Scroll behavior component (#1107)

* Naive first step to refactor out scroll logic into separate component

* Move a bunch of event logic to `scroll_component` from `Scroll`

* Add method to coordinate painting with `scroll_component`

* Move a bunch of lifecycle logic to `scroll_component` from `Scroll`

* Documentation pass on `scroll_component`

* Rename `Scroll` to `AbsoluteScroll` & add scroll functionality to `List`

* Add ability to change layout axis for `List` with builder fn

* Scroll behavior component changelog

* Pass `BarHoveredState` by value and add impl Default for ScrollComponent

* `ScrollComponent` review changes

* Add some missing information to `ScrollComponent` documentation

* `ScrollContainer` review take 2

* Changes from #1057

* ScrollComponent clippy

* Remove List changes (updated to master) & fix Scroll regression

* Add missing doc comments

* Be a bit more careful about event consuming

* Fix dup changelog entry & doc comment misspelling

AUTHORS

@@ -11,4 +11,5 @@ Kaiyin Zhong
 Kaur Kuut
 Leopold Luley
 Andrey Kabylin
-Robert Wittams
+Garrett Risley
+Robert Wittams

CHANGELOG.md

@@ -12,6 +12,7 @@ You can find its changes [documented below](#060---2020-06-01).
 - Export `Image` and `ImageData` by default. ([#1011] by [@covercash2])
 - Re-export `druid_shell::Scalable` under `druid` namespace. ([#1075] by [@ForLoveOfCats])
 - `TextBox` now supports ctrl and shift hotkeys. ([#1076] by [@vkahl])
+- `ScrollComponent` for ease of adding consistent, customized, scrolling behavior to a widget. ([#1107] by [@ForLoveOfCats])
 - Selection text color to textbox. ([#1093] by [@sysint64])
 - `BoxConstraints::UNBOUNDED` constant. ([#1126] by [@danieldulaney])
 - Close requests from the shell can now be intercepted ([#1118] by [@jneem])
@@ -396,6 +397,7 @@ Last release without a changelog :(
 [#1093]: https://github.com/linebender/druid/pull/1093
 [#1100]: https://github.com/linebender/druid/pull/1100
 [#1103]: https://github.com/linebender/druid/pull/1103
+[#1107]: https://github.com/linebender/druid/pull/1107
 [#1118]: https://github.com/linebender/druid/pull/1118
 [#1119]: https://github.com/linebender/druid/pull/1119
 [#1120]: https://github.com/linebender/druid/pull/1120

druid/src/lib.rs

@@ -157,6 +157,7 @@ pub mod lens;
 mod localization;
 mod menu;
 mod mouse;
+pub mod scroll_component;
 #[cfg(not(target_arch = "wasm32"))]
 #[cfg(test)]
 mod tests;