Add RefCellView

Wraps a view and provide interior mutability

Cargo.toml

@@ -1,11 +1,11 @@
 [package]
 authors = ["Alexandre Bury <alexandre.bury@gmail.com>"]
 build = "build.rs"
+categories = ["command-line-interface", "gui"]
 description = "A TUI (Text User Interface) library focused on ease-of-use."
 documentation = "https://gyscos.github.io/Cursive/cursive/index.html"
 exclude = ["doc", "assets"]
 keywords = ["ncurses", "TUI", "UI"]
-categories = ["command-line-interface", "gui"]
 license = "MIT"
 name = "cursive"
 readme = "Readme.md"
@@ -13,7 +13,11 @@ repository = "https://github.com/gyscos/Cursive"
 version = "0.4.0"
 
 [badges]
-travis-ci = { repository = "gyscos/Cursive" }
+
+[badges.travis-ci]
+repository = "gyscos/Cursive"
+
+[build-dependencies]
 
 [build-dependencies.skeptic]
 optional = true
@@ -23,18 +27,19 @@ version = "0.6"
 chan = "0.1.18"
 num = "0.1"
 odds = "0.2"
+owning_ref = "0.2.4"
 toml = "0.2"
 unicode-segmentation = "1.0"
 unicode-width = "0.1"
 
-[dependencies.chan-signal]
-optional = true
-version = "0.1"
-
 [dependencies.bear-lib-terminal]
 optional = true
 version = "1.3.1"
 
+[dependencies.chan-signal]
+optional = true
+version = "0.1"
+
 [dependencies.ncurses]
 features = ["wide"]
 optional = true
@@ -55,8 +60,8 @@ skeptic = "0.6"
 
 [features]
 default = ["ncurses"]
-termion-backend = ["termion", "chan-signal"]
 pancurses-backend = ["pancurses"]
+termion-backend = ["termion", "chan-signal"]
 
 [lib]
 name = "cursive"

src/lib.rs

@@ -64,6 +64,7 @@ extern crate unicode_segmentation;
 extern crate unicode_width;
 extern crate odds;
 extern crate num;
+extern crate owning_ref;
 
 #[macro_use]
 extern crate chan;

src/views/mod.rs

@@ -52,6 +52,7 @@ mod menu_popup;
 mod panel;
 mod progress_bar;
 mod radio;
+mod refcell_view;
 mod select_view;
 mod slider_view;
 mod shadow_view;
@@ -78,6 +79,7 @@ pub use self::menubar::Menubar;
 pub use self::panel::Panel;
 pub use self::progress_bar::{Counter, ProgressBar};
 pub use self::radio::{RadioGroup, RadioButton};
+pub use self::refcell_view::{RefCellView, ViewRef};
 pub use self::select_view::SelectView;
 pub use self::shadow_view::ShadowView;
 pub use self::sized_view::SizedView;

src/views/refcell_view.rs

@@ -0,0 +1,49 @@
+
+
+use owning_ref::{RcRef, OwningHandle};
+
+use std::cell::{RefCell, RefMut};
+use std::rc::Rc;
+use view::{View, ViewWrapper};
+
+/// Wrapper around a view to provide interior mutability.
+pub struct RefCellView<V: View> {
+    view: Rc<RefCell<V>>,
+}
+
+/// Mutable reference to a view.
+pub type ViewRef<V> = OwningHandle<RcRef<RefCell<V>>, RefMut<'static, V>>;
+
+impl<V: View> RefCellView<V> {
+    /// Wraps `view` in a new `RefCellView`.
+    pub fn new(view: V) -> Self {
+        RefCellView { view: Rc::new(RefCell::new(view)) }
+    }
+
+    /// Gets mutable access to the inner view.
+    pub fn get_mut(&mut self) -> ViewRef<V> {
+        // TODO: return a standalone item (not tied to our lifetime)
+        // that bundles `self.view.clone()` and allow mutable reference to
+        // the inner view.
+        let cell_ref = RcRef::new(self.view.clone());
+
+        OwningHandle::new(cell_ref,
+                          |x| unsafe { x.as_ref() }.unwrap().borrow_mut())
+    }
+}
+
+impl<T: View> ViewWrapper for RefCellView<T> {
+    type V = T;
+
+    fn with_view<F, R>(&self, f: F) -> R
+        where F: FnOnce(&Self::V) -> R
+    {
+        f(&*self.view.borrow())
+    }
+
+    fn with_view_mut<F, R>(&mut self, f: F) -> R
+        where F: FnOnce(&mut Self::V) -> R
+    {
+        f(&mut *self.view.borrow_mut())
+    }
+}