auto-shrink ScrollArea to content size

Unless the user disables it with `ScollArea::auto_shrink([false; 2])`.
This commit is contained in:
Emil Ernerfeldt 2021-10-06 23:48:09 +02:00
parent a1bf5aff47
commit ce8d863249
3 changed files with 60 additions and 50 deletions

View file

@ -25,6 +25,7 @@ NOTE: [`eframe`](eframe/CHANGELOG.md), [`egui_web`](egui_web/CHANGELOG.md), [`eg
* MSRV (Minimum Supported Rust Version) is now `1.54.0`.
* By default, `DragValue`:s no longer show a tooltip when hovered. Change with `Style::explanation_tooltips`.
* Smaller and nicer color picker.
* `ScrollArea` will auto-shrink to content size unless told otherwise using `ScollArea::auto_shrink`.
### Fixed 🐛
* Fix wrongly sized multiline `TextEdit` in justified layouts.

View file

@ -341,14 +341,14 @@ impl ScrollArea {
let y_min = ui.max_rect().top() + min_row as f32 * row_height_with_spacing;
let y_max = ui.max_rect().top() + max_row as f32 * row_height_with_spacing;
let mut viewport_ui = ui.child_ui(
Rect::from_x_y_ranges(ui.max_rect().x_range(), y_min..=y_max),
*ui.layout(),
);
viewport_ui.skip_ahead_auto_ids(min_row); // Make sure we get consistent IDs.
let rect = Rect::from_x_y_ranges(ui.max_rect().x_range(), y_min..=y_max);
add_contents(&mut viewport_ui, min_row..max_row)
ui.allocate_ui_at_rect(rect, |viewport_ui| {
viewport_ui.skip_ahead_auto_ids(min_row); // Make sure we get consistent IDs.
add_contents(viewport_ui, min_row..max_row)
})
.inner
})
}
@ -389,10 +389,9 @@ impl Prepared {
let content_size = content_ui.min_size();
// We take the scroll target so only this ScrollArea will use it.
for d in 0..2 {
if has_bar[d] {
// We take the scroll target so only this ScrollArea will use it:
let scroll_target = content_ui.ctx().frame_state().scroll_target[d].take();
if let Some((scroll, align)) = scroll_target {
let center_factor = align.to_factor();
@ -412,19 +411,15 @@ impl Prepared {
}
let inner_rect = {
// At this point this is the available size for the inner rect.
let mut inner_size = inner_rect.size();
for d in 0..2 {
inner_size[d] = if has_bar[d] {
if auto_shrink[d] {
inner_size[d].min(content_size[d]) // shrink scroll area if content is small
} else {
inner_size[d] // let scroll area be larger than content; fill with blank space
}
} else if inner_size[d].is_finite() {
inner_size[d].max(content_size[d]) // Expand to fit content
} else {
content_size[d] // ScrollArea is in an infinitely sized parent; take size of parent
inner_size[d] = match (has_bar[d], auto_shrink[d]) {
(true, true) => inner_size[d].min(content_size[d]), // shrink scroll area if content is small
(true, false) => inner_size[d], // let scroll area be larger than content; fill with blank space
(false, true) => content_size[d], // Follow the content (expand/contract to fit it).
(false, false) => inner_size[d].max(content_size[d]), // Expand to fit content
};
}

View file

@ -32,7 +32,7 @@ impl super::Demo for Scrolling {
.open(open)
.resizable(false)
.show(ctx, |ui| {
use super::View;
use super::View as _;
self.ui(ui);
});
}
@ -77,12 +77,17 @@ fn huge_content_lines(ui: &mut egui::Ui) {
let text_style = TextStyle::Body;
let row_height = ui.fonts()[text_style].row_height();
let num_rows = 10_000;
ScrollArea::vertical().show_rows(ui, row_height, num_rows, |ui, row_range| {
for row in row_range {
let text = format!("This is row {}/{}", row + 1, num_rows);
ui.label(text);
}
});
ScrollArea::vertical().auto_shrink([false; 2]).show_rows(
ui,
row_height,
num_rows,
|ui, row_range| {
for row in row_range {
let text = format!("This is row {}/{}", row + 1, num_rows);
ui.label(text);
}
},
);
}
fn huge_content_painter(ui: &mut egui::Ui) {
@ -94,32 +99,39 @@ fn huge_content_painter(ui: &mut egui::Ui) {
let row_height = ui.fonts()[text_style].row_height() + ui.spacing().item_spacing.y;
let num_rows = 10_000;
ScrollArea::vertical().show_viewport(ui, |ui, viewport| {
ui.set_height(row_height * num_rows as f32);
ScrollArea::vertical()
.auto_shrink([false; 2])
.show_viewport(ui, |ui, viewport| {
ui.set_height(row_height * num_rows as f32);
let first_item = (viewport.min.y / row_height).floor().at_least(0.0) as usize;
let last_item = (viewport.max.y / row_height).ceil() as usize + 1;
let last_item = last_item.at_most(num_rows);
let first_item = (viewport.min.y / row_height).floor().at_least(0.0) as usize;
let last_item = (viewport.max.y / row_height).ceil() as usize + 1;
let last_item = last_item.at_most(num_rows);
for i in first_item..last_item {
let indentation = (i % 100) as f32;
let x = ui.min_rect().left() + indentation;
let y = ui.min_rect().top() + i as f32 * row_height;
let text = format!(
"This is row {}/{}, indented by {} pixels",
i + 1,
num_rows,
indentation
);
ui.painter().text(
pos2(x, y),
Align2::LEFT_TOP,
text,
text_style,
ui.visuals().text_color(),
);
}
});
let mut used_rect = Rect::NOTHING;
for i in first_item..last_item {
let indentation = (i % 100) as f32;
let x = ui.min_rect().left() + indentation;
let y = ui.min_rect().top() + i as f32 * row_height;
let text = format!(
"This is row {}/{}, indented by {} pixels",
i + 1,
num_rows,
indentation
);
let text_rect = ui.painter().text(
pos2(x, y),
Align2::LEFT_TOP,
text,
text_style,
ui.visuals().text_color(),
);
used_rect = used_rect.union(text_rect);
}
ui.allocate_rect(used_rect, Sense::hover()); // make sure it is visible!
});
}
// ----------------------------------------------------------------------------
@ -184,7 +196,9 @@ impl super::View for ScrollTo {
scroll_bottom |= ui.button("Scroll to bottom").clicked();
});
let mut scroll_area = ScrollArea::vertical().max_height(200.0);
let mut scroll_area = ScrollArea::vertical()
.max_height(200.0)
.auto_shrink([false; 2]);
if go_to_scroll_offset {
scroll_area = scroll_area.scroll_offset(self.offset);
}