Add `step` member to slider widgets

Both the native and the web slider now have a member `step` to control
the least possible change of the slider's value. It defaults to 1.0
for all sliders and can be adjusted with the step method.

3 files changed, 51 insertions, 27 deletions

diff --git a/examples/color_palette/src/main.rs b/examples/color_palette/src/main.rs
index cec6ac79..9f39fe56 100644
--- a/examples/color_palette/src/main.rs
+++ b/examples/color_palette/src/main.rs
@@ -288,9 +288,15 @@ impl<C: 'static + ColorSpace + Copy> ColorPicker<C> {
             .spacing(10)
             .align_items(Align::Center)
             .push(Text::new(C::LABEL).width(Length::Units(50)))
-            .push(Slider::new(s1, cr1, c1, move |v| C::new(v, c2, c3)))
-            .push(Slider::new(s2, cr2, c2, move |v| C::new(c1, v, c3)))
-            .push(Slider::new(s3, cr3, c3, move |v| C::new(c1, c2, v)))
+            .push(
+                Slider::new(s1, cr1, c1, move |v| C::new(v, c2, c3)).step(0.01),
+            )
+            .push(
+                Slider::new(s2, cr2, c2, move |v| C::new(c1, v, c3)).step(0.01),
+            )
+            .push(
+                Slider::new(s3, cr3, c3, move |v| C::new(c1, c2, v)).step(0.01),
+            )
             .push(
                 Text::new(color.to_string())
                     .width(Length::Units(185))
diff --git a/examples/integration/src/controls.rs b/examples/integration/src/controls.rs
index e6e74995..824f9f53 100644
--- a/examples/integration/src/controls.rs
+++ b/examples/integration/src/controls.rs
@@ -48,24 +48,33 @@ impl Program for Controls {
         let sliders = Row::new()
             .width(Length::Units(500))
             .spacing(20)
-            .push(Slider::new(r, 0.0..=1.0, background_color.r, move |r| {
-                Message::BackgroundColorChanged(Color {
-                    r,
-                    ..background_color
+            .push(
+                Slider::new(r, 0.0..=1.0, background_color.r, move |r| {
+                    Message::BackgroundColorChanged(Color {
+                        r,
+                        ..background_color
+                    })
                 })
-            }))
-            .push(Slider::new(g, 0.0..=1.0, background_color.g, move |g| {
-                Message::BackgroundColorChanged(Color {
-                    g,
-                    ..background_color
+                .step(0.01),
+            )
+            .push(
+                Slider::new(g, 0.0..=1.0, background_color.g, move |g| {
+                    Message::BackgroundColorChanged(Color {
+                        g,
+                        ..background_color
+                    })
                 })
-            }))
-            .push(Slider::new(b, 0.0..=1.0, background_color.b, move |b| {
-                Message::BackgroundColorChanged(Color {
-                    b,
-                    ..background_color
+                .step(0.01),
+            )
+            .push(
+                Slider::new(b, 0.0..=1.0, background_color.b, move |b| {
+                    Message::BackgroundColorChanged(Color {
+                        b,
+                        ..background_color
+                    })
                 })
-            }));
+                .step(0.01),
+            );
 
         Row::new()
             .width(Length::Fill)
diff --git a/examples/tour/src/main.rs b/examples/tour/src/main.rs
index c9678b9d..43627cc3 100644
--- a/examples/tour/src/main.rs
+++ b/examples/tour/src/main.rs
@@ -500,15 +500,24 @@ impl<'a> Step {
             .push(
                 Row::new()
                     .spacing(10)
-                    .push(Slider::new(red, 0.0..=1.0, color.r, move |r| {
-                        StepMessage::TextColorChanged(Color { r, ..color })
-                    }))
-                    .push(Slider::new(green, 0.0..=1.0, color.g, move |g| {
-                        StepMessage::TextColorChanged(Color { g, ..color })
-                    }))
-                    .push(Slider::new(blue, 0.0..=1.0, color.b, move |b| {
-                        StepMessage::TextColorChanged(Color { b, ..color })
-                    })),
+                    .push(
+                        Slider::new(red, 0.0..=1.0, color.r, move |r| {
+                            StepMessage::TextColorChanged(Color { r, ..color })
+                        })
+                        .step(0.01),
+                    )
+                    .push(
+                        Slider::new(green, 0.0..=1.0, color.g, move |g| {
+                            StepMessage::TextColorChanged(Color { g, ..color })
+                        })
+                        .step(0.01),
+                    )
+                    .push(
+                        Slider::new(blue, 0.0..=1.0, color.b, move |b| {
+                            StepMessage::TextColorChanged(Color { b, ..color })
+                        })
+                        .step(0.01),
+                    ),
             );
 
         Self::container("Text")