Merge branch 'virtual-scroll-list-example'

CHANGELOG.md

@@ -249,6 +249,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   default is `true`, which was the behavior before this flag was added.
 - `Image` now supports `ImageCornerRadius`. Thanks to @danbulant for helping
   with this change!
+- `Scroll` now exposes its scroll amount, maximum scroll, and more information
+  that allows completely customizing a scroll view's behavior. Thanks to
+  @danbulant for helping with this change!
 
 
 [139]: https://github.com/khonsulabs/cushy/issues/139

examples/virtual-scroll-list.rs

@@ -0,0 +1,65 @@
+use cushy::styles::{Dimension, DimensionRange, Edges};
+use cushy::value::{Destination, Dynamic, Source};
+use cushy::widget::MakeWidget;
+use cushy::Run;
+use figures::units::{Lp, UPx};
+use figures::{Point, Size};
+
+fn list() -> impl MakeWidget {
+    let height = Lp::inches(10);
+    let content_size: Dynamic<Size<UPx>> = Dynamic::default();
+    let control_size = Dynamic::default();
+    let current_scroll: Dynamic<Point<UPx>> = Dynamic::default();
+    let max_scroll = Dynamic::default();
+
+    let content = content_size.map_each(|s| format!("Content size: {:?};", s));
+    let control = control_size.map_each(|s| format!("Control size: {:?};", s));
+    let scroll = current_scroll.map_each(|s| format!("Current scroll: {:?};", s));
+    let max = max_scroll.map_each(|s| format!("Max scroll: {:?};", s));
+
+    let content = content
+        .and(control)
+        .and(scroll)
+        .and(max)
+        .into_columns()
+        .and("Hello world!")
+        .into_rows()
+        .pad_by(current_scroll.map_each(|scroll| Edges {
+            top: Dimension::from(scroll.y),
+            ..Default::default()
+        }))
+        .size(Size::new(
+            DimensionRange::default(),
+            DimensionRange::from(height),
+        ));
+
+    let scroll = content.scroll();
+
+    scroll
+        .content_size()
+        .for_each_cloned(move |s| content_size.set(s))
+        .persist();
+    scroll
+        .control_size()
+        .for_each_cloned(move |s| control_size.set(s))
+        .persist();
+    scroll
+        .scroll
+        .for_each_cloned(move |s| current_scroll.set(s))
+        .persist();
+    scroll
+        .max_scroll()
+        .for_each_cloned(move |s| max_scroll.set(s))
+        .persist();
+
+    scroll.expand()
+}
+
+fn main() -> cushy::Result {
+    list().run()
+}
+
+#[test]
+fn runs() {
+    cushy::example!(list).untested_still_frame();
+}

guide/src/about/reactive.md

@@ -63,7 +63,8 @@ change. Let's revisit the example from the [intro](../intro.md):
 Both the [`Input`][input] and the [`Label`][label] widgets have been given
 instances of `Dynamic<String>`s, but they are two different dynamics. The text
 input field was given the dynamic we want to be edited. We react to the changes
-through the `name.map_each(...)` callback.
+through the `name.map_each(...)` callback. You can react to multiple `Dynamic`s
+at once using `(&name, &surname).map_each(...)` callback.
 
 ## What is a `DynamicReader<T>`?
 

src/styles.rs

@@ -757,6 +757,12 @@ impl Default for Dimension {
     }
 }
 
+impl From<UPx> for Dimension {
+    fn from(value: UPx) -> Self {
+        Self::Px(value.into_signed())
+    }
+}
+
 impl From<Px> for Dimension {
     fn from(value: Px) -> Self {
         Self::Px(value)
@@ -1212,7 +1218,7 @@ impl NamedComponent for Cow<'_, ComponentName> {
 }
 
 /// A type describing characteristics about the edges of a rectangle.
-#[derive(Clone, Copy, Debug)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub struct Edges<T = FlexibleDimension> {
     /// The left edge
     pub left: T,