From 6fa5b18cc60f9be75727c560063bfe591bf99f3d Mon Sep 17 00:00:00 2001
From: Alexandre Bury <alexandre.bury@gmail.com>
Date: Sat, 23 Sep 2017 13:31:17 -0700
Subject: [PATCH] Add Canvas::wrap(View)

Behaves like a dynamic ViewWrapper
---
 src/views/canvas.rs | 55 ++++++++++++++++++++++++++++-----------------
 1 file changed, 35 insertions(+), 20 deletions(-)

diff --git a/src/views/canvas.rs b/src/views/canvas.rs
index fab5346..c500e5a 100644
--- a/src/views/canvas.rs
+++ b/src/views/canvas.rs
@@ -11,14 +11,29 @@ use view::View;
 pub struct Canvas<T> {
     state: T,
 
-    draw: Box<Fn(&Printer, &T)>,
-    on_event: Box<FnMut(Event, &mut T) -> EventResult>,
-    required_size: Box<FnMut(Vec2, &mut T) -> Vec2>,
-    layout: Box<FnMut(Vec2, &mut T)>,
-    take_focus: Box<FnMut(Direction, &mut T) -> bool>,
+    draw: Box<Fn(&T, &Printer)>,
+    on_event: Box<FnMut(&mut T, Event) -> EventResult>,
+    required_size: Box<FnMut(&mut T, Vec2) -> Vec2>,
+    layout: Box<FnMut(&mut T, Vec2)>,
+    take_focus: Box<FnMut(&mut T, Direction) -> bool>,
     needs_relayout: Box<Fn(&T) -> bool>,
 }
 
+impl <T: 'static + View> Canvas<T> {
+    /// Creates a new Canvas around the given view.
+    ///
+    /// By default, forwards all calls to the inner view.
+    pub fn wrap(view: T) -> Self {
+        Canvas::new(view)
+            .with_draw(T::draw)
+            .with_on_event(T::on_event)
+            .with_required_size(T::required_size)
+            .with_layout(T::layout)
+            .with_take_focus(T::take_focus)
+            .with_needs_relayout(T::needs_relayout)
+    }
+}
+
 impl<T> Canvas<T> {
     /// Creates a new, empty Canvas.
     ///
@@ -50,7 +65,7 @@ impl<T> Canvas<T> {
 
     /// Sets the closure for `draw(&Printer)`.
     pub fn set_draw<F>(&mut self, f: F)
-        where F: 'static + Fn(&Printer, &T)
+        where F: 'static + Fn(&T, &Printer)
     {
         self.draw = Box::new(f);
     }
@@ -59,14 +74,14 @@ impl<T> Canvas<T> {
     ///
     /// Chainable variant.
     pub fn with_draw<F>(self, f: F) -> Self
-        where F: 'static + Fn(&Printer, &T)
+        where F: 'static + Fn(&T, &Printer)
     {
         self.with(|s| s.set_draw(f))
     }
 
     /// Sets the closure for `on_event(Event)`.
     pub fn set_on_event<F>(&mut self, f: F)
-        where F: 'static + FnMut(Event, &mut T) -> EventResult
+        where F: 'static + FnMut(&mut T, Event) -> EventResult
     {
         self.on_event = Box::new(f);
     }
@@ -75,14 +90,14 @@ impl<T> Canvas<T> {
     ///
     /// Chainable variant.
     pub fn with_on_event<F>(self, f: F) -> Self
-        where F: 'static + FnMut(Event, &mut T) -> EventResult
+        where F: 'static + FnMut(&mut T, Event) -> EventResult
     {
         self.with(|s| s.set_on_event(f))
     }
 
     /// Sets the closure for `required_size(Vec2)`.
     pub fn set_required_size<F>(&mut self, f: F)
-        where F: 'static + FnMut(Vec2, &mut T) -> Vec2
+        where F: 'static + FnMut(&mut T, Vec2) -> Vec2
     {
         self.required_size = Box::new(f);
     }
@@ -91,14 +106,14 @@ impl<T> Canvas<T> {
     ///
     /// Chainable variant.
     pub fn with_required_size<F>(self, f: F) -> Self
-        where F: 'static + FnMut(Vec2, &mut T) -> Vec2
+        where F: 'static + FnMut(&mut T, Vec2) -> Vec2
     {
         self.with(|s| s.set_required_size(f))
     }
 
     /// Sets the closure for `layout(Vec2)`.
     pub fn set_layout<F>(&mut self, f: F)
-        where F: 'static + FnMut(Vec2, &mut T)
+        where F: 'static + FnMut(&mut T, Vec2)
     {
         self.layout = Box::new(f);
     }
@@ -107,14 +122,14 @@ impl<T> Canvas<T> {
     ///
     /// Chainable variant.
     pub fn with_layout<F>(self, f: F) -> Self
-        where F: 'static + FnMut(Vec2, &mut T)
+        where F: 'static + FnMut(&mut T, Vec2)
     {
         self.with(|s| s.set_layout(f))
     }
 
     /// Sets the closure for `take_focus(Direction)`.
     pub fn set_take_focus<F>(&mut self, f: F)
-        where F: 'static + FnMut(Direction, &mut T) -> bool
+        where F: 'static + FnMut(&mut T, Direction) -> bool
     {
         self.take_focus = Box::new(f);
     }
@@ -123,7 +138,7 @@ impl<T> Canvas<T> {
     ///
     /// Chainable variant.
     pub fn with_take_focus<F>(self, f: F) -> Self
-        where F: 'static + FnMut(Direction, &mut T) -> bool
+        where F: 'static + FnMut(&mut T, Direction) -> bool
     {
         self.with(|s| s.set_take_focus(f))
     }
@@ -148,22 +163,22 @@ impl<T> Canvas<T> {
 
 impl<T> View for Canvas<T> {
     fn draw(&self, printer: &Printer) {
-        (self.draw)(printer, &self.state);
+        (self.draw)(&self.state, printer);
     }
 
     fn on_event(&mut self, event: Event) -> EventResult {
-        (self.on_event)(event, &mut self.state)
+        (self.on_event)(&mut self.state, event)
     }
 
     fn required_size(&mut self, constraint: Vec2) -> Vec2 {
-        (self.required_size)(constraint, &mut self.state)
+        (self.required_size)(&mut self.state, constraint)
     }
 
     fn layout(&mut self, size: Vec2) {
-        (self.layout)(size, &mut self.state);
+        (self.layout)(&mut self.state, size);
     }
 
     fn take_focus(&mut self, source: Direction) -> bool {
-        (self.take_focus)(source, &mut self.state)
+        (self.take_focus)(&mut self.state, source)
     }
 }