diff --git a/src/widgets/canvas/line.rs b/src/widgets/canvas/line.rs
index cec9f4e7..6e996373 100644
--- a/src/widgets/canvas/line.rs
+++ b/src/widgets/canvas/line.rs
@@ -66,7 +66,7 @@ impl<'a> Shape<'a> for Line {
         self.color
     }
 
-    fn points(&'a self) -> Box<Iterator<Item = (f64, f64)> + 'a> {
+    fn points(&'a self) -> Box<dyn Iterator<Item = (f64, f64)> + 'a> {
         Box::new(self.into_iter())
     }
 }
diff --git a/src/widgets/canvas/map.rs b/src/widgets/canvas/map.rs
index c80b2ab0..cc16840a 100644
--- a/src/widgets/canvas/map.rs
+++ b/src/widgets/canvas/map.rs
@@ -37,7 +37,7 @@ impl<'a> Shape<'a> for Map {
     fn color(&self) -> Color {
         self.color
     }
-    fn points(&'a self) -> Box<Iterator<Item = (f64, f64)> + 'a> {
+    fn points(&'a self) -> Box<dyn Iterator<Item = (f64, f64)> + 'a> {
         Box::new(self.into_iter())
     }
 }
diff --git a/src/widgets/canvas/mod.rs b/src/widgets/canvas/mod.rs
index b2a215bd..3688ede1 100644
--- a/src/widgets/canvas/mod.rs
+++ b/src/widgets/canvas/mod.rs
@@ -28,7 +28,7 @@ pub trait Shape<'a> {
     /// Returns the color of the shape
     fn color(&self) -> Color;
     /// Returns an iterator over all points of the shape
-    fn points(&'a self) -> Box<Iterator<Item = (f64, f64)> + 'a>;
+    fn points(&'a self) -> Box<dyn Iterator<Item = (f64, f64)> + 'a>;
 }
 
 /// Label to draw some text on the canvas
diff --git a/src/widgets/canvas/points.rs b/src/widgets/canvas/points.rs
index be17008c..2453e484 100644
--- a/src/widgets/canvas/points.rs
+++ b/src/widgets/canvas/points.rs
@@ -13,7 +13,7 @@ impl<'a> Shape<'a> for Points<'a> {
     fn color(&self) -> Color {
         self.color
     }
-    fn points(&'a self) -> Box<Iterator<Item = (f64, f64)> + 'a> {
+    fn points(&'a self) -> Box<dyn Iterator<Item = (f64, f64)> + 'a> {
         Box::new(self.into_iter())
     }
 }
diff --git a/src/widgets/canvas/rectangle.rs b/src/widgets/canvas/rectangle.rs
index 91a2e2ba..9408ee4d 100644
--- a/src/widgets/canvas/rectangle.rs
+++ b/src/widgets/canvas/rectangle.rs
@@ -14,7 +14,7 @@ impl<'a> Shape<'a> for Rectangle {
         self.color
     }
 
-    fn points(&'a self) -> Box<Iterator<Item = (f64, f64)> + 'a> {
+    fn points(&'a self) -> Box<dyn Iterator<Item = (f64, f64)> + 'a> {
         let left_line = Line {
             x1: f64::from(self.rect.x),
             y1: f64::from(self.rect.y),
diff --git a/src/widgets/reflow.rs b/src/widgets/reflow.rs
index 32e951a3..4d39a113 100644
--- a/src/widgets/reflow.rs
+++ b/src/widgets/reflow.rs
@@ -15,7 +15,7 @@ pub trait LineComposer<'a> {
 
 /// A state machine that wraps lines on word boundaries.
 pub struct WordWrapper<'a, 'b> {
-    symbols: &'b mut Iterator<Item = Styled<'a>>,
+    symbols: &'b mut dyn Iterator<Item = Styled<'a>>,
     max_line_width: u16,
     current_line: Vec<Styled<'a>>,
     next_line: Vec<Styled<'a>>,
@@ -23,7 +23,7 @@ pub struct WordWrapper<'a, 'b> {
 
 impl<'a, 'b> WordWrapper<'a, 'b> {
     pub fn new(
-        symbols: &'b mut Iterator<Item = Styled<'a>>,
+        symbols: &'b mut dyn Iterator<Item = Styled<'a>>,
         max_line_width: u16,
     ) -> WordWrapper<'a, 'b> {
         WordWrapper {
@@ -121,14 +121,14 @@ impl<'a, 'b> LineComposer<'a> for WordWrapper<'a, 'b> {
 
 /// A state machine that truncates overhanging lines.
 pub struct LineTruncator<'a, 'b> {
-    symbols: &'b mut Iterator<Item = Styled<'a>>,
+    symbols: &'b mut dyn Iterator<Item = Styled<'a>>,
     max_line_width: u16,
     current_line: Vec<Styled<'a>>,
 }
 
 impl<'a, 'b> LineTruncator<'a, 'b> {
     pub fn new(
-        symbols: &'b mut Iterator<Item = Styled<'a>>,
+        symbols: &'b mut dyn Iterator<Item = Styled<'a>>,
         max_line_width: u16,
     ) -> LineTruncator<'a, 'b> {
         LineTruncator {