TextArea: cache layout computations

This commit is contained in:
Alexandre Bury 2016-08-02 21:48:12 -07:00
parent e4bc129f4b
commit 5d124e452e

View File

@ -4,7 +4,7 @@ use odds::vec::VecExt;
use std::rc::Rc;
use {Printer, XY};
use {Printer, With, XY};
use direction::Direction;
use vec::Vec2;
use event::{Event, EventResult, Key};
@ -63,6 +63,25 @@ impl TextArea {
&self.content
}
fn invalidate(&mut self) {
self.last_size = None;
}
/// Sets the content of the view.
pub fn set_content<S: Into<String>>(&mut self, content: S) {
self.content = content.into();
if let Some(size) = self.last_size.map(|s| s.map(|s| s.value)) {
self.compute_rows(size);
}
}
/// Sets the content of the view.
///
/// Chainable variant.
pub fn content<S: Into<String>>(self, content: S) -> Self {
self.with(|s| s.set_content(content))
}
/// Finds the row containing the grapheme at the given offset
fn row_at(&self, offset: usize) -> usize {
// println_stderr!("Offset: {}", offset);
@ -161,7 +180,10 @@ impl TextArea {
}
fn is_cache_valid(&self, size: Vec2) -> bool {
false
match self.last_size {
None => false,
Some(ref last) => last.x.accept(size.x) && last.y.accept(size.y),
}
}
fn fix_ghost_row(&mut self) {
@ -177,6 +199,11 @@ impl TextArea {
}
fn compute_rows(&mut self, size: Vec2) {
if self.is_cache_valid(size) {
return;
}
// println_stderr!("Computing! Oh yeah!");
let mut available = size.x;
self.rows = make_rows(&self.content, available);
self.fix_ghost_row();
@ -252,6 +279,12 @@ impl TextArea {
///
/// The only damages are assumed to have occured around the cursor.
fn fix_damages(&mut self, delete: bool) {
if self.last_size.is_none() {
// If we don't know our size, it means we'll get a layout command soon.
// So no need to do that here.
return;
}
let size = self.last_size.unwrap().map(|s| s.value);
// Find affected text.
@ -295,6 +328,7 @@ impl TextArea {
// This changes everything.
// TODO: compute_rows() currently makes a scroll-less attempt.
// Here, we know it's just no gonna happen.
self.invalidate();
self.compute_rows(size);
return;
}
@ -399,7 +433,7 @@ impl View for TextArea {
}
fn layout(&mut self, size: Vec2) {
self.last_size = Some(SizeCache::build(size, size));
self.compute_rows(size);
self.scrollbase.set_heights(size.y, self.rows.len());
}
}