Files
oak-gpui/crates/gpui3/src/elements/text.rs
T
2023-10-17 08:26:12 +02:00

132 lines
3.7 KiB
Rust

use crate::{
AnyElement, BorrowWindow, Bounds, Element, IntoAnyElement, LayoutId, Line, Pixels,
SharedString, Size, ViewContext,
};
use parking_lot::Mutex;
use smallvec::SmallVec;
use std::{marker::PhantomData, sync::Arc};
use util::ResultExt;
impl<S: 'static + Send + Sync> IntoAnyElement<S> for SharedString {
fn into_any(self) -> AnyElement<S> {
Text {
text: self,
state_type: PhantomData,
}
.into_any()
}
}
impl<V: 'static + Send + Sync> IntoAnyElement<V> for &'static str {
fn into_any(self) -> AnyElement<V> {
Text {
text: self.into(),
state_type: PhantomData,
}
.into_any()
}
}
// TODO: Figure out how to pass `String` to `child` without this.
// This impl doesn't exist in the `gpui2` crate.
impl<S: 'static + Send + Sync> IntoAnyElement<S> for String {
fn into_any(self) -> AnyElement<S> {
Text {
text: self.into(),
state_type: PhantomData,
}
.into_any()
}
}
pub struct Text<S> {
text: SharedString,
state_type: PhantomData<S>,
}
impl<S: 'static + Send + Sync> IntoAnyElement<S> for Text<S> {
fn into_any(self) -> AnyElement<S> {
AnyElement::new(self)
}
}
impl<S: 'static + Send + Sync> Element for Text<S> {
type ViewState = S;
type ElementState = Arc<Mutex<Option<TextElementState>>>;
fn element_id(&self) -> Option<crate::ElementId> {
None
}
fn layout(
&mut self,
_view: &mut S,
_element_state: Option<Self::ElementState>,
cx: &mut ViewContext<S>,
) -> (LayoutId, Self::ElementState) {
let text_system = cx.text_system().clone();
let text_style = cx.text_style();
let font_size = text_style.font_size * cx.rem_size();
let line_height = text_style
.line_height
.to_pixels(font_size.into(), cx.rem_size());
let text = self.text.clone();
let element_state = Arc::new(Mutex::new(None));
let rem_size = cx.rem_size();
let layout_id = cx.request_measured_layout(Default::default(), rem_size, {
let element_state = element_state.clone();
move |known_dimensions, _| {
let Some(lines) = text_system
.layout_text(
&text,
font_size,
&[text_style.to_run(text.len())],
known_dimensions.width, // Wrap if we know the width.
)
.log_err()
else {
return Size::default();
};
let size = Size {
width: lines.iter().map(|line| line.layout.width).max().unwrap(),
height: line_height * lines.len(),
};
element_state
.lock()
.replace(TextElementState { lines, line_height });
size
}
});
(layout_id, element_state)
}
fn paint<'a>(
&mut self,
bounds: Bounds<Pixels>,
_: &mut Self::ViewState,
element_state: &mut Self::ElementState,
cx: &mut ViewContext<S>,
) {
let element_state = element_state.lock();
let element_state = element_state
.as_ref()
.expect("measurement has not been performed");
let line_height = element_state.line_height;
let mut line_origin = bounds.origin;
for line in &element_state.lines {
line.paint(line_origin, line_height, cx).log_err();
line_origin.y += line.size(line_height).height;
}
}
}
pub struct TextElementState {
lines: SmallVec<[Line; 1]>,
line_height: Pixels,
}