adjust scroll offset

glutin/src/application.rs

@@ -1,5 +1,5 @@
 //! Create interactive, native cross-platform applications.
-use crate::{mouse, Error, Executor, Runtime};
+use crate::{mouse, Error, Executor, Runtime, Vector};
 
 pub use iced_winit::Application;
 
@@ -187,6 +187,7 @@ async fn run_instance<A, E, C>(
                 let statuses = user_interface.update(
                     &events,
                     state.cursor_position(),
+                    Vector::new(0.0, 0.0),
                     &mut renderer,
                     &mut clipboard,
                     &mut messages,

native/src/element.rs

@@ -1,6 +1,6 @@
 use crate::event::{self, Event};
-use crate::layout;
 use crate::overlay;
+use crate::{layout, Vector};
 use crate::{
     Clipboard, Color, Hasher, Layout, Length, Point, Rectangle, Widget,
 };
@@ -223,6 +223,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -231,6 +232,7 @@ where
             event,
             layout,
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             messages,
@@ -311,6 +313,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<B>,
@@ -321,6 +324,7 @@ where
             event,
             layout,
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             &mut original_messages,
@@ -401,6 +405,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -409,6 +414,7 @@ where
             event,
             layout,
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             messages,

native/src/overlay.rs

@@ -7,7 +7,7 @@ pub use element::Element;
 pub use menu::Menu;
 
 use crate::event::{self, Event};
-use crate::layout;
+use crate::{layout, Vector};
 use crate::{Clipboard, Hasher, Layout, Point, Size};
 
 /// An interactive component that can be displayed on top of other widgets.
@@ -67,6 +67,7 @@ where
         _event: Event,
         _layout: Layout<'_>,
         _cursor_position: Point,
+        _scroll_offset: Vector<f32>,
         _renderer: &Renderer,
         _clipboard: &mut dyn Clipboard,
         _messages: &mut Vec<Message>,

native/src/overlay/element.rs

@@ -53,6 +53,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -61,6 +62,7 @@ where
             event,
             layout,
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             messages,
@@ -117,6 +119,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<B>,
@@ -127,6 +130,7 @@ where
             event,
             layout,
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             &mut original_messages,

native/src/overlay/menu.rs

@@ -219,6 +219,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -227,6 +228,7 @@ where
             event.clone(),
             layout,
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             messages,
@@ -320,6 +322,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        _scroll_offset: Vector<f32>,
         renderer: &Renderer,
         _clipboard: &mut dyn Clipboard,
         _messages: &mut Vec<Message>,

native/src/program/state.rs

@@ -1,5 +1,6 @@
 use crate::{
-    Cache, Command, Debug, Event, Point, Program, Renderer, Size, UserInterface,
+    Cache, Command, Debug, Event, Point, Program, Renderer, Size,
+    UserInterface, Vector,
 };
 
 /// The execution state of a [`Program`]. It leverages caching, event
@@ -90,6 +91,7 @@ where
         &mut self,
         bounds: Size,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &mut P::Renderer,
         clipboard: &mut P::Clipboard,
         debug: &mut Debug,
@@ -108,6 +110,7 @@ where
         let _ = user_interface.update(
             &self.queued_events,
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             &mut messages,

native/src/user_interface.rs

@@ -1,6 +1,6 @@
 use crate::event::{self, Event};
-use crate::layout;
 use crate::overlay;
+use crate::{layout, Vector};
 use crate::{Clipboard, Element, Layout, Point, Rectangle, Size};
 
 use std::hash::Hasher;
@@ -194,6 +194,7 @@ where
         &mut self,
         events: &[Event],
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -216,6 +217,7 @@ where
                         event,
                         Layout::new(&layer.layout),
                         cursor_position,
+                        scroll_offset,
                         renderer,
                         clipboard,
                         messages,
@@ -247,6 +249,7 @@ where
                     event,
                     Layout::new(&self.base.layout),
                     base_cursor,
+                    Vector::new(0.0, 0.0),
                     renderer,
                     clipboard,
                     messages,

native/src/widget.rs

@@ -79,8 +79,8 @@ pub use toggler::Toggler;
 pub use tooltip::Tooltip;
 
 use crate::event::{self, Event};
-use crate::layout;
 use crate::overlay;
+use crate::{layout, Vector};
 use crate::{Clipboard, Hasher, Layout, Length, Point, Rectangle};
 
 /// A component that displays information and allows interaction.
@@ -167,6 +167,7 @@ where
         _event: Event,
         _layout: Layout<'_>,
         _cursor_position: Point,
+        _scroll_offset: Vector<f32>,
         _renderer: &Renderer,
         _clipboard: &mut dyn Clipboard,
         _messages: &mut Vec<Message>,

native/src/widget/button.rs

@@ -2,14 +2,16 @@
 //!
 //! A [`Button`] has some local [`State`].
 use crate::event::{self, Event};
-use crate::layout;
 use crate::mouse;
 use crate::overlay;
 use crate::touch;
+use crate::touch::Finger;
+use crate::{layout, Vector};
 use crate::{
     Clipboard, Element, Hasher, Layout, Length, Padding, Point, Rectangle,
     Widget,
 };
+use std::collections::HashSet;
 use std::hash::Hash;
 
 /// A generic widget that produces a message when pressed.
@@ -63,6 +65,7 @@ pub struct Button<'a, Message, Renderer: self::Renderer> {
     min_height: u32,
     padding: Padding,
     style: Renderer::Style,
+    fingers_mid_press: HashSet<Finger>,
 }
 
 impl<'a, Message, Renderer> Button<'a, Message, Renderer>
@@ -86,6 +89,8 @@ where
             min_height: 0,
             padding: Renderer::DEFAULT_PADDING,
             style: Renderer::Style::default(),
+
+            fingers_mid_press: HashSet::with_capacity(2),
         }
     }
 
@@ -188,6 +193,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -196,6 +202,7 @@ where
             event.clone(),
             layout.children().next().unwrap(),
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             messages,
@@ -204,8 +211,7 @@ where
         }
 
         match event {
-            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left))
-            | Event::Touch(touch::Event::FingerPressed { .. }) => {
+            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left)) => {
                 if self.on_press.is_some() {
                     let bounds = layout.bounds();
 
@@ -216,8 +222,7 @@ where
                     }
                 }
             }
-            Event::Mouse(mouse::Event::ButtonReleased(mouse::Button::Left))
-            | Event::Touch(touch::Event::FingerLifted { .. }) => {
+            Event::Mouse(mouse::Event::ButtonReleased(mouse::Button::Left)) => {
                 if let Some(on_press) = self.on_press.clone() {
                     let bounds = layout.bounds();
 
@@ -232,8 +237,46 @@ where
                     }
                 }
             }
-            Event::Touch(touch::Event::FingerLost { .. }) => {
-                self.state.is_pressed = false;
+            Event::Touch(x) => {
+                eprintln!(
+                    "B {:?} Bds {:?} P {:?}",
+                    x,
+                    layout.bounds(),
+                    self.fingers_mid_press
+                );
+                match x {
+                    touch::Event::FingerPressed { id, position } => {
+                        if layout.bounds().contains(position + scroll_offset) {
+                            eprintln!("ins");
+                            let _ = self.fingers_mid_press.insert(id);
+
+                            return event::Status::Captured;
+                        }
+                    }
+                    touch::Event::FingerMoved { id, position } => {
+                        if !layout.bounds().contains(position + scroll_offset) {
+                            eprintln!("exited");
+                            let _ = self.fingers_mid_press.remove(&id);
+                        } else {
+                            return event::Status::Captured;
+                        }
+                    }
+                    touch::Event::FingerLifted { id, .. } => {
+                        // !!! The finger position seems to be buggy on the Lift event.
+                        if self.fingers_mid_press.remove(&id) {
+                            eprintln!("lifted");
+                            // this should be treated as a click
+                            if let Some(on_press) = self.on_press.clone() {
+                                messages.push(on_press);
+                            }
+
+                            return event::Status::Captured;
+                        }
+                    }
+                    touch::Event::FingerLost { id, .. } => {
+                        let _ = self.fingers_mid_press.remove(&id);
+                    }
+                }
             }
             _ => {}
         }

native/src/widget/checkbox.rs

@@ -2,11 +2,11 @@
 use std::hash::Hash;
 
 use crate::event::{self, Event};
-use crate::layout;
 use crate::mouse;
 use crate::row;
 use crate::text;
 use crate::touch;
+use crate::{layout, Vector};
 use crate::{
     Align, Clipboard, Color, Element, Hasher, HorizontalAlignment, Layout,
     Length, Point, Rectangle, Row, Text, VerticalAlignment, Widget,
@@ -158,6 +158,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        _scroll_offset: Vector<f32>,
         _renderer: &Renderer,
         _clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,

native/src/widget/column.rs

@@ -2,8 +2,8 @@
 use std::hash::Hash;
 
 use crate::event::{self, Event};
-use crate::layout;
 use crate::overlay;
+use crate::{layout, Vector};
 use crate::{
     Align, Clipboard, Element, Hasher, Layout, Length, Padding, Point,
     Rectangle, Widget,
@@ -142,6 +142,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -154,6 +155,7 @@ where
                     event.clone(),
                     layout,
                     cursor_position,
+                    scroll_offset,
                     renderer,
                     clipboard,
                     messages,

native/src/widget/container.rs

@@ -2,8 +2,8 @@
 use std::hash::Hash;
 
 use crate::event::{self, Event};
-use crate::layout;
 use crate::overlay;
+use crate::{layout, Vector};
 use crate::{
     Align, Clipboard, Element, Hasher, Layout, Length, Padding, Point,
     Rectangle, Widget,
@@ -153,6 +153,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -161,6 +162,7 @@ where
             event,
             layout.children().next().unwrap(),
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             messages,

native/src/widget/image/viewer.rs

@@ -155,6 +155,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        _scroll_offset: Vector<f32>,
         renderer: &Renderer,
         _clipboard: &mut dyn Clipboard,
         _messages: &mut Vec<Message>,

native/src/widget/pane_grid.rs

@@ -362,6 +362,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -461,6 +462,7 @@ where
                         event.clone(),
                         layout,
                         cursor_position,
+                        scroll_offset,
                         renderer,
                         clipboard,
                         messages,

native/src/widget/pane_grid/content.rs

@@ -1,8 +1,8 @@
-use crate::container;
 use crate::event::{self, Event};
 use crate::layout;
 use crate::overlay;
 use crate::pane_grid::{self, TitleBar};
+use crate::{container, Vector};
 use crate::{Clipboard, Element, Hasher, Layout, Point, Rectangle, Size};
 
 /// The content of a [`Pane`].
@@ -146,6 +146,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -159,6 +160,7 @@ where
                 event.clone(),
                 children.next().unwrap(),
                 cursor_position,
+                scroll_offset,
                 renderer,
                 clipboard,
                 messages,
@@ -173,6 +175,7 @@ where
             event,
             body_layout,
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             messages,

native/src/widget/pane_grid/title_bar.rs

@@ -1,8 +1,8 @@
-use crate::container;
 use crate::event::{self, Event};
 use crate::layout;
 use crate::overlay;
 use crate::pane_grid;
+use crate::{container, Vector};
 use crate::{
     Clipboard, Element, Hasher, Layout, Padding, Point, Rectangle, Size,
 };
@@ -207,6 +207,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -224,6 +225,7 @@ where
                 event.clone(),
                 controls_layout,
                 cursor_position,
+                scroll_offset,
                 renderer,
                 clipboard,
                 messages,
@@ -236,6 +238,7 @@ where
             event,
             title_layout,
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             messages,

native/src/widget/pick_list.rs

@@ -1,12 +1,12 @@
 //! Display a dropdown list of selectable values.
 use crate::event::{self, Event};
-use crate::layout;
 use crate::mouse;
 use crate::overlay;
 use crate::overlay::menu::{self, Menu};
 use crate::scrollable;
 use crate::text;
 use crate::touch;
+use crate::{layout, Vector};
 use crate::{
     Clipboard, Element, Hasher, Layout, Length, Padding, Point, Rectangle,
     Size, Widget,
@@ -211,6 +211,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        _scroll_offset: Vector<f32>,
         _renderer: &Renderer,
         _clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,

native/src/widget/radio.rs

@@ -2,11 +2,11 @@
 use std::hash::Hash;
 
 use crate::event::{self, Event};
-use crate::mouse;
 use crate::row;
 use crate::text;
 use crate::touch;
 use crate::{layout, Color};
+use crate::{mouse, Vector};
 use crate::{
     Align, Clipboard, Element, Hasher, HorizontalAlignment, Layout, Length,
     Point, Rectangle, Row, Text, VerticalAlignment, Widget,
@@ -172,6 +172,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        _scroll_offset: Vector<f32>,
         _renderer: &Renderer,
         _clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,

native/src/widget/row.rs

@@ -1,7 +1,7 @@
 //! Distribute content horizontally.
 use crate::event::{self, Event};
-use crate::layout;
 use crate::overlay;
+use crate::{layout, Vector};
 use crate::{
     Align, Clipboard, Element, Hasher, Layout, Length, Padding, Point,
     Rectangle, Widget,
@@ -141,6 +141,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -153,6 +154,7 @@ where
                     event.clone(),
                     layout,
                     cursor_position,
+                    scroll_offset,
                     renderer,
                     clipboard,
                     messages,

native/src/widget/scrollable.rs

@@ -192,6 +192,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -235,6 +236,7 @@ where
                 event.clone(),
                 content,
                 cursor_position,
+                scroll_offset + Vector::new(0.0, self.state.offset.absolute(bounds, content_bounds)),
                 renderer,
                 clipboard,
                 messages,

native/src/widget/slider.rs

@@ -2,9 +2,9 @@
 //!
 //! A [`Slider`] has some local [`State`].
 use crate::event::{self, Event};
-use crate::layout;
 use crate::mouse;
 use crate::touch;
+use crate::{layout, Vector};
 use crate::{
     Clipboard, Element, Hasher, Layout, Length, Point, Rectangle, Size, Widget,
 };
@@ -180,6 +180,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        _scroll_offset: Vector<f32>,
         _renderer: &Renderer,
         _clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,

native/src/widget/text_input.rs

@@ -12,11 +12,11 @@ pub use value::Value;
 use editor::Editor;
 
 use crate::event::{self, Event};
-use crate::keyboard;
 use crate::layout;
 use crate::mouse::{self, click};
 use crate::text;
 use crate::touch;
+use crate::{keyboard, Vector};
 use crate::{
     Clipboard, Element, Hasher, Layout, Length, Padding, Point, Rectangle,
     Size, Widget,
@@ -246,6 +246,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        _scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,

native/src/widget/toggler.rs

@@ -1,11 +1,13 @@
 //! Show toggle controls using togglers.
 use std::hash::Hash;
 
+use crate::touch::Finger;
 use crate::{
-    event, layout, mouse, row, text, Align, Clipboard, Element, Event, Hasher,
-    HorizontalAlignment, Layout, Length, Point, Rectangle, Row, Text,
-    VerticalAlignment, Widget,
+    event, layout, mouse, row, text, touch, Align, Clipboard, Element, Event,
+    Hasher, HorizontalAlignment, Layout, Length, Point, Rectangle, Row, Text,
+    Vector, VerticalAlignment, Widget,
 };
+use std::collections::HashSet;
 
 /// A toggler widget
 ///
@@ -34,6 +36,8 @@ pub struct Toggler<Message, Renderer: self::Renderer + text::Renderer> {
     spacing: u16,
     font: Renderer::Font,
     style: Renderer::Style,
+
+    fingers_mid_press: HashSet<Finger>,
 }
 
 impl<Message, Renderer: self::Renderer + text::Renderer>
@@ -66,6 +70,8 @@ impl<Message, Renderer: self::Renderer + text::Renderer>
             spacing: 0,
             font: Renderer::Font::default(),
             style: Renderer::Style::default(),
+
+            fingers_mid_press: HashSet::with_capacity(2),
         }
     }
 
@@ -158,6 +164,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         _renderer: &Renderer,
         _clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -174,6 +181,45 @@ where
                     event::Status::Ignored
                 }
             }
+            Event::Touch(x) => {
+                match x {
+                    touch::Event::FingerPressed { id, position } => {
+                        if layout.bounds().contains(position + scroll_offset) {
+                            let _ = self.fingers_mid_press.insert(id);
+
+                            event::Status::Captured
+                        } else {
+                            event::Status::Ignored
+                        }
+                    }
+                    touch::Event::FingerMoved { id, position } => {
+                        if !layout.bounds().contains(position + scroll_offset) {
+                            let _ = self.fingers_mid_press.remove(&id);
+
+                            event::Status::Captured
+                        } else {
+                            event::Status::Ignored
+                        }
+                    }
+                    touch::Event::FingerLifted { id, .. } => {
+                        // !!! The finger position seems to be buggy on the Lift event.
+                        if self.fingers_mid_press.remove(&id)
+                        // && layout.bounds().contains(position)
+                        {
+                            // this should be treated as a click
+                            messages.push((self.on_toggle)(!self.is_active));
+
+                            event::Status::Captured
+                        } else {
+                            event::Status::Ignored
+                        }
+                    }
+                    touch::Event::FingerLost { id, .. } => {
+                        let _ = self.fingers_mid_press.remove(&id);
+                        event::Status::Ignored
+                    }
+                }
+            }
             _ => event::Status::Ignored,
         }
     }

native/src/widget/tooltip.rs

@@ -7,7 +7,7 @@ use crate::widget::container;
 use crate::widget::text::{self, Text};
 use crate::{
     event, layout, Clipboard, Element, Event, Hasher, Layout, Length, Point,
-    Widget,
+    Vector, Widget,
 };
 
 /// An element to display a widget over another.
@@ -120,6 +120,7 @@ where
         event: Event,
         layout: Layout<'_>,
         cursor_position: Point,
+        scroll_offset: Vector<f32>,
         renderer: &Renderer,
         clipboard: &mut dyn Clipboard,
         messages: &mut Vec<Message>,
@@ -128,6 +129,7 @@ where
             event,
             layout,
             cursor_position,
+            scroll_offset,
             renderer,
             clipboard,
             messages,

winit/src/application.rs

@@ -3,8 +3,8 @@ mod state;
 
 pub use state::State;
 
-use crate::conversion;
 use crate::mouse;
+use crate::{conversion, Vector};
 use crate::{
     Clipboard, Color, Command, Debug, Error, Executor, Mode, Proxy, Runtime,
     Settings, Size, Subscription,
@@ -261,6 +261,7 @@ async fn run_instance<A, E, C>(
                 let statuses = user_interface.update(
                     &events,
                     state.cursor_position(),
+                    Vector::new(0.0, 0.0),
                     &mut renderer,
                     &mut clipboard,
                     &mut messages,