feat(settings): settings item builder API

src/widget/settings/item.rs

@@ -4,9 +4,10 @@
 use std::borrow::Cow;
 
 use crate::{widget::text, Element, Renderer};
-use iced::widget::{horizontal_space, row, Row};
+use derive_setters::Setters;
+use iced::widget::{column, horizontal_space, row, Row};
 
-/// A setting within a settings view section.
+/// A settings item aligned in a row
 #[must_use]
 #[allow(clippy::module_name_repetitions)]
 pub fn item<'a, Message: 'static>(
@@ -29,3 +30,60 @@ pub fn item_row<Message>(children: Vec<Element<Message>>) -> Row<Message, Render
         .padding([0, 18])
         .spacing(12)
 }
+
+/// Creates a builder for an item, beginning with the title.
+pub fn builder<'a, Message: 'static>(title: impl Into<Cow<'a, str>>) -> Item<'a, Message> {
+    Item {
+        title: title.into(),
+        description: None,
+        icon: None,
+    }
+}
+
+/// A builder for a settings item.
+#[derive(Setters)]
+pub struct Item<'a, Message> {
+    /// Describes the item being controlled.
+    title: Cow<'a, str>,
+
+    /// A description to display beneath the title.
+    #[setters(strip_option, into)]
+    description: Option<Cow<'a, str>>,
+
+    /// A custom icon to display before the text.
+    #[setters(strip_option, into)]
+    icon: Option<Element<'a, Message>>,
+}
+
+impl<'a, Message: 'static> Item<'a, Message> {
+    /// Assigns a control to the item.
+    pub fn control(self, widget: impl Into<Element<'a, Message>>) -> Row<'a, Message, Renderer> {
+        let mut contents = Vec::with_capacity(4);
+
+        if let Some(icon) = self.icon {
+            contents.push(icon);
+        }
+
+        if let Some(description) = self.description {
+            let title = text(self.title).size(18);
+            let desc = text(description).size(12);
+
+            contents.push(column!(title, desc).spacing(2).into());
+        } else {
+            contents.push(text(self.title).into());
+        }
+
+        contents.push(horizontal_space(iced::Length::Fill).into());
+        contents.push(widget.into());
+
+        item_row(contents)
+    }
+
+    pub fn toggler(
+        self,
+        is_checked: bool,
+        message: impl Fn(bool) -> Message + 'static,
+    ) -> Row<'a, Message, Renderer> {
+        self.control(crate::widget::toggler(None, is_checked, message))
+    }
+}

src/widget/settings/mod.rs

@@ -1,7 +1,7 @@
 // Copyright 2022 System76 <info@system76.com>
 // SPDX-License-Identifier: MPL-2.0
 
-mod item;
+pub mod item;
 mod section;
 
 pub use self::item::{item, item_row};