feat!(app): ContextDrawer return type for context_drawer method

src/app/context_drawer.rs

@@ -0,0 +1,62 @@
+use std::borrow::Cow;
+
+use crate::Element;
+
+pub struct ContextDrawer<'a, Message: Clone + 'static> {
+    pub title: Option<Cow<'a, str>>,
+    pub header_actions: Vec<Element<'a, Message>>,
+    pub header: Option<Element<'a, Message>>,
+    pub content: Element<'a, Message>,
+    pub footer: Option<Element<'a, Message>>,
+    pub on_close: Message,
+}
+
+#[cfg(feature = "about")]
+pub fn about<'a, Message: Clone + 'static>(
+    about: &'a crate::widget::about::About,
+    on_url_press: impl Fn(String) -> Message,
+    on_close: Message,
+) -> ContextDrawer<'a, Message> {
+    context_drawer(crate::widget::about(about, on_url_press), on_close)
+}
+
+pub fn context_drawer<'a, Message: Clone + 'static>(
+    content: impl Into<Element<'a, Message>>,
+    on_close: Message,
+) -> ContextDrawer<'a, Message> {
+    ContextDrawer {
+        title: None,
+        content: content.into(),
+        header_actions: vec![],
+        footer: None,
+        on_close,
+        header: None,
+    }
+}
+
+impl<'a, Message: Clone + 'static> ContextDrawer<'a, Message> {
+    /// Set a context drawer header title
+    pub fn title(mut self, title: impl Into<Cow<'a, str>>) -> Self {
+        self.title = Some(title.into());
+        self
+    }
+    /// App-specific actions at the start of the context drawer header
+    pub fn header_actions(
+        mut self,
+        header_actions: impl IntoIterator<Item = Element<'a, Message>>,
+    ) -> Self {
+        self.header_actions = header_actions.into_iter().collect();
+        self
+    }
+    /// Non-scrolling elements placed below the context drawer title row
+    pub fn header(mut self, header: impl Into<Element<'a, Message>>) -> Self {
+        self.header = Some(header.into());
+        self
+    }
+
+    /// Elements placed below the context drawer scrollable
+    pub fn footer(mut self, footer: impl Into<Element<'a, Message>>) -> Self {
+        self.footer = Some(footer.into());
+        self
+    }
+}