From 76cdbe2cf8ebb946377c51f4545b27033d335096 Mon Sep 17 00:00:00 2001
From: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Date: Thu, 30 Sep 2021 19:40:21 +0200
Subject: [PATCH] Add better documentation for
 epi::NativeOptions::drag_and_drop_support

Closes https://github.com/emilk/egui/issues/747
---
 eframe/examples/file_dialog.rs | 5 ++++-
 egui/src/data/input.rs         | 3 +++
 egui_demo_app/src/main.rs      | 1 +
 epi/src/lib.rs                 | 5 +++--
 4 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/eframe/examples/file_dialog.rs b/eframe/examples/file_dialog.rs
index 91585c4f..2de6e3f4 100644
--- a/eframe/examples/file_dialog.rs
+++ b/eframe/examples/file_dialog.rs
@@ -95,6 +95,9 @@ impl MyApp {
 }
 
 fn main() {
-    let options = eframe::NativeOptions::default();
+    let options = eframe::NativeOptions {
+        drag_and_drop_support: true,
+        ..Default::default()
+    };
     eframe::run_native(Box::new(MyApp::default()), options);
 }
diff --git a/egui/src/data/input.rs b/egui/src/data/input.rs
index 07ebfd38..89f42bf0 100644
--- a/egui/src/data/input.rs
+++ b/egui/src/data/input.rs
@@ -60,6 +60,9 @@ pub struct RawInput {
     pub hovered_files: Vec<HoveredFile>,
 
     /// Dragged files dropped into egui.
+    ///
+    /// Note: when using `eframe` on Windows you need to enable
+    /// drag-and-drop support using `epi::NativeOptions`.
     pub dropped_files: Vec<DroppedFile>,
 }
 
diff --git a/egui_demo_app/src/main.rs b/egui_demo_app/src/main.rs
index 806fbe0c..a0295142 100644
--- a/egui_demo_app/src/main.rs
+++ b/egui_demo_app/src/main.rs
@@ -9,6 +9,7 @@ fn main() {
     let options = eframe::NativeOptions {
         // Let's show off that we support transparent windows
         transparent: true,
+        drag_and_drop_support: true,
         ..Default::default()
     };
     eframe::run_native(Box::new(app), options);
diff --git a/epi/src/lib.rs b/epi/src/lib.rs
index 1a7d548a..e50bfb5f 100644
--- a/epi/src/lib.rs
+++ b/epi/src/lib.rs
@@ -180,8 +180,9 @@ pub struct NativeOptions {
     pub decorated: bool,
 
     /// On Windows: enable drag and drop support.
-    /// Default is `false` to avoid issues with crates such as cpal which
-    /// uses that use multi-threaded COM API <https://github.com/rust-windowing/winit/pull/1524>
+    /// Default is `false` to avoid issues with crates such as [`cpal`](https://github.com/RustAudio/cpal) which
+    /// will hang when combined with drag-and-drop.
+    /// See <https://github.com/rust-windowing/winit/issues/1255>.
     pub drag_and_drop_support: bool,
 
     /// The application icon, e.g. in the Windows task bar etc.