migrations/egui
1
0
Fork 0
mirror of https://github.com/emilk/egui.git synced 2026-06-26 22:53:14 -04:00
Code Activity

Feat(eframe/web): add best-effort support for IME preedit visulas for browsers

Browse Source
This commit is contained in:
umajho
2026-04-09 17:28:50 +08:00
parent 4b35b97319
commit c1962de280
1 changed files with 48 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files

68
crates/eframe/src/web/text_agent.rs
View File

@@ -62,14 +62,56 @@ impl TextAgent {
input.blur().ok();
input.focus().ok();
}
// if `is_composing` is true, then user is using IME, for example: emoji, pinyin, kanji, hangul, etc.
// In that case, the browser emits both `input` and `compositionupdate` events,
// and we need to ignore the `input` event.
if !text.is_empty() && !event.is_composing() {
input.set_value("");
let event = egui::Event::Text(text);
if event.is_composing() {
// if `is_composing` is true, then user is using IME, for
// example: emoji, pinyin, kanji, hangul, etc. In that case,
// the browser emits both `input` and `compositionupdate`
// events.
// We handle the composition update here instead of in the
// `compositionupdate` event because the selection range
// has not yet been updated when `compositionupdate` fires.
let Some(text) = event.data() else { return };
let selection_start = input
.selection_start()
.unwrap_or(None)
.map(|pos| pos as usize);
let selection_end = input
.selection_end()
.unwrap_or(None)
.map(|pos| pos as usize);
let active_range_chars = if let Some(selection_start) = selection_start
&& let Some(selection_end) = selection_end
{
let text_utf16 = text.encode_utf16().collect::<Vec<u16>>();
let text_before_selection =
String::from_utf16_lossy(&text_utf16[..selection_start]);
let text_in_selection =
String::from_utf16_lossy(&text_utf16[selection_start..selection_end]);
let count_before_selection = text_before_selection.chars().count();
let count_in_selection = text_in_selection.chars().count();
Some(count_before_selection..count_before_selection + count_in_selection)
} else {
None
};
let event = egui::Event::Ime(egui::ImeEvent::Preedit {
text,
active_range_chars,
});
runner.input.raw.events.push(event);
runner.needs_repaint.repaint_asap();
} else {
if text.is_empty() {
return;
}
if !event.is_composing() {
input.set_value("");
let event = egui::Event::Text(text);
runner.input.raw.events.push(event);
runner.needs_repaint.repaint_asap();
}
}
}
};
@@ -82,19 +124,6 @@ impl TextAgent {
}
};
let on_composition_update = {
move |event: web_sys::CompositionEvent, runner: &mut AppRunner| {
let Some(text) = event.data() else { return };
let event = egui::Event::Ime(egui::ImeEvent::Preedit {
text,
// TODO(umajho): implement this.
active_range_chars: None,
});
runner.input.raw.events.push(event);
runner.needs_repaint.repaint_asap();
}
};
let on_composition_end = {
let input = input.clone();
move |event: web_sys::CompositionEvent, runner: &mut AppRunner| {
@@ -108,7 +137,6 @@ impl TextAgent {
runner_ref.add_event_listener(&input, "input", on_input)?;
runner_ref.add_event_listener(&input, "compositionstart", on_composition_start)?;
runner_ref.add_event_listener(&input, "compositionupdate", on_composition_update)?;
runner_ref.add_event_listener(&input, "compositionend", on_composition_end)?;
// The canvas doesn't get keydown/keyup events when the text agent is focused,