How to response Drag and Drop action in Admin privilege?

[Mikachu2333]

As the title shows. I've tried ChangeWindowMessageFilter and ChangeWindowMessageFilterEx, but nothing happened. What should I do?

Should i use Win Message Loop?

main.rs

#![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]

use core::ffi::c_void;
use eframe::egui::{self};
use is_elevated::is_elevated;
use std::sync::atomic::{AtomicI32, Ordering};
use windows_sys::Win32::UI::WindowsAndMessaging::{
    ChangeWindowMessageFilter, MSGFLT_ADD, WM_COPYDATA, WM_DROPFILES,
};
use winit::raw_window_handle::{HasWindowHandle, RawWindowHandle, Win32WindowHandle};

static WINDOW_HANDLE: AtomicI32 = AtomicI32::new(0);

fn main() -> eframe::Result {
    let options = eframe::NativeOptions {
        viewport: egui::ViewportBuilder::default()
            .with_inner_size([350.0, 250.0])
            .with_drag_and_drop(true)
            .with_always_on_top(),
        centered: true,
        ..Default::default()
    };

    eframe::run_native(
        "Test",
        options,
        Box::new(|cc| {
            let RawWindowHandle::Win32(handle) = cc.window_handle().unwrap().as_raw() else {
                panic!("Unsupported platform");
            };
            println!("HANDLE: {:x}", handle.hwnd);
            WINDOW_HANDLE.store(handle_to_hwnd(handle) as i32, Ordering::SeqCst);

            if is_elevated() {
                unsafe {
                    ChangeWindowMessageFilter(WM_DROPFILES, MSGFLT_ADD);
                    ChangeWindowMessageFilter(WM_COPYDATA, MSGFLT_ADD);
                }
            };

            Ok(Box::<MyApp>::default())
        }),
    )
}

#[derive(Default)]
struct MyApp {
    text_string1: String,
}

impl eframe::App for MyApp {
    fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
        if !ctx.input(|i| i.raw.dropped_files.is_empty()) {
            ctx.input(|i| {
                for dropped_file in &i.raw.dropped_files {
                    if let Some(file_path) = &dropped_file.path {
                        let path_string = file_path.to_string_lossy().to_string();
                        self.text_string1 = path_string;
                    }
                }
            });
        }
        egui::CentralPanel::default().show(ctx, |ui| {
            ui.text_edit_singleline(&mut self.text_string1);
        });
    }
}

fn handle_to_hwnd(handle: Win32WindowHandle) -> windows_sys::Win32::Foundation::HWND {
    let hwnd_isize: isize = handle.hwnd.into();
    let hwnd = hwnd_isize as *mut c_void;

    hwnd as windows_sys::Win32::Foundation::HWND
}

cargo.toml

[package]
name = "test_proj"
version = "0.1.0"
edition = "2021"

[build-dependencies]
winres = "0.1.12"

[dependencies]
eframe = "0.31.1"
windows-sys = { version = "0.59.0", features = ["Win32_UI_WindowsAndMessaging"] }
winit = "0.30.9"
is_elevated = "0.1.2"

build.rs

extern crate winres;
use winres::VersionInfo;

fn main() {
    if std::env::var("CARGO_CFG_TARGET_OS").unwrap() != "windows" {
        return;
    }

    let mut res = winres::WindowsResource::new();

    let mut version = 0;
    version |= 1 << 48;
    version |= 0 << 32;
    version |= 0 << 16;
    version |= 0;

    res.set_version_info(VersionInfo::FILEVERSION, version)
        .set_version_info(VersionInfo::PRODUCTVERSION, version);

    res.set_manifest_file("manifest.xml");

    if let Err(e) = res.compile() {
        eprintln!("{}", e);
        std::process::exit(1);
    }
}

mainfest.xml

<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
  <compatibility xmlns="urn:schemas-microsoft-com:compatibility.v1">
    <application>
      <supportedOS Id="{35138b9a-5d96-4fbd-8e2d-a2440225f93a}" />
    </application>
  </compatibility>
  <trustInfo xmlns="urn:schemas-microsoft-com:asm.v3">
    <security>
      <requestedPrivileges>
        <requestedExecutionLevel
          level="requireAdministrator"
          uiAccess="false" />
      </requestedPrivileges>
    </security>
  </trustInfo>
</assembly>

Related link

https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-changewindowmessagefilter
https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-changewindowmessagefilterex
https://en.wikipedia.org/wiki/User_Interface_Privilege_Isolation
https://github.com/Chaoses-Ib/Windows/blob/main/Kernel/Security/UIPI.md
https://github.com/HerMajestyDrMona/Windows11DragAndDropToTaskbarFix/blob/main/Windows11DragAndDropToTaskbarFix/Windows11DragAndDropToTaskbarFix.cpp

[Mikachu2333]

GPT told me that with uiaccess=true option, it could work but I failed...