Compatibility with bevy_egui.

[Oglo12]

I tried using this crate with bevy_egui, but it doesn't like it. The code is just incompatible. Won't even compile. It is because you require the standard Egui context.

[Barugon]

It works.

[dependencies]
bevy = "0.14"
bevy_egui = "0.28"
egui_file = "0.18"

use bevy::prelude::*;
use bevy_egui::{EguiContexts, EguiPlugin};
use egui_file::FileDialog;

fn main() {
  let mut dialog = FileDialog::open_file(None);
  dialog.open();

  let ui_example_system = move |mut contexts: EguiContexts| {
    dialog.show(contexts.ctx_mut());
  };

  App::new()
    .add_plugins(DefaultPlugins)
    .add_plugins(EguiPlugin)
    .add_systems(Update, ui_example_system)
    .run();
}

[coderPaddyS]

With the introduction of Vfs, so version 0.21, a closure capturing the FileDialog cannot be turned into a egui system anymore.
The following code does not compile:

fn main() {

    let file_dialog = FileDialog { dialog: None };
    App::new()
        .add_plugins(DefaultPlugins)
        .add_plugins(EguiPlugin)
        .add_systems(Startup, setup)
        .add_systems(Update, move || { file_dialog })
        .run();
}

The according compiler error:

error[E0277]: `{closure@src/main.rs:160:30: 160:37}` does not describe a valid system configuration
   --> src/main.rs:160:30
    |
160 |         .add_systems(Update, move || { file_dialog })
    |          -----------         ^^^^^^^^^^^^^^^^^^^^^^^ invalid system configuration
    |          |
    |          required by a bound introduced by this call
    |
    = help: the trait `bevy::prelude::IntoSystem<(), (), _>` is not implemented for closure `{closure@src/main.rs:160:30: 160:37}`
    = help: the following other types implement trait `bevy::prelude::IntoSystem<In, Out, Marker>`:
              `IntoAdapterSystem<Func, S>` implements `bevy::prelude::IntoSystem<<Func as Adapt<<S as bevy::prelude::IntoSystem<I, O, M>>::System>>::In, <Func as Adapt<<S as bevy::prelude::IntoSystem<I, O, M>>::System>>::Out, (IsAdapterSystemMarker, I, O, M)>`
              `IntoPipeSystem<A, B>` implements `bevy::prelude::IntoSystem<IA, OB, (IsPipeSystemMarker, OA, IB, MA, MB)>`
    = note: required for `{closure@src/main.rs:160:30: 160:37}` to implement `IntoSystemConfigs<_>`
note: required by a bound in `App::add_systems`
   --> $HOME/.cargo/registry/src/index.crates.io-6f17d22bba15001f/bevy_app-0.15.1/src/app.rs:288:23
    |
285 |     pub fn add_systems<M>(
    |            ----------- required by a bound in this associated function
...
288 |         systems: impl IntoSystemConfigs<M>,
    |                       ^^^^^^^^^^^^^^^^^^^^ required by this bound in `App::add_systems`

error[E0277]: `impl FnMut(Res<'a, ButtonInput<KeyCode>>, EguiContexts<'b, 'c>, ResMut<'d, Assets<Mesh>>, Single<'e, (&mut Mesh3d, ...)>)` does not describe a valid system configuration
   --> src/main.rs:161:31
    |
161 |         .add_systems(Update,  FileDialog::openMesh())
    |          -----------          ^^^^^^^^^^^^^^^^^^^^^^ invalid system configuration
    |          |
    |          required by a bound introduced by this call
    |
    = note: the full name for the type has been written to '/home/patrick/Coding/BA/target/debug/deps/ba-424857715c0771a0.long-type-2022787241295028123.txt'
    = note: consider using `--verbose` to print the full type name to the console
    = help: the trait `bevy::prelude::IntoSystem<(), (), _>` is not implemented for `impl FnMut(Res<'a, ButtonInput<KeyCode>>, EguiContexts<'b, 'c>, ResMut<'d, Assets<Mesh>>, Single<'e, (&mut Mesh3d, ...)>)`
    = help: the following other types implement trait `bevy::prelude::IntoSystem<In, Out, Marker>`:
              `IntoAdapterSystem<Func, S>` implements `bevy::prelude::IntoSystem<<Func as Adapt<<S as bevy::prelude::IntoSystem<I, O, M>>::System>>::In, <Func as Adapt<<S as bevy::prelude::IntoSystem<I, O, M>>::System>>::Out, (IsAdapterSystemMarker, I, O, M)>`
              `IntoPipeSystem<A, B>` implements `bevy::prelude::IntoSystem<IA, OB, (IsPipeSystemMarker, OA, IB, MA, MB)>`
    = note: required for `impl FnMut(Res<'a, ButtonInput<KeyCode>>, EguiContexts<'b, 'c>, ResMut<'d, Assets<Mesh>>, Single<'e, (&mut Mesh3d, ...)>)` to implement `IntoSystemConfigs<_>`
note: required by a bound in `App::add_systems`
   --> $HOME/.cargo/registry/src/index.crates.io-6f17d22bba15001f/bevy_app-0.15.1/src/app.rs:288:23
    |
285 |     pub fn add_systems<M>(
    |            ----------- required by a bound in this associated function
...
288 |         systems: impl IntoSystemConfigs<M>,
    |                       ^^^^^^^^^^^^^^^^^^^^ required by this bound in `App::add_systems`
    = note: the full name for the type has been written to '/home/patrick/Coding/BA/target/debug/deps/ba-424857715c0771a0.long-type-2022787241295028123.txt'
    = note: consider using `--verbose` to print the full type name to the console

Changing back to version 0.20 resolves this issue. I'm using bevy_egui version 0.32.0 and bevy version 0.15.1, so the latest.

[Barugon]

Can you give the main branch a try and let me know if it fixes this for you?

[coderPaddyS]

With the current main I get the following error:

143 |         .add_systems(Update, move || { file_dialog })
    |          -----------         ^^^^^^^^^^^^^^^^^^^^^^^ invalid system configuration
    |          |
    |          required by a bound introduced by this call
    |
    = help: the trait `bevy::prelude::IntoSystem<(), (), _>` is not implemented for closure `{closure@src/main.rs:143:30: 143:37}`
    = help: the following other types implement trait `bevy::prelude::IntoSystem<In, Out, Marker>`:
              `IntoAdapterSystem<Func, S>` implements `bevy::prelude::IntoSystem<<Func as Adapt<<S as bevy::prelude::IntoSystem<I, O, M>>::System>>::In, <Func as Adapt<<S as bevy::prelude::IntoSystem<I, O, M>>::System>>::Out, (IsAdapterSystemMarker, I, O, M)>`
              `IntoPipeSystem<A, B>` implements `bevy::prelude::IntoSystem<IA, OB, (IsPipeSystemMarker, OA, IB, MA, MB)>`
    = note: required for `{closure@src/main.rs:143:30: 143:37}` to implement `IntoSystemConfigs<_>`
note: required by a bound in `App::add_systems`

So it seems to be the same issue.

[Barugon]

Do you have a minimum reproducible example? The code I posted above works with the current main.