Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Add ComboBox::icon() #1405

Merged
merged 2 commits into from
Mar 23, 2022
Merged
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
60 changes: 57 additions & 3 deletions egui/src/containers/combo_box.rs
Original file line number Diff line number Diff line change
@@ -1,6 +1,9 @@
use crate::{style::WidgetVisuals, *};
use epaint::Shape;

/// A function that paints the `ComboBox` icon
pub type IconPainter = Box<dyn FnOnce(&Ui, Rect, &WidgetVisuals, bool)>;

/// A drop-down selection menu with a descriptive label.
///
/// ```
Expand All @@ -24,6 +27,7 @@ pub struct ComboBox {
label: Option<WidgetText>,
selected_text: WidgetText,
width: Option<f32>,
icon: Option<IconPainter>,
}

impl ComboBox {
Expand All @@ -34,6 +38,7 @@ impl ComboBox {
label: Some(label.into()),
selected_text: Default::default(),
width: None,
icon: None,
}
}

Expand All @@ -45,6 +50,7 @@ impl ComboBox {
label: Some(label),
selected_text: Default::default(),
width: None,
icon: None,
}
}

Expand All @@ -55,6 +61,7 @@ impl ComboBox {
label: Default::default(),
selected_text: Default::default(),
width: None,
icon: None,
}
}

Expand All @@ -70,6 +77,41 @@ impl ComboBox {
self
}

/// Use the provided function to render a different `ComboBox` icon.
/// Defaults to a triangle that expands when the cursor is hovering over the `ComboBox`.
///
/// For example:
/// ```
/// # egui::__run_test_ui(|ui| {
/// # let text = "Selected text";
/// pub fn filled_triangle(
/// ui: &egui::Ui,
/// rect: egui::Rect,
/// visuals: &egui::style::WidgetVisuals,
/// _is_open: bool,
/// ) {
/// let rect = egui::Rect::from_center_size(
/// rect.center(),
/// egui::Vec2::new(rect.width() * 0.6, rect.height() * 0.4),
/// );
/// ui.painter().add(egui::Shape::convex_polygon(
/// vec![rect.left_top(), rect.right_top(), rect.center_bottom()],
/// visuals.fg_stroke.color,
/// visuals.fg_stroke,
/// ));
/// }
///
/// egui::ComboBox::from_id_source("my-combobox")
/// .selected_text(text)
/// .icon(filled_triangle)
/// .show_ui(ui, |_ui| {});
/// # });
/// ```
pub fn icon(mut self, icon_fn: impl FnOnce(&Ui, Rect, &WidgetVisuals, bool) + 'static) -> Self {
self.icon = Some(Box::new(icon_fn));
self
}

/// Show the combo box, with the given ui code for the menu contents.
///
/// Returns `InnerResponse { inner: None }` if the combo box is closed.
Expand All @@ -91,6 +133,7 @@ impl ComboBox {
label,
selected_text,
width,
icon,
} = self;

let button_id = ui.make_persistent_id(id_source);
Expand All @@ -99,7 +142,7 @@ impl ComboBox {
if let Some(width) = width {
ui.spacing_mut().slider_width = width; // yes, this is ugly. Will remove later.
}
let mut ir = combo_box_dyn(ui, button_id, selected_text, menu_contents);
let mut ir = combo_box_dyn(ui, button_id, selected_text, menu_contents, icon);
if let Some(label) = label {
ir.response
.widget_info(|| WidgetInfo::labeled(WidgetType::ComboBox, label.text()));
Expand Down Expand Up @@ -165,6 +208,7 @@ fn combo_box_dyn<'c, R>(
button_id: Id,
selected_text: WidgetText,
menu_contents: Box<dyn FnOnce(&mut Ui) -> R + 'c>,
icon: Option<IconPainter>,
) -> InnerResponse<Option<R>> {
let popup_id = button_id.with("popup");

Expand Down Expand Up @@ -192,7 +236,17 @@ fn combo_box_dyn<'c, R>(
} else {
ui.style().interact(&response)
};
paint_icon(ui.painter(), icon_rect.expand(visuals.expansion), visuals);

if let Some(icon) = icon {
icon(
ui,
icon_rect.expand(visuals.expansion),
visuals,
is_popup_open,
);
} else {
paint_default_icon(ui.painter(), icon_rect.expand(visuals.expansion), visuals);
}

let text_rect = Align2::LEFT_CENTER.align_size_within_rect(galley.size(), rect);
galley.paint_with_visuals(ui.painter(), text_rect.min, visuals);
Expand Down Expand Up @@ -262,7 +316,7 @@ fn button_frame(
response
}

fn paint_icon(painter: &Painter, rect: Rect, visuals: &WidgetVisuals) {
fn paint_default_icon(painter: &Painter, rect: Rect, visuals: &WidgetVisuals) {
let rect = Rect::from_center_size(
rect.center(),
vec2(rect.width() * 0.7, rect.height() * 0.45),
Expand Down