diff options
Diffstat (limited to 'native/src/widget/operation')
-rw-r--r-- | native/src/widget/operation/scrollable.rs | 41 |
1 files changed, 30 insertions, 11 deletions
diff --git a/native/src/widget/operation/scrollable.rs b/native/src/widget/operation/scrollable.rs index 2210137d..3b20631f 100644 --- a/native/src/widget/operation/scrollable.rs +++ b/native/src/widget/operation/scrollable.rs @@ -3,25 +3,19 @@ use crate::widget::{Id, Operation}; /// The internal state of a widget that can be scrolled. pub trait Scrollable { - /// Snaps the scroll of the widget to the given `percentage`. - fn snap_to(&mut self, percentage: f32); + /// Snaps the scroll of the widget to the given `percentage` along the horizontal & vertical axis. + fn snap_to(&mut self, offset: RelativeOffset); } /// Produces an [`Operation`] that snaps the widget with the given [`Id`] to /// the provided `percentage`. -pub fn snap_to<T>(target: Id, percentage: f32) -> impl Operation<T> { +pub fn snap_to<T>(target: Id, offset: RelativeOffset) -> impl Operation<T> { struct SnapTo { target: Id, - percentage: f32, + offset: RelativeOffset, } impl<T> Operation<T> for SnapTo { - fn scrollable(&mut self, state: &mut dyn Scrollable, id: Option<&Id>) { - if Some(&self.target) == id { - state.snap_to(self.percentage); - } - } - fn container( &mut self, _id: Option<&Id>, @@ -29,7 +23,32 @@ pub fn snap_to<T>(target: Id, percentage: f32) -> impl Operation<T> { ) { operate_on_children(self) } + + fn scrollable(&mut self, state: &mut dyn Scrollable, id: Option<&Id>) { + if Some(&self.target) == id { + state.snap_to(self.offset); + } + } } - SnapTo { target, percentage } + SnapTo { target, offset } +} + +/// The amount of offset in each direction of a [`Scrollable`]. +/// +/// A value of `0.0` means start, while `1.0` means end. +#[derive(Debug, Clone, Copy, PartialEq, Default)] +pub struct RelativeOffset { + /// The amount of horizontal offset + pub x: f32, + /// The amount of vertical offset + pub y: f32, +} + +impl RelativeOffset { + /// A relative offset that points to the top-left of a [`Scrollable`]. + pub const START: Self = Self { x: 0.0, y: 0.0 }; + + /// A relative offset that points to the bottom-right of a [`Scrollable`]. + pub const END: Self = Self { x: 1.0, y: 1.0 }; } |