[v2] runtime.SomeDialog causes application to crash on linux

[lambdajack]

Description

Calling runtime.OpenDirectorDialog (or any of the dialog options described in the docs here) causes the application to crash on linux.

Tested on fresh ubuntu and fedora updated vms (as well as bare metal ubuntu).

The exact same application works as expected in windows.

To Reproduce

1. wails init -n menutest -t react-ts
2. Set up a menu on the app like this:

package main

import (
	"context"
	"embed"
	"fmt"

	"github.com/wailsapp/wails/v2"
	"github.com/wailsapp/wails/v2/pkg/menu"
	"github.com/wailsapp/wails/v2/pkg/options"
	"github.com/wailsapp/wails/v2/pkg/runtime"
)

//go:embed frontend/dist
var assets embed.FS

type App struct {
	ctx context.Context
}
func NewApp() *App {
	return &App{}
}
func (a *App) startup(ctx context.Context) {
	a.ctx = ctx
}
func (a *App) setMenu() *menu.Menu {
	return menu.NewMenuFromItems(
		menu.SubMenu("File", menu.NewMenuFromItems(
			// ---------------------------------------------------------------------
			menu.Text("Dialog 1", nil, func(_ *menu.CallbackData) {
				fmt.Println("Dialog 1 callback fires")
				runtime.OpenMultipleFilesDialog(a.ctx, runtime.OpenDialogOptions{
					Title:         "Application crash on linux",
				})
			}),
			// ---------------------------------------------------------------------
			menu.Text("Dialog 2", nil, func(_ *menu.CallbackData) {
				fmt.Println("Dialog 2 callback fires")
				runtime.OpenDirectoryDialog(a.ctx, runtime.OpenDialogOptions{
					Title:         "Application crash on linux",
				})
			}),
			// ---------------------------------------------------------------------
			menu.Text("Quit", nil, func(_ *menu.CallbackData) {
				fmt.Println("Quit callback fires (works on all os)")
				runtime.Quit(a.ctx)
			}),
		)))
}

func main() {
	app := NewApp()

	err := wails.Run(&options.App{
		Title:     "Menu Does not work on linux",
		Width:     1024,
		Height:    768,
		Assets:    assets,
		Menu: app.setMenu(), // the dialog items work on windows, not linux (fedora & ubuntu tested)
		OnStartup: app.startup,
		Bind: []interface{}{
			app,
		},
	})

	if err != nil {
		println("Error:", err)
	}
}

3. Remove the default Greet function dependency from the frontend if you copied/pasted the above.
4. wails dev or wails build
5. The application will run as expected - however when you try to select one of the file/dialog options, the window will crash and become totally unresponsive. (try typing in the box or clicking the buttons).
6. Get the same project over to a windows vm and run it. It will work as expected.

Expected behaviour

The dialog options should open on linux the same way they do on windows.

Screenshots

Fig1 - application crash on ubuntu

Fig2 - application crash on fedora

Fig3 - working on windows

Attempted Fixes

I have tried implementing the menu without using the menu.NewMenuFromItems helper function, however the problem remains.

I have also tried on master.

System Details

1. UBUNTU:

Wails CLI v2.0.0-beta.36


Scanning system - Please wait (this may take a long time)...Done.

System
------
OS:             Ubuntu
Version:        22.04
ID:             ubuntu
Go Version:     go1.18.1
Platform:       linux
Architecture:   amd64

Wails
------
Version:                v2.0.0-beta.36
Revision:               35b1dfdd2a2165b29ef5c2728d3adbd57a062710
Modified:               false
Package Manager:        apt

Dependency      Package Name            Status          Version
----------      ------------            ------          -------
*docker         docker.io               Installed       20.10.14
gcc             build-essential         Installed       12.9ubuntu3
libgtk-3        libgtk-3-dev            Installed       3.24.33-1ubuntu1
libwebkit       libwebkit2gtk-4.0-dev   Installed       2.36.0-2ubuntu1
npm             npm                     Installed       8.9.0
*nsis           nsis                    Installed       v3.08-2
pkg-config      pkg-config              Installed       0.29.2

* - Optional Dependency

Diagnosis
---------
Your system is ready for Wails development!


If Wails is useful to you or your company, please consider sponsoring the project:
https://github.com/sponsors/leaanthony

2: FEDORA:

Wails CLI v2.0.0-beta.36


Scanning system - Please wait (this may take a long time)...Done.

System
------
OS:             Ubuntu
Version:        22.04
ID:             ubuntu
Go Version:     go1.18.1
Platform:       linux
Architecture:   amd64

Wails
------
Version:                v2.0.0-beta.36
Revision:               35b1dfdd2a2165b29ef5c2728d3adbd57a062710
Modified:               false
Package Manager:        apt

Dependency      Package Name            Status          Version
----------      ------------            ------          -------
*docker         docker.io               Installed       20.10.14
gcc             build-essential         Installed       12.9ubuntu3
libgtk-3        libgtk-3-dev            Installed       3.24.33-1ubuntu1
libwebkit       libwebkit2gtk-4.0-dev   Installed       2.36.0-2ubuntu1
npm             npm                     Installed       8.9.0
*nsis           nsis                    Installed       v3.08-2
pkg-config      pkg-config              Installed       0.29.2

* - Optional Dependency

Diagnosis
---------
Your system is ready for Wails development!


If Wails is useful to you or your company, please consider sponsoring the project:
https://github.com/sponsors/leaanthony

3. WINDOWS:

Wails CLI v2.0.0-beta.36


Scanning system - Please wait (this may take a long time)...Done.

System
------
OS:             Windows 10 Enterprise Evaluation
Version:        2009 (Build: 22000)
ID:             21H2
Go Version:     go1.18.1
Platform:       windows
Architecture:   amd64

Wails
------
Version:        v2.0.0-beta.36

Dependency      Package Name    Status          Version
----------      ------------    ------          -------
WebView2        N/A             Installed       101.0.1210.47
npm             N/A             Installed       8.5.5
*upx            N/A             Available
*nsis           N/A             Available

* - Optional Dependency

Diagnosis
---------
Your system is ready for Wails development!
Optional package(s) installation details:
  - upx : Available at https://upx.github.io/
  - nsis : Available at https://nsis.sourceforge.io/Download



If Wails is useful to you or your company, please consider sponsoring the project:
https://github.com/sponsors/leaanthony

### Additional context

_No response_

[leaanthony]

Thanks for the very detailed report Jack 🙏 It's very likely to be a threading issue, but interesting that @ianmjones hasn't seen this.

[stffabi]

Would be interesting to see if PR #1392 would fix this issue.
@lambdajack Would it be possible for you to give that PR a try? That would be really awesome

[lambdajack]

Happy to help @leaanthony - you are both onto something with the threading.

@stffabi interestingly your PR #1392 has some positive effect on the problem, but does not resolve the issue completely.

Using #1392 the dialog windows themselves open as expected (excellent!) (see screenshots below). I am able to navigate around the file system and highlight files/folders etc...

The problems resume however, when trying to either 'Cancel' the dialog, or 'Open' the selected files/folders. When trying to interact with the Dialog's native buttons, the application crashes again. This appears to be the case with each of the runtime.Dialog functions.

Using the same PR, the application still functions as expected and dialog windows remain responsive on windows.

It appears GTK may be somewhat involved, as I get the following errors in the terminal, only when clicking a dialog native button (like 'Cancel' or 'OK'):

Ubuntu:

Dialog 2 callback fires

(boilerplate-dev-linux-amd64:1246185): Gtk-CRITICAL **: 02:48:18.525: gtk_window_set_transient_for: assertion 'parent == NULL || GTK_IS_WINDOW (parent)' failed

Fedora:

(process:27238): GLib-CRITICAL **: 02:53:59.671: Failed to set scheduler settings: Operation not permitted
Dialog 2 callback fires

(boilerplate-dev-linux-amd64:27210): Gtk-CRITICAL **: 02:54:01.700: gtk_window_set_transient_for: assertion 'parent == NULL || GTK_IS_WINDOW (parent)' failed

Thanks for the quick response on this one guys - I'll have a look into it also, but I must be honest, GTK is not my forte! Though I suppose it might just be that GTK is looking for something on the wrong thread?

Let me know if there's anything more I can do!

[stffabi]

@lambdajack Thanks for testing #1392

I was able to reproduce the problem on my latest Fedora on arm64. It seems like it get's triggered when the dialogs are opened through the menu callback. From the message "is not responding" I suspected that the main thread is somehow blocked and this stopped GTK from processing messages for the native part. Adding a go before opening the dialogs got them working.

At line 28 we are waiting for the results of the dialog and that's going to block the message loop since OpenFileDialog is called from the menu callback which is on the main thread:

wails/v2/internal/frontend/desktop/linux/dialog.go

Lines 26 to 33 in 35b1dfd

	func (f *Frontend) OpenFileDialog(dialogOptions frontend.OpenDialogOptions) (result string, err error) {
	f.mainWindow.OpenFileDialog(dialogOptions, 0, GTK_FILE_CHOOSER_ACTION_OPEN)
	results := <-openFileResults
	if len(results) == 1 {
	return results[0], nil
	}
	return "", nil
	}

I think we should call the menu click callbacks on a new goroutine and that should fix the issue. @leaanthony do you see a problem with that?
I've created PR #1403 which executes the callbacks in another goroutine, this is without the changes from #1392, nevertheless it should fix the issue. @lambdajack could you please give it another try?

[lambdajack]

Great stuff @stffabi! #1403 works as expected on ubuntu, fedora and windows for me. I wasn't able to cause a crash on that PR.

I am still seeing console errors on linux when pressing the menu button to open the dialog, but they don't appear to be fatal as the application remains responsive and the function return values are as expected, even after many dialog open/close ops:

Windows shows no console errors.

Ubuntu:

Dialog 1 callback fires

(boilerplate-dev-linux-amd64:1380611): Gtk-CRITICAL **: 08:27:01.937: gtk_window_set_transient_for: assertion 'parent == NULL || GTK_IS_WINDOW (parent)' failed

Fedora:

Dialog 1 callback fires

(boilerplate-dev-linux-amd64:31086): Gtk-CRITICAL **: 08:28:51.894: gtk_window_set_transient_for: assertion 'parent == NULL || GTK_IS_WINDOW (parent)' failed

[stffabi]

@lambdajack Awesome thanks so much for testing it and your feedback.

Yeah, I've just pushed a new commit to the PR, which fixes those assertion messages.