers,
} => on_key_press(&mut cursorp, text, &galley, *key, modifiers),
Event::CompositionStart => {
state.has_ime = true;
None
}
Event::CompositionUpdate(text_mark) => {
if !text_mark.is_empty()
&& text_mark != "\n"
&& text_mark != "\r"
&& state.has_ime
{
let mut ccursor = delete_selected(text, &cursorp);
let start_cursor = ccursor;
insert_text(&mut ccursor, text, text_mark);
Some(CCursorPair::two(start_cursor, ccursor))
} else {
None
}
}
Event::CompositionEnd(prediction) => {
if !prediction.is_empty()
&& prediction != "\n"
&& prediction != "\r"
&& state.has_ime
{
state.has_ime = false;
let mut ccursor = delete_selected(text, &cursorp);
insert_text(&mut ccursor, text, prediction);
Some(CCursorPair::one(ccursor))
} else {
None
}
}
_ => None,
};
if let Some(new_ccursorp) = did_mutate_text {
response.mark_changed();
// Layout again to avoid frame delay, and to keep `text` and `galley` in sync.
galley = layouter(ui, text.as_ref(), wrap_width);
// Set cursorp using new galley:
cursorp = CursorPair {
primary: galley.from_ccursor(new_ccursorp.primary),
secondary: galley.from_ccursor(new_ccursorp.secondary),
};
}
}
state.cursorp = Some(cursorp);
text_cursor = Some(cursorp);
state.undoer.feed_state(
ui.input().time,
&(cursorp.as_ccursorp(), text.as_ref().to_owned()),
);
}
let mut text_draw_pos = response.rect.min;
// Visual clipping for singleline text editor with text larger than width
if !multiline {
let cursor_pos = match (state.cursorp, ui.memory().has_focus(id)) {
(Some(cursorp), true) => galley.pos_from_cursor(&cursorp.primary).min.x,
_ => 0.0,
};
let mut offset_x = state.singleline_offset;
let visible_range = offset_x..=offset_x + desired_size.x;
if !visible_range.contains(&cursor_pos) {
if cursor_pos < *visible_range.start() {
offset_x = cursor_pos;
} else {
offset_x = cursor_pos - desired_size.x;
}
}
offset_x = offset_x
.at_most(galley.size().x - desired_size.x)
.at_least(0.0);
state.singleline_offset = offset_x;
text_draw_pos -= vec2(offset_x, 0.0);
}
painter.galley(text_draw_pos, galley.clone());
if text.as_ref().is_empty() && !hint_text.is_empty() {
let hint_text_color = ui.visuals().weak_text_color();
let galley = ui.fonts().layout_job(if multiline {
LayoutJob::simple(hint_text, text_style, hint_text_color, desired_size.x)
} else {
LayoutJob::simple_singleline(hint_text, text_style, hint_text_color)
});
painter.galley(response.rect.min, galley);
}
if ui.memory().has_focus(id) {
if let Some(cursorp) = state.cursorp {
// We paint the cursor on top of the text, in case
// the text galley has backgrounds (as e.g. `code` snippets in markup do).
paint_cursor_selection(ui, &painter, text_draw_pos, &galley, &cursorp);
paint_cursor_end(
ui,
row_height,
&painter,
text_draw_pos,
&galley,
&cursorp.primary,
);
if interactive {
ui.ctx().output().text_cursor_pos = Some(
galley
.pos_from_cursor(&cursorp.primary)
.translate(response.rect.min.to_vec2())
.left_top(),
);
}
}
}
ui.memory().id_data.insert(id, state);
let selection_changed = if let (Some(text_cursor), Some(prev_text_cursor)) =
(text_cursor, prev_text_cursor)
{
text_cursor.primary.ccursor.index != prev_text_cursor.primary.ccursor.index
|| text_cursor.secondary.ccursor.index != prev_text_cursor.secondary.ccursor.index
} else {
false
};
if response.changed {
response.widget_info(|| {
WidgetInfo::text_edit(
mask_if_password(password, prev_text.as_str()),
mask_if_password(password, text.as_str()),
)
});
} else if selection_changed {
let text_cursor = text_cursor.unwrap();
let char_range =
text_cursor.primary.ccursor.index..=text_cursor.secondary.ccursor.index;
let info = WidgetInfo::text_selection_changed(
char_range,
mask_if_password(password, text.as_str()),
);
response
.ctx
.output()
.events
.push(OutputEvent::TextSelectionChanged(info));
} else {
response.widget_info(|| {
WidgetInfo::text_edit(
mask_if_password(password, prev_text.as_str()),
mask_if_password(password, text.as_str()),
)
});
}
response
}
}
// ----------------------------------------------------------------------------
fn paint_cursor_selection(
ui: &mut Ui,
painter: &Painter,
pos: Pos2,
galley: &Galley,
cursorp: &CursorPair,
) {
if cursorp.is_empty() {
return;
}
// We paint the cursor selection on top of the text, so make it transparent:
let color = ui.visuals().selection.bg_fill.linear_multiply(0.5);
let [min, max] = cursorp.sorted();
let min = min.rcursor;
let max = max.rcursor;
for ri in min.row..=max.row {
let row = &galley.rows[ri];
let left = if ri == min.row {
row.x_offset(min.column)
} else {
row.rect.left()
};
let right = if ri == max.row {
row.x_offset(max.column)
} else {
let newline_size = if row.ends_with_newline {
row.height() / 2.0 // visualize that we select the newline
} else {
0.0
};
row.rect.right() + newline_size
};
let rect = Rect::from_min_max(
pos + vec2(left, row.min_y()),
pos + vec2(right, row.max_y()),
);
painter.rect_filled(rect, 0.0, color);
}
}
fn paint_cursor_end(
ui: &mut Ui,
row_height: f32,
painter: &Painter,
pos: Pos2,
galley: &Galley,
cursor: &Cursor,
) {
let stroke = ui.visuals().selection.stroke;
let mut cursor_pos = galley.pos_from_cursor(cursor).translate(pos.to_vec2());
cursor_pos.max.y = cursor_pos.max.y.at_least(cursor_pos.min.y + row_height); // Handle completely empty galleys
cursor_pos = cursor_pos.expand(1.5); // slightly above/below row
let top = cursor_pos.center_top();
let bottom = cursor_pos.center_bottom();
painter.line_segment(
[top, bottom],
(ui.visuals().text_cursor_width, stroke.color),
);
if false {
// Roof/floor:
let extrusion = 3.0;
let width = 1.0;
painter.line_segment(
[top - vec2(extrusion, 0.0), top + vec2(extrusion, 0.0)],
(width, stroke.color),
);
painter.line_segment(
[bottom - vec2(extrusion, 0.0), bottom + vec2(extrusion, 0.0)],
(width, stroke.color),
);
}
}
// ----------------------------------------------------------------------------
fn selected_str<'s>(text: &'s str, cursorp: &CursorPair) -> &'s str {
let [min, max] = cursorp.sorted();
let byte_begin = byte_index_from_char_index(text, min.ccursor.index);
let byte_end = byte_index_from_char_index(text, max.ccursor.index);
&text[byte_begin..byte_end]
}
fn byte_index_from_char_index(s: &str, char_index: usize) -> usize {
for (ci, (bi, _)) in s.char_indices().enumerate() {
if ci == char_index {
return bi;
}
}
s.len()
}
fn insert_text(ccursor: &mut CCursor, text: &mut dyn TextBuffer, text_to_insert: &str) {
ccursor.index += text.insert_text(text_to_insert, ccursor.index);
}
// ----------------------------------------------------------------------------
fn delete_selected(text: &mut dyn TextBuffer, cursorp: &CursorPair) -> CCursor {
let [min, max] = cursorp.sorted();
delete_selected_ccursor_range(text, [min.ccursor, max.ccursor])
}
fn delete_selected_ccursor_range(text: &mut dyn TextBuffer, [min, max]: [CCursor; 2]) -> CCursor {
text.delete_char_range(min.index..max.index);
CCursor {
index: min.index,
prefer_next_row: true,
}
}
fn delete_previous_char(text: &mut dyn TextBuffer, ccursor: CCursor) -> CCursor {
if ccursor.index > 0 {
let max_ccursor = ccursor;
let min_ccursor = max_ccursor - 1;
delete_selected_ccursor_range(text, [min_ccursor, max_ccursor])
} else {
ccursor
}
}
fn delete_next_char(text: &mut dyn TextBuffer, ccursor: CCursor) -> CCursor {
delete_selected_ccursor_range(text, [ccursor, ccursor + 1])
}
fn delete_previous_word(text: &mut dyn TextBuffer, max_ccursor: CCursor) -> CCursor {
let min_ccursor = ccursor_previous_word(text.as_ref(), max_ccursor);
delete_selected_ccursor_range(text, [min_ccursor, max_ccursor])
}
fn delete_next_word(text: &mut dyn TextBuffer, min_ccursor: CCursor) -> CCursor {
let max_ccursor = ccursor_next_word(text.as_ref(), min_ccursor);
delete_selected_ccursor_range(text, [min_ccursor, max_ccursor])
}
fn delete_paragraph_before_cursor(
text: &mut dyn TextBuffer,
galley: &Galley,
cursorp: &CursorPair,
) -> CCursor {
let [min, max] = cursorp.sorted();
let min = galley.from_pcursor(PCursor {
paragraph: min.pcursor.paragraph,
offset: 0,
prefer_next_row: true,
});
if min.ccursor == max.ccursor {
delete_previous_char(text, min.ccursor)
} else {
delete_selected(text, &CursorPair::two(min, max))
}
}
fn delete_paragraph_after_cursor(
text: &mut dyn TextBuffer,
galley: &Galley,
cursorp: &CursorPair,
) -> CCursor {
let [min, max] = cursorp.sorted();
let max = galley.from_pcursor(PCursor {
paragraph: max.pcursor.paragraph,
offset: usize::MAX, // end of paragraph
prefer_next_row: false,
});
if min.ccursor == max.ccursor {
delete_next_char(text, min.ccursor)
} else {
delete_selected(text, &CursorPair::two(min, max))
}
}
// ----------------------------------------------------------------------------
/// Returns `Some(new_cursor)` if we did mutate `text`.
fn on_key_press(
cursorp: &mut CursorPair,
text: &mut dyn TextBuffer,
galley: &Galley,
key: Key,
modifiers: &Modifiers,
) -> Option<CCursorPair> {
match key {
Key::Backspace => {
let ccursor = if modifiers.mac_cmd {
delete_paragraph_before_cursor(text, galley, cursorp)
} else if let Some(cursor) = cursorp.single() {
if modifiers.alt || modifiers.ctrl {
// alt on mac, ctrl on windows
delete_previous_word(text, cursor.ccursor)
} else {
delete_previous_char(text, cursor.ccursor)
}
} else {
delete_selected(text, cursorp)
};
Some(CCursorPair::one(ccursor))
}
Key::Delete if !(cfg!(target_os = "windows") && modifiers.shift) => {
let ccursor = if modifiers.mac_cmd {
delete_paragraph_after_cursor(text, galley, cursorp)
} else if let Some(cursor) = cursorp.single() {
if modifiers.alt || modifiers.ctrl {
// alt on mac, ctrl on windows
delete_next_word(text, cursor.ccursor)
} else {
delete_next_char(text, cursor.ccursor)
}
} else {
delete_selected(text, cursorp)
};
let ccursor = CCursor {
prefer_next_row: true,
..ccursor
};
Some(CCursorPair::one(ccursor))
}
Key::A if modifiers.command => {
// select all
*cursorp = CursorPair::two(Cursor::default(), galley.end());
None
}
Key::K if modifiers.ctrl => {
let ccursor = delete_paragraph_after_cursor(text, galley, cursorp);
Some(CCursorPair::one(ccursor))
}
Key::U if modifiers.ctrl => {
let ccursor = delete_paragraph_before_cursor(text, galley, cursorp);
Some(CCursorPair::one(ccursor))
}
Key::W if modifiers.ctrl => {
let ccursor = if let Some(cursor) = cursorp.single() {
delete_previous_word(text, cursor.ccursor)
} else {
delete_selected(text, cursorp)
};
Some(CCursorPair::one(ccursor))
}
Key::ArrowLeft | Key::ArrowRight if modifiers.is_none() && !cursorp.is_empty() => {
if key == Key::ArrowLeft {
*cursorp = CursorPair::one(cursorp.sorted()[0]);
} else {
*cursorp = CursorPair::one(cursorp.sorted()[1]);
}
None
}
Key::ArrowLeft | Key::ArrowRight | Key::ArrowUp | Key::ArrowDown | Key::Home | Key::End => {
move_single_cursor(&mut cursorp.primary, galley, key, modifiers);
if !modifiers.shift {
cursorp.secondary = cursorp.primary;
}
None
}
_ => None,
}
}
fn move_single_cursor(cursor: &mut Cursor, galley: &Galley, key: Key, modifiers: &Modifiers) {
match key {
Key::ArrowLeft => {
if modifiers.alt || modifiers.ctrl {
// alt on mac, ctrl on windows
*cursor = galley.from_ccursor(ccursor_previous_word(galley.text(), cursor.ccursor));
} else if modifiers.mac_cmd {
*cursor = galley.cursor_begin_of_row(cursor);
} else {
*cursor = galley.cursor_left_one_character(cursor);
}
}
Key::ArrowRight => {
if modifiers.alt || modifiers.ctrl {
// alt on mac, ctrl on windows
*cursor = galley.from_ccursor(ccursor_next_word(galley.text(), cursor.ccursor));
} else if modifiers.mac_cmd {
*cursor = galley.cursor_end_of_row(cursor);
} else {
*cursor = galley.cursor_right_one_character(cursor);
}
}
Key::ArrowUp => {
if modifiers.command {
// mac and windows behavior
*cursor = Cursor::default();
} else {
*cursor = galley.cursor_up_one_row(cursor);
}
}
Key::ArrowDown => {
if modifiers.command {
// mac and windows behavior
*cursor = galley.end();
} else {
*cursor = galley.cursor_down_one_row(cursor);
}
}
Key::Home => {
if modifiers.ctrl {
// windows behavior
*cursor = Cursor::default();
} else {
*cursor = galley.cursor_begin_of_row(cursor);
}
}
Key::End => {
if modifiers.ctrl {
// windows behavior
*cursor = galley.end();
} else {
*cursor = galley.cursor_end_of_row(cursor);
}
}
_ => unreachable!(),
}
}
// ----------------------------------------------------------------------------
fn select_word_at(text: &str, ccursor: CCursor) -> CCursorPair {
if ccursor.index == 0 {
CCursorPair::two(ccursor, ccursor_next_word(text, ccursor))
} else {
let it = text.chars();
let mut it = it.skip(ccursor.index - 1);
if let Some(char_before_cursor) = it.next() {
if let Some(char_after_cursor) = it.next() {
if is_word_char(char_before_cursor) && is_word_char(char_after_cursor) {
let min = ccursor_previous_word(text, ccursor + 1);
let max = ccursor_next_word(text, min);
CCursorPair::two(min, max)
} else if is_word_char(char_before_cursor) {
let min = ccursor_previous_word(text, ccursor);
let max = ccursor_next_word(text, min);
CCursorPair::two(min, max)
} else if is_word_char(char_after_cursor) {
let max = ccursor_next_word(text, ccursor);
CCursorPair::two(ccursor, max)
} else {
let min = ccursor_previous_word(text, ccursor);
let max = ccursor_next_word(text, ccursor);
CCursorPair::two(min, max)
}
} else {
let min = ccursor_previous_word(text, ccursor);
CCursorPair::two(min, ccursor)
}
} else {
let max = ccursor_next_word(text, ccursor);
CCursorPair::two(ccursor, max)
}
}
}
fn ccursor_next_word(text: &str, ccursor: CCursor) -> CCursor {
CCursor {
index: next_word_boundary_char_index(text.chars(), ccursor.index),
prefer_next_row: false,
}
}
fn ccursor_previous_word(text: &str, ccursor: CCursor) -> CCursor {
let num_chars = text.chars().count();
CCursor {
index: num_chars
- next_word_boundary_char_index(text.chars().rev(), num_chars - ccursor.index),
prefer_next_row: true,
}
}
fn next_word_boundary_char_index(it: impl Iterator<Item = char>, mut index: usize) -> usize {
let mut it = it.skip(index);
if let Some(_first) = it.next() {
index += 1;
if let Some(second) = it.next() {
index += 1;
for next in it {
if is_word_char(next) != is_word_char(second) {
break;
}
index += 1;
}
}
}
index
}
fn is_word_char(c: char) -> bool {
c.is_ascii_alphanumeric() || c == '_'
}
/// Accepts and returns character offset (NOT byte offset!).
fn find_line_start(text: &str, current_index: CCursor) -> CCursor {
// We know that new lines, '\n', are a single byte char, but we have to
// work with char offsets because before the new line there may be any
// number of multi byte chars.
// We need to know the char index to be able to correctly set the cursor
// later.
let chars_count = text.chars().count();
let position = text
.chars()
.rev()
.skip(chars_count - current_index.index)
.position(|x| x == '\n');
match position {
Some(pos) => CCursor::new(current_index.index - pos),
None => CCursor::new(0),
}
}
fn decrease_identation(ccursor: &mut CCursor, text: &mut dyn TextBuffer) {
let line_start = find_line_start(text.as_ref(), *ccursor);
let remove_len = if text.as_ref()[line_start.index..].starts_with('\t') {
Some(1)
} else if text.as_ref()[line_start.index..]
.chars()
.take(text::TAB_SIZE)
.all(|c| c == ' ')
{
Some(text::TAB_SIZE)
} else {
None
};
if let Some(len) = remove_len {
text.delete_char_range(line_start.index..(line_start.index + len));
if *ccursor != line_start {
*ccursor -= len;
}
}
}