ZIm/crates/gpui2/src/elements/text.rs
2023-10-26 12:46:52 +02:00

145 lines
3.9 KiB
Rust

use crate::{
AnyElement, BorrowWindow, Bounds, Component, Element, LayoutId, Line, Pixels, SharedString,
Size, ViewContext,
};
use parking_lot::Mutex;
use smallvec::SmallVec;
use std::{marker::PhantomData, sync::Arc};
use util::ResultExt;
impl<V: 'static> Component<V> for SharedString {
fn render(self) -> AnyElement<V> {
Text {
text: self,
state_type: PhantomData,
}
.render()
}
}
impl<V: 'static> Component<V> for &'static str {
fn render(self) -> AnyElement<V> {
Text {
text: self.into(),
state_type: PhantomData,
}
.render()
}
}
// TODO: Figure out how to pass `String` to `child` without this.
// This impl doesn't exist in the `gpui2` crate.
impl<V: 'static> Component<V> for String {
fn render(self) -> AnyElement<V> {
Text {
text: self.into(),
state_type: PhantomData,
}
.render()
}
}
pub struct Text<V> {
text: SharedString,
state_type: PhantomData<V>,
}
unsafe impl<V> Send for Text<V> {}
unsafe impl<V> Sync for Text<V> {}
impl<V: 'static> Component<V> for Text<V> {
fn render(self) -> AnyElement<V> {
AnyElement::new(self)
}
}
impl<V: 'static> Element<V> for Text<V> {
type ElementState = Arc<Mutex<Option<TextElementState>>>;
fn id(&self) -> Option<crate::ElementId> {
None
}
fn initialize(
&mut self,
_view_state: &mut V,
element_state: Option<Self::ElementState>,
_cx: &mut ViewContext<V>,
) -> Self::ElementState {
element_state.unwrap_or_default()
}
fn layout(
&mut self,
_view: &mut V,
element_state: &mut Self::ElementState,
cx: &mut ViewContext<V>,
) -> LayoutId {
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 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 line_count = lines
.iter()
.map(|line| line.wrap_count() + 1)
.sum::<usize>();
let size = Size {
width: lines.iter().map(|line| line.layout.width).max().unwrap(),
height: line_height * line_count,
};
element_state
.lock()
.replace(TextElementState { lines, line_height });
size
}
});
layout_id
}
fn paint(
&mut self,
bounds: Bounds<Pixels>,
_: &mut V,
element_state: &mut Self::ElementState,
cx: &mut ViewContext<V>,
) {
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,
}