FileEngine: expose native file types on different platforms (#1258)

* Get native file

* Correct visibility

packages/web/src/file_engine.rs

@@ -1,3 +1,5 @@
+use std::any::Any;
+
 use dioxus_html::FileEngine;
 use futures_channel::oneshot;
 use js_sys::Uint8Array;
@@ -100,4 +102,25 @@ impl FileEngine for WebFileEngine {
             None
         }
     }
+
+    async fn get_native_file(&self, file: &str) -> Option<Box<dyn Any>> {
+        let file = self.find(file)?;
+        Some(Box::new(file))
+    }
+}
+
+/// Helper trait for WebFileEngine
+#[async_trait::async_trait(?Send)]
+pub trait WebFileEngineExt {
+    /// returns web_sys::File
+    async fn get_web_file(&self, file: &str) -> Option<web_sys::File>;
+}
+
+#[async_trait::async_trait(?Send)]
+impl WebFileEngineExt for std::sync::Arc<dyn FileEngine> {
+    async fn get_web_file(&self, file: &str) -> Option<web_sys::File> {
+        let native_file = self.get_native_file(file).await?;
+        let ret = native_file.downcast::<web_sys::File>().ok()?;
+        Some(*ret)
+    }
 }

packages/web/src/lib.rs

@@ -54,6 +54,7 @@
 //     - Do DOM work in the next requestAnimationFrame callback
 
 pub use crate::cfg::Config;
+pub use crate::file_engine::WebFileEngineExt;
 use dioxus_core::{Element, Scope, VirtualDom};
 use futures_util::{
     future::{select, Either},