Rework Drag-And-Drop API (#4079)

* Add cursor position drag and drop events.
* Reword drag events to match pointer ones.
* appkit: Use `convertPoint_fromView` for coordinate conversion.
* appkit: use ProtocolObject<dyn NSDraggingInfo>.
* x11: store dnd.position as pair of i16

  It's what translate_coords takes anyway, so the extra precision is
  misleading if we're going to cast it to i16 everywhere it's used.

  We can also simplify the "unpacking" from the XdndPosition message--we
  can and should use the value of 16 as the shift instead of
  size_of::<c_short> * 2 or something like that, because the specification
  gives us the constant 16.
* x11: store translated DnD coords.
* x11: don't emit DragLeave without DragEnter.
* windows: only emit DragEnter if valid.
* windows: in DnD, always set pdwEffect.

  It appears other apps (like Chromium) set pdwEffect on Drop too:
  61a391b86b/ui/base/dragdrop/drop_target_win.cc
* docs: make it clearer that drag events are for dragged *files*.
* examples/dnd: handle RedrawRequested event.

Co-authored-by: amrbashir <amr.bashir2015@gmail.com>

examples/dnd.rs

@@ -0,0 +1,64 @@
+use std::error::Error;
+
+use winit::application::ApplicationHandler;
+use winit::event::WindowEvent;
+use winit::event_loop::{ActiveEventLoop, EventLoop};
+use winit::window::{Window, WindowAttributes, WindowId};
+
+#[path = "util/fill.rs"]
+mod fill;
+#[path = "util/tracing.rs"]
+mod tracing;
+
+fn main() -> Result<(), Box<dyn Error>> {
+    tracing::init();
+
+    let event_loop = EventLoop::new()?;
+
+    let app = Application::new();
+    Ok(event_loop.run_app(app)?)
+}
+
+/// Application state and event handling.
+struct Application {
+    window: Option<Box<dyn Window>>,
+}
+
+impl Application {
+    fn new() -> Self {
+        Self { window: None }
+    }
+}
+
+impl ApplicationHandler for Application {
+    fn can_create_surfaces(&mut self, event_loop: &dyn ActiveEventLoop) {
+        let window_attributes =
+            WindowAttributes::default().with_title("Drag and drop files on me!");
+        self.window = Some(event_loop.create_window(window_attributes).unwrap());
+    }
+
+    fn window_event(
+        &mut self,
+        event_loop: &dyn ActiveEventLoop,
+        _window_id: WindowId,
+        event: WindowEvent,
+    ) {
+        match event {
+            WindowEvent::DragLeft { .. }
+            | WindowEvent::DragEntered { .. }
+            | WindowEvent::DragMoved { .. }
+            | WindowEvent::DragDropped { .. } => {
+                println!("{:?}", event);
+            },
+            WindowEvent::RedrawRequested => {
+                let window = self.window.as_ref().unwrap();
+                window.pre_present_notify();
+                fill::fill_window(window.as_ref());
+            },
+            WindowEvent::CloseRequested => {
+                event_loop.exit();
+            },
+            _ => {},
+        }
+    }
+}

examples/window.rs

@@ -541,11 +541,12 @@ impl ApplicationHandler for Application {
                 info!("Smart zoom");
             },
             WindowEvent::TouchpadPressure { .. }
-            | WindowEvent::HoveredFileCancelled
+            | WindowEvent::DragLeft { .. }
             | WindowEvent::KeyboardInput { .. }
             | WindowEvent::PointerEntered { .. }
-            | WindowEvent::DroppedFile(_)
+            | WindowEvent::DragEntered { .. }
-            | WindowEvent::HoveredFile(_)
+            | WindowEvent::DragMoved { .. }
+            | WindowEvent::DragDropped { .. }
             | WindowEvent::Destroyed
             | WindowEvent::Moved(_) => (),
         }

src/changelog/unreleased.md

@@ -165,6 +165,25 @@ changelog entry.
 - Rename `VideoModeHandle` to `VideoMode`, now it only stores plain data.
 - Make `Fullscreen::Exclusive` contain `(MonitorHandle, VideoMode)`.
 - On Wayland, no longer send an explicit clearing `Ime::Preedit` just prior to a new `Ime::Preedit`.
+- Reworked the file drag-and-drop API.
+
+  The `WindowEvent::DroppedFile`, `WindowEvent::HoveredFile` and `WindowEvent::HoveredFileCancelled`
+  events have been removed, and replaced with `WindowEvent::DragEntered`, `WindowEvent::DragMoved`,
+  `WindowEvent::DragDropped` and `WindowEvent::DragLeft`.
+
+  The old drag-and-drop events were emitted once per file. This occurred when files were *first*
+  hovered over the window, dropped, or left the window. The new drag-and-drop events are emitted
+  once per set of files dragged, and include a list of all dragged files. They also include the
+  pointer position.
+
+  The rough correspondence is:
+  - `WindowEvent::HoveredFile` -> `WindowEvent::DragEntered`
+  - `WindowEvent::DroppedFile` -> `WindowEvent::DragDropped`
+  - `WindowEvent::HoveredFileCancelled` -> `WindowEvent::DragLeft`
+
+  The `WindowEvent::DragMoved` event is entirely new, and is emitted whenever the pointer moves
+  whilst files are being dragged over the window. It doesn't contain any file paths, just the
+  pointer position.
 
 ### Removed
 

src/event.rs

@@ -175,28 +175,42 @@ pub enum WindowEvent {
     /// The window has been destroyed.
     Destroyed,
 
-    /// A file is being hovered over the window.
+    /// A file drag operation has entered the window.
-    ///
+    DragEntered {
-    /// When the user hovers multiple files at once, this event will be emitted for each file
+        /// List of paths that are being dragged onto the window.
-    /// separately.
+        paths: Vec<PathBuf>,
-    HoveredFile(PathBuf),
+        /// (x,y) coordinates in pixels relative to the top-left corner of the window. May be
-
+        /// negative on some platforms if something is dragged over a window's decorations (title
-    /// A file has been dropped into the window.
+        /// bar, frame, etc).
-    ///
+        position: PhysicalPosition<f64>,
-    /// When the user drops multiple files at once, this event will be emitted for each file
+    },
-    /// separately.
+    /// A file drag operation has moved over the window.
-    ///
+    DragMoved {
-    /// The support for this is known to be incomplete, see [#720] for more
+        /// (x,y) coordinates in pixels relative to the top-left corner of the window. May be
-    /// information.
+        /// negative on some platforms if something is dragged over a window's decorations (title
-    ///
+        /// bar, frame, etc).
-    /// [#720]: https://github.com/rust-windowing/winit/issues/720
+        position: PhysicalPosition<f64>,
-    DroppedFile(PathBuf),
+    },
-
+    /// The file drag operation has dropped file(s) on the window.
-    /// A file was hovered, but has exited the window.
+    DragDropped {
-    ///
+        /// List of paths that are being dragged onto the window.
-    /// There will be a single `HoveredFileCancelled` event triggered even if multiple files were
+        paths: Vec<PathBuf>,
-    /// hovered.
+        /// (x,y) coordinates in pixels relative to the top-left corner of the window. May be
-    HoveredFileCancelled,
+        /// negative on some platforms if something is dragged over a window's decorations (title
+        /// bar, frame, etc).
+        position: PhysicalPosition<f64>,
+    },
+    /// The file drag operation has been cancelled or left the window.
+    DragLeft {
+        /// (x,y) coordinates in pixels relative to the top-left corner of the window. May be
+        /// negative on some platforms if something is dragged over a window's decorations (title
+        /// bar, frame, etc).
+        ///
+        /// ## Platform-specific
+        ///
+        /// - **Windows:** Always emits [`None`].
+        position: Option<PhysicalPosition<f64>>,
+    },
 
     /// The window gained or lost focus.
     ///
@@ -1221,9 +1235,16 @@ mod tests {
                 with_window_event(Focused(true));
                 with_window_event(Moved((0, 0).into()));
                 with_window_event(SurfaceResized((0, 0).into()));
-                with_window_event(DroppedFile("x.txt".into()));
+                with_window_event(DragEntered {
-                with_window_event(HoveredFile("x.txt".into()));
+                    paths: vec!["x.txt".into()],
-                with_window_event(HoveredFileCancelled);
+                    position: (0, 0).into(),
+                });
+                with_window_event(DragMoved { position: (0, 0).into() });
+                with_window_event(DragDropped {
+                    paths: vec!["x.txt".into()],
+                    position: (0, 0).into(),
+                });
+                with_window_event(DragLeft { position: Some((0, 0).into()) });
                 with_window_event(Ime(Enabled));
                 with_window_event(PointerMoved {
                     device_id: None,

src/platform_impl/apple/appkit/window_delegate.rs

@@ -13,7 +13,7 @@ use objc2::{declare_class, msg_send_id, mutability, sel, ClassType, DeclaredClas
 use objc2_app_kit::{
     NSAppKitVersionNumber, NSAppKitVersionNumber10_12, NSAppearance, NSAppearanceCustomization,
     NSAppearanceNameAqua, NSApplication, NSApplicationPresentationOptions, NSBackingStoreType,
-    NSColor, NSDraggingDestination, NSFilenamesPboardType, NSPasteboard,
+    NSColor, NSDraggingDestination, NSDraggingInfo, NSFilenamesPboardType,
     NSRequestUserAttentionType, NSScreen, NSToolbar, NSView, NSViewFrameDidChangeNotification,
     NSWindow, NSWindowButton, NSWindowDelegate, NSWindowFullScreenButton, NSWindowLevel,
     NSWindowOcclusionState, NSWindowOrderingMode, NSWindowSharingType, NSWindowStyleMask,
@@ -375,19 +375,45 @@ declare_class!(
     unsafe impl NSDraggingDestination for WindowDelegate {
         /// Invoked when the dragged image enters destination bounds or frame
         #[method(draggingEntered:)]
-        fn dragging_entered(&self, sender: &NSObject) -> bool {
+        fn dragging_entered(&self, sender: &ProtocolObject<dyn NSDraggingInfo>) -> bool {
             trace_scope!("draggingEntered:");
 
             use std::path::PathBuf;
 
-            let pb: Retained<NSPasteboard> = unsafe { msg_send_id![sender, draggingPasteboard] };
+            let pb = unsafe { sender.draggingPasteboard() };
             let filenames = pb.propertyListForType(unsafe { NSFilenamesPboardType }).unwrap();
             let filenames: Retained<NSArray<NSString>> = unsafe { Retained::cast(filenames) };
+            let paths = filenames
+                .into_iter()
+                .map(|file| PathBuf::from(file.to_string()))
+                .collect();
 
-            filenames.into_iter().for_each(|file| {
+            let dl = unsafe { sender.draggingLocation() };
-                let path = PathBuf::from(file.to_string());
+            let dl = self.view().convertPoint_fromView(dl, None);
-                self.queue_event(WindowEvent::HoveredFile(path));
+            let position = LogicalPosition::<f64>::from((dl.x, dl.y)).to_physical(self.scale_factor());
-            });
+
+
+            self.queue_event(WindowEvent::DragEntered { paths, position });
+
+            true
+        }
+
+        #[method(wantsPeriodicDraggingUpdates)]
+        fn wants_periodic_dragging_updates(&self) -> bool {
+            trace_scope!("wantsPeriodicDraggingUpdates:");
+            true
+        }
+
+        /// Invoked periodically as the image is held within the destination area, allowing modification of the dragging operation or mouse-pointer position.
+        #[method(draggingUpdated:)]
+        fn dragging_updated(&self, sender: &ProtocolObject<dyn NSDraggingInfo>) -> bool {
+            trace_scope!("draggingUpdated:");
+
+            let dl = unsafe { sender.draggingLocation() };
+            let dl = self.view().convertPoint_fromView(dl, None);
+            let position = LogicalPosition::<f64>::from((dl.x, dl.y)).to_physical(self.scale_factor());
+
+            self.queue_event(WindowEvent::DragMoved { position });
 
             true
         }
@@ -401,19 +427,24 @@ declare_class!(
 
         /// Invoked after the released image has been removed from the screen
         #[method(performDragOperation:)]
-        fn perform_drag_operation(&self, sender: &NSObject) -> bool {
+        fn perform_drag_operation(&self, sender: &ProtocolObject<dyn NSDraggingInfo>) -> bool {
             trace_scope!("performDragOperation:");
 
             use std::path::PathBuf;
 
-            let pb: Retained<NSPasteboard> = unsafe { msg_send_id![sender, draggingPasteboard] };
+            let pb = unsafe { sender.draggingPasteboard() };
             let filenames = pb.propertyListForType(unsafe { NSFilenamesPboardType }).unwrap();
             let filenames: Retained<NSArray<NSString>> = unsafe { Retained::cast(filenames) };
+            let paths = filenames
+                .into_iter()
+                .map(|file| PathBuf::from(file.to_string()))
+                .collect();
 
-            filenames.into_iter().for_each(|file| {
+            let dl = unsafe { sender.draggingLocation() };
-                let path = PathBuf::from(file.to_string());
+            let dl = self.view().convertPoint_fromView(dl, None);
-                self.queue_event(WindowEvent::DroppedFile(path));
+            let position = LogicalPosition::<f64>::from((dl.x, dl.y)).to_physical(self.scale_factor());
-            });
+
+            self.queue_event(WindowEvent::DragDropped { paths, position });
 
             true
         }
@@ -426,9 +457,16 @@ declare_class!(
 
         /// Invoked when the dragging operation is cancelled
         #[method(draggingExited:)]
-        fn dragging_exited(&self, _sender: Option<&NSObject>) {
+        fn dragging_exited(&self, info: Option<&ProtocolObject<dyn NSDraggingInfo>>) {
             trace_scope!("draggingExited:");
-            self.queue_event(WindowEvent::HoveredFileCancelled);
+
+            let position = info.map(|info| {
+                let dl = unsafe { info.draggingLocation() };
+                let dl = self.view().convertPoint_fromView(dl, None);
+                LogicalPosition::<f64>::from((dl.x, dl.y)).to_physical(self.scale_factor())
+            });
+
+            self.queue_event(WindowEvent::DragLeft { position } );
         }
     }
 

src/platform_impl/linux/x11/dnd.rs

@@ -4,6 +4,7 @@ use std::path::{Path, PathBuf};
 use std::str::Utf8Error;
 use std::sync::Arc;
 
+use dpi::PhysicalPosition;
 use percent_encoding::percent_decode;
 use x11rb::protocol::xproto::{self, ConnectionExt};
 
@@ -45,13 +46,25 @@ pub struct Dnd {
     pub type_list: Option<Vec<xproto::Atom>>,
     // Populated by XdndPosition event handler
     pub source_window: Option<xproto::Window>,
+    // Populated by XdndPosition event handler
+    pub position: PhysicalPosition<f64>,
     // Populated by SelectionNotify event handler (triggered by XdndPosition event handler)
     pub result: Option<Result<Vec<PathBuf>, DndDataParseError>>,
+    // Populated by SelectionNotify event handler (triggered by XdndPosition event handler)
+    pub dragging: bool,
 }
 
 impl Dnd {
     pub fn new(xconn: Arc<XConnection>) -> Result<Self, X11Error> {
-        Ok(Dnd { xconn, version: None, type_list: None, source_window: None, result: None })
+        Ok(Dnd {
+            xconn,
+            version: None,
+            type_list: None,
+            source_window: None,
+            position: PhysicalPosition::default(),
+            result: None,
+            dragging: false,
+        })
     }
 
     pub fn reset(&mut self) {
@@ -59,6 +72,7 @@ impl Dnd {
         self.type_list = None;
         self.source_window = None;
         self.result = None;
+        self.dragging = false;
     }
 
     pub unsafe fn send_status(

src/platform_impl/linux/x11/event_processor.rs

@@ -470,14 +470,19 @@ impl EventProcessor {
 
             let source_window = xev.data.get_long(0) as xproto::Window;
 
-            // Equivalent to `(x << shift) | y`
+            // https://www.freedesktop.org/wiki/Specifications/XDND/#xdndposition
-            // where `shift = mem::size_of::<c_short>() * 8`
             // Note that coordinates are in "desktop space", not "window space"
             // (in X11 parlance, they're root window coordinates)
-            // let packed_coordinates = xev.data.get_long(2);
+            let packed_coordinates = xev.data.get_long(2);
-            // let shift = mem::size_of::<libc::c_short>() * 8;
+            let x = (packed_coordinates >> 16) as i16;
-            // let x = packed_coordinates >> shift;
+            let y = (packed_coordinates & 0xffff) as i16;
-            // let y = packed_coordinates & !(x << shift);
+
+            let coords = self
+                .target
+                .xconn
+                .translate_coords(self.target.root, window, x, y)
+                .expect("Failed to translate window coordinates");
+            self.dnd.position = PhysicalPosition::new(coords.dst_x as f64, coords.dst_y as f64);
 
             // By our own state flow, `version` should never be `None` at this point.
             let version = self.dnd.version.unwrap_or(5);
@@ -502,21 +507,19 @@ impl EventProcessor {
             }
 
             self.dnd.source_window = Some(source_window);
-            if self.dnd.result.is_none() {
+            let time = if version == 0 {
-                let time = if version >= 1 {
+                // In version 0, time isn't specified
-                    xev.data.get_long(3) as xproto::Timestamp
+                x11rb::CURRENT_TIME
-                } else {
+            } else {
-                    // In version 0, time isn't specified
+                xev.data.get_long(3) as xproto::Timestamp
-                    x11rb::CURRENT_TIME
+            };
-                };
 
-                // Log this timestamp.
+            // Log this timestamp.
-                self.target.xconn.set_timestamp(time);
+            self.target.xconn.set_timestamp(time);
 
-                // This results in the `SelectionNotify` event below
+            // This results in the `SelectionNotify` event below
-                unsafe {
+            unsafe {
-                    self.dnd.convert_selection(window, time);
+                self.dnd.convert_selection(window, time);
-                }
             }
 
             unsafe {
@@ -530,13 +533,12 @@ impl EventProcessor {
         if xev.message_type == atoms[XdndDrop] as c_ulong {
             let (source_window, state) = if let Some(source_window) = self.dnd.source_window {
                 if let Some(Ok(ref path_list)) = self.dnd.result {
-                    for path in path_list {
+                    let event = WindowEvent::DragDropped {
-                        let event = Event::WindowEvent {
+                        paths: path_list.iter().map(Into::into).collect(),
-                            window_id,
+                        position: self.dnd.position,
-                            event: WindowEvent::DroppedFile(path.clone()),
+                    };
-                        };
+
-                        callback(&self.target, event);
+                    callback(&self.target, Event::WindowEvent { window_id, event });
-                    }
                 }
                 (source_window, DndState::Accepted)
             } else {
@@ -557,9 +559,14 @@ impl EventProcessor {
         }
 
         if xev.message_type == atoms[XdndLeave] as c_ulong {
+            if self.dnd.dragging {
+                let event = Event::WindowEvent {
+                    window_id,
+                    event: WindowEvent::DragLeft { position: Some(self.dnd.position) },
+                };
+                callback(&self.target, event);
+            }
             self.dnd.reset();
-            let event = Event::WindowEvent { window_id, event: WindowEvent::HoveredFileCancelled };
-            callback(&self.target, event);
         }
     }
 
@@ -583,15 +590,19 @@ impl EventProcessor {
         self.dnd.result = None;
         if let Ok(mut data) = unsafe { self.dnd.read_data(window) } {
             let parse_result = self.dnd.parse_data(&mut data);
+
             if let Ok(ref path_list) = parse_result {
-                for path in path_list {
+                let event = if self.dnd.dragging {
-                    let event = Event::WindowEvent {
+                    WindowEvent::DragMoved { position: self.dnd.position }
-                        window_id,
+                } else {
-                        event: WindowEvent::HoveredFile(path.clone()),
+                    let paths = path_list.iter().map(Into::into).collect();
-                    };
+                    self.dnd.dragging = true;
-                    callback(&self.target, event);
+                    WindowEvent::DragEntered { paths, position: self.dnd.position }
-                }
+                };
+
+                callback(&self.target, Event::WindowEvent { window_id, event });
             }
+
             self.dnd.result = Some(parse_result);
         }
     }

src/platform_impl/linux/x11/util/geometry.rs

@@ -95,7 +95,7 @@ impl FrameExtentsHeuristic {
 
 impl XConnection {
     // This is adequate for inner_position
-    pub fn translate_coords(
+    pub fn translate_coords_root(
         &self,
         window: xproto::Window,
         root: xproto::Window,
@@ -103,6 +103,19 @@ impl XConnection {
         self.xcb_connection().translate_coordinates(window, root, 0, 0)?.reply().map_err(Into::into)
     }
 
+    pub fn translate_coords(
+        &self,
+        src_w: xproto::Window,
+        dst_w: xproto::Window,
+        src_x: i16,
+        src_y: i16,
+    ) -> Result<xproto::TranslateCoordinatesReply, X11Error> {
+        self.xcb_connection()
+            .translate_coordinates(src_w, dst_w, src_x, src_y)?
+            .reply()
+            .map_err(Into::into)
+    }
+
     // This is adequate for surface_size
     pub fn get_geometry(
         &self,
@@ -189,7 +202,7 @@ impl XConnection {
         // that, fullscreen windows often aren't nested.
         let (inner_y_rel_root, child) = {
             let coords = self
-                .translate_coords(window, root)
+                .translate_coords_root(window, root)
                 .expect("Failed to translate window coordinates");
             (coords.dst_y, coords.child)
         };

src/platform_impl/linux/x11/window.rs

@@ -1520,7 +1520,7 @@ impl UnownedWindow {
         // This should be okay to unwrap since the only error XTranslateCoordinates can return
         // is BadWindow, and if the window handle is bad we have bigger problems.
         self.xconn
-            .translate_coords(self.xwindow, self.root)
+            .translate_coords_root(self.xwindow, self.root)
             .map(|coords| (coords.dst_x.into(), coords.dst_y.into()))
             .unwrap()
     }

src/platform_impl/windows/definitions.rs

@@ -72,13 +72,13 @@ pub struct IDropTargetVtbl {
         This: *mut IDropTarget,
         pDataObj: *const IDataObject,
         grfKeyState: u32,
-        pt: *const POINTL,
+        pt: POINTL,
         pdwEffect: *mut u32,
     ) -> HRESULT,
     pub DragOver: unsafe extern "system" fn(
         This: *mut IDropTarget,
         grfKeyState: u32,
-        pt: *const POINTL,
+        pt: POINTL,
         pdwEffect: *mut u32,
     ) -> HRESULT,
     pub DragLeave: unsafe extern "system" fn(This: *mut IDropTarget) -> HRESULT,
@@ -86,7 +86,7 @@ pub struct IDropTargetVtbl {
         This: *mut IDropTarget,
         pDataObj: *const IDataObject,
         grfKeyState: u32,
-        pt: *const POINTL,
+        pt: POINTL,
         pdwEffect: *mut u32,
     ) -> HRESULT,
 }

src/platform_impl/windows/drop_handler.rs

@@ -6,12 +6,14 @@ use std::sync::atomic::{AtomicUsize, Ordering};
 
 use tracing::debug;
 use windows_sys::core::{IUnknown, GUID, HRESULT};
-use windows_sys::Win32::Foundation::{DV_E_FORMATETC, HWND, POINTL, S_OK};
+use windows_sys::Win32::Foundation::{DV_E_FORMATETC, HWND, POINT, POINTL, S_OK};
+use windows_sys::Win32::Graphics::Gdi::ScreenToClient;
 use windows_sys::Win32::System::Com::{IDataObject, DVASPECT_CONTENT, FORMATETC, TYMED_HGLOBAL};
 use windows_sys::Win32::System::Ole::{CF_HDROP, DROPEFFECT_COPY, DROPEFFECT_NONE};
 use windows_sys::Win32::UI::Shell::{DragFinish, DragQueryFileW, HDROP};
 
-use crate::event::Event;
+use crate::dpi::PhysicalPosition;
+use crate::event::{Event, WindowEvent};
 use crate::platform_impl::platform::definitions::{
     IDataObjectVtbl, IDropTarget, IDropTargetVtbl, IUnknownVtbl,
 };
@@ -24,8 +26,8 @@ pub struct FileDropHandlerData {
     window: HWND,
     send_event: Box<dyn Fn(Event)>,
     cursor_effect: u32,
-    hovered_is_valid: bool, /* If the currently hovered item is not valid there must not be any
+    valid: bool, /* If the currently hovered item is not valid there must not be any
-                             * `HoveredFileCancelled` emitted */
+                  * `DragLeft` emitted */
 }
 
 pub struct FileDropHandler {
@@ -41,7 +43,7 @@ impl FileDropHandler {
             window,
             send_event,
             cursor_effect: DROPEFFECT_NONE,
-            hovered_is_valid: false,
+            valid: false,
         });
         FileDropHandler { data: Box::into_raw(data) }
     }
@@ -77,22 +79,26 @@ impl FileDropHandler {
         this: *mut IDropTarget,
         pDataObj: *const IDataObject,
         _grfKeyState: u32,
-        _pt: *const POINTL,
+        pt: POINTL,
         pdwEffect: *mut u32,
     ) -> HRESULT {
-        use crate::event::WindowEvent::HoveredFile;
         let drop_handler = unsafe { Self::from_interface(this) };
-        let hdrop = unsafe {
+        let mut pt = POINT { x: pt.x, y: pt.y };
-            Self::iterate_filenames(pDataObj, |filename| {
+        unsafe {
-                drop_handler.send_event(Event::WindowEvent {
+            ScreenToClient(drop_handler.window, &mut pt);
-                    window_id: WindowId::from_raw(drop_handler.window as usize),
+        }
-                    event: HoveredFile(filename),
+        let position = PhysicalPosition::new(pt.x as f64, pt.y as f64);
-                });
+        let mut paths = Vec::new();
-            })
+        let hdrop = unsafe { Self::iterate_filenames(pDataObj, |path| paths.push(path)) };
-        };
+        drop_handler.valid = hdrop.is_some();
-        drop_handler.hovered_is_valid = hdrop.is_some();
+        if drop_handler.valid {
+            drop_handler.send_event(Event::WindowEvent {
+                window_id: WindowId::from_raw(drop_handler.window as usize),
+                event: WindowEvent::DragEntered { paths, position },
+            });
+        }
         drop_handler.cursor_effect =
-            if drop_handler.hovered_is_valid { DROPEFFECT_COPY } else { DROPEFFECT_NONE };
+            if drop_handler.valid { DROPEFFECT_COPY } else { DROPEFFECT_NONE };
         unsafe {
             *pdwEffect = drop_handler.cursor_effect;
         }
@@ -103,10 +109,21 @@ impl FileDropHandler {
     pub unsafe extern "system" fn DragOver(
         this: *mut IDropTarget,
         _grfKeyState: u32,
-        _pt: *const POINTL,
+        pt: POINTL,
         pdwEffect: *mut u32,
     ) -> HRESULT {
         let drop_handler = unsafe { Self::from_interface(this) };
+        if drop_handler.valid {
+            let mut pt = POINT { x: pt.x, y: pt.y };
+            unsafe {
+                ScreenToClient(drop_handler.window, &mut pt);
+            }
+            let position = PhysicalPosition::new(pt.x as f64, pt.y as f64);
+            drop_handler.send_event(Event::WindowEvent {
+                window_id: WindowId::from_raw(drop_handler.window as usize),
+                event: WindowEvent::DragMoved { position },
+            });
+        }
         unsafe {
             *pdwEffect = drop_handler.cursor_effect;
         }
@@ -115,12 +132,11 @@ impl FileDropHandler {
     }
 
     pub unsafe extern "system" fn DragLeave(this: *mut IDropTarget) -> HRESULT {
-        use crate::event::WindowEvent::HoveredFileCancelled;
         let drop_handler = unsafe { Self::from_interface(this) };
-        if drop_handler.hovered_is_valid {
+        if drop_handler.valid {
             drop_handler.send_event(Event::WindowEvent {
                 window_id: WindowId::from_raw(drop_handler.window as usize),
-                event: HoveredFileCancelled,
+                event: WindowEvent::DragLeft { position: None },
             });
         }
 
@@ -131,21 +147,30 @@ impl FileDropHandler {
         this: *mut IDropTarget,
         pDataObj: *const IDataObject,
         _grfKeyState: u32,
-        _pt: *const POINTL,
+        pt: POINTL,
-        _pdwEffect: *mut u32,
+        pdwEffect: *mut u32,
     ) -> HRESULT {
-        use crate::event::WindowEvent::DroppedFile;
         let drop_handler = unsafe { Self::from_interface(this) };
-        let hdrop = unsafe {
+        if drop_handler.valid {
-            Self::iterate_filenames(pDataObj, |filename| {
+            let mut pt = POINT { x: pt.x, y: pt.y };
-                drop_handler.send_event(Event::WindowEvent {
+            unsafe {
-                    window_id: WindowId::from_raw(drop_handler.window as usize),
+                ScreenToClient(drop_handler.window, &mut pt);
-                    event: DroppedFile(filename),
+            }
-                });
+            let position = PhysicalPosition::new(pt.x as f64, pt.y as f64);
-            })
+            let mut paths = Vec::new();
-        };
+            let hdrop = unsafe { Self::iterate_filenames(pDataObj, |path| paths.push(path)) };
-        if let Some(hdrop) = hdrop {
+            drop_handler.send_event(Event::WindowEvent {
-            unsafe { DragFinish(hdrop) };
+                window_id: WindowId::from_raw(drop_handler.window as usize),
+                event: WindowEvent::DragDropped { paths, position },
+            });
+            if let Some(hdrop) = hdrop {
+                unsafe {
+                    DragFinish(hdrop);
+                }
+            }
+        }
+        unsafe {
+            *pdwEffect = drop_handler.cursor_effect;
         }
 
         S_OK
@@ -155,9 +180,9 @@ impl FileDropHandler {
         unsafe { &mut *(this as *mut _) }
     }
 
-    unsafe fn iterate_filenames<F>(data_obj: *const IDataObject, callback: F) -> Option<HDROP>
+    unsafe fn iterate_filenames<F>(data_obj: *const IDataObject, mut callback: F) -> Option<HDROP>
     where
-        F: Fn(PathBuf),
+        F: FnMut(PathBuf),
     {
         let drop_format = FORMATETC {
             cfFormat: CF_HDROP,