Getting FileChooserNative.New to display

[PlatinumLucario]

I have been attempting to get FileChooserNative.New to display a folder selection dialog, but oddly enough, the variable I specified ends up being skipped, without any errors. It works fine when I do something similar in C though.

This was my earlier attempt:

private void OpenDSE(object? sender, EventArgs? e)
        {
            var d = FileChooserNative.New(
                Strings.MenuOpenDSE,
                this,
                FileChooserAction.SelectFolder, "Select Folder", "Cancel");

            d.SetModal(true);

            d.OnResponse += (sender, e) =>
            {
                if (e.ResponseId != (int)ResponseType.Accept)
                {
                    //d.Unref();
                    return;
                }
            };
            d.Show();
        }

Here's my latest attempt:

private void OpenDSE(object? sender, EventArgs? e)
        {
            var d = FileChooserNative.New(
                Strings.MenuOpenDSE,
                this,
                FileChooserAction.SelectFolder, "Select Folder", "Cancel");

            d.SetModal(true);

            d.OnResponse += (sender, e) =>
            {
                if (e.ResponseId == (int)ResponseType.Accept)
                {
                    var path = d.GetCurrentFolder()!.GetPath() ?? "";
                    d.GetData(path);
                }
                else
                {
                    //d.Unref();
                    return;
                }
            };
            d.Show();
        }

I have checked other projects to be absolutely sure that I'm not missing any functions, but everything seems identical.

Is there any extra files required in the ./share directory other than glib-2.0? I have copied gtk-4.0 and gtksourceview-5 folders from the mingw64/share directory into the project's ./share directory, but it didn't make any difference.

[hol430]

Which version of gtk are you using? And what exactly is going wrong? There is a bug in recent versions (>=4.10) which also doesn't show up for me in an equivalent C program.

Denaro works around this by manually wrapping and using FileDialog on 4.10+ versions.

[fsobolev]

The version of Gir.Core I'm using is 0.3.0, and from what I've noticed with Denaro, is that it uses 0.2.0 instead,

Err, no, we're always on the latest version, currently 0.3.0: csproj, flatpak sources

And... nothing?

You placed SelectFolder inside the callback, it should be after }; (like here)

[PlatinumLucario]

You placed SelectFolder inside the callback, it should be after }; (like here)

Ah awesome!

SelectFolder(d, Handle, IntPtr.Zero, _folderSelectCallback, IntPtr.Zero);

Glad it was noticed, though even after placing it outside of the callback, it was still skipped though, so this is definitely the bug in Gtk 4.10, like @badcel mentioned. So even FileDialog is affected, it seems.

[PlatinumLucario]

I tested out GtkFileChooserNative and GtkFileDialog on Arch Linux, it seems to have the exact same issue I encountered while building under Windows. So I can definitely rule out an OS issue, regarding the FileDialog and FileChooserNative dialogs not appearing and being skipped.

I did try using the same method that Denaro uses, but I don't think I implemented it properly. Either that, or it's because I'm using VSCode and vsdbg to compile the application.

So I thought it was due to some other code in the application I'm working on that was causing it to skip the FileDialog from popping up. So to make sure it was, I attempted to make another project based on one of the samples, and modify it to what Denaro implemented it as, as shown here:

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Runtime.InteropServices;
using System.Threading.Tasks;
using Adw;

namespace GirCoreSampleTest;

public partial class Program
{

    private delegate void GAsyncReadyCallback(nint source, nint res, nint user_data);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial string g_file_get_path(nint file);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial nint gtk_file_dialog_new();

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial void gtk_file_dialog_set_title(nint dialog, string title);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial void gtk_file_dialog_set_filters(nint dialog, nint filters);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial void gtk_file_dialog_open(nint dialog, nint parent, nint cancellable, GAsyncReadyCallback callback, nint user_data);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial nint gtk_file_dialog_open_finish(nint dialog, nint result, nint error);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial void gtk_file_dialog_save(nint dialog, nint parent, nint cancellable, GAsyncReadyCallback callback, nint user_data);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial nint gtk_file_dialog_save_finish(nint dialog, nint result, nint error);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial nint gtk_file_launcher_new(nint file);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial void gtk_file_launcher_launch(nint fileLauncher, nint parent, nint cancellable, GAsyncReadyCallback callback, nint data);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial nint gtk_uri_launcher_new(string uri);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial void gtk_uri_launcher_launch(nint uriLauncher, nint parent, nint cancellable, GAsyncReadyCallback callback, nint data);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial nint g_file_new_for_path(string path);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial nint g_file_icon_new(nint gfile);

    [LibraryImport("libadwaita-1.so.0", StringMarshalling = StringMarshalling.Utf8)]
    private static partial void g_notification_set_icon(nint notification, nint icon);

    private readonly Adw.Application _application;

    [Gtk.Connect] private Gtk.Popover? _accountPopover;
    [Gtk.Connect] private Gtk.Button? _openAccountButton;

    private Gio.SimpleAction? _actOpenAccount;
    
    private GAsyncReadyCallback? _openCallback { get; set; }

    [STAThread]
    public static int Main(string[] args) => new Program().Run(args);
    public Program()
    {
        _application = Adw.Application.New("org.gir.core", Gio.ApplicationFlags.NonUnique);
        _application.OnActivate += (sender, args) =>
        {
            _openAccountButton = new Gtk.Button();
            var maxBtnWidth = Math.Max(_openAccountButton.GetAllocatedWidth(), _openAccountButton.GetAllocatedWidth());
            _openAccountButton.SetSizeRequest(maxBtnWidth, -1);
            _openAccountButton.SetLabel("Open File");
            var window = Gtk.ApplicationWindow.New((Adw.Application) sender);
            window.Title = "Window";
            window.SetDefaultSize(300, 300);
            window.SetChild(_openAccountButton);

            _actOpenAccount = Gio.SimpleAction.New("openAccount", null);
            _actOpenAccount.OnActivate += OnOpenAccount;
            _application.AddAction(_actOpenAccount);
            _application.SetAccelsForAction("win.openAccount", new string[] { "<Ctrl>O" });

            window.Show();
    
            void OnOpenAccount(Gio.SimpleAction sender, EventArgs e)
            {

                //_accountPopover.Popdown();
                var filter = Gtk.FileFilter.New();
                filter.SetName($"Wave Data (*.swd)");
                filter.AddPattern("*.swd");
                filter.AddPattern("*.SWD");
                var openFileDialog = gtk_file_dialog_new();
                gtk_file_dialog_set_title(openFileDialog, "Open Wave Data");
                var filters = Gio.ListStore.New(Gtk.FileFilter.GetGType());
                filters.Append(filter);
                gtk_file_dialog_set_filters(openFileDialog, filters.Handle);
                _openCallback = (source, res, data) =>
                {
                    var fileHandle = gtk_file_dialog_open_finish(openFileDialog, res, IntPtr.Zero);
                    if (fileHandle != IntPtr.Zero)
                    {
                        var path = g_file_get_path(fileHandle);
                        //await _controller.AddAccountAsync(path);
                    }
                };
                gtk_file_dialog_open(openFileDialog, _application.Handle, IntPtr.Zero, _openCallback, IntPtr.Zero);
            }
        };
        _application.Run();
        return;
    }

        public int Run(string[] args)
        {
            try
            {
                var argv = new string[args.Length + 1];
                argv[0] = "org.gir.core";
                args.CopyTo(argv, 1);
                return _application.Run(args.Length + 1, argv);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
                Console.WriteLine($"\n\n{ex.StackTrace}");
                return -1;
            }
        }
}

But nope, it still had the same issue. The FileDialog function would always get skipped when activated.
Now the question to @fsobolev is this: Does the workaround this bug require using the blueprints-compiler? And is there anything in this code that's missing or prevents GtkFileDialog from working?

[fsobolev]

@PlatinumLucario There are 2 problems with your example:

1. You added the action to application, not to the window, so the action name is app.openAccount, not win.openAccount. Either change the action name, or add it to the window instead of application. This will make keyboard shortcut work.
2. Your button doesn't do anything. If you want it to activate the action, add _openAccountButton.SetActionName("app.openAccount"); (or win.openAccount if you connect it to the window).

I'm currently on Arch, and with fixes above your example runs successfully.

[PlatinumLucario]

@PlatinumLucario There are 2 problems with your example:

1. You added the action to application, not to the window, so the action name is `app.openAccount`, not `win.openAccount`. Either change the action name, or add it to the window instead of application. This will make keyboard shortcut work.

2. Your button doesn't do anything. If you want it to activate the action, add `_openAccountButton.SetActionName("app.openAccount");` (or `win.openAccount` if you connect it to the window).

I'm currently on Arch, and with fixes above your example runs successfully.

I think your answer pretty much solves the problem that I have with implementing GTK4 as VG Music Studio's replacement UI. Which definitely tells me that somewhere in there, I will need to fix the action name string in there. So app for applying it to the application, and win for applying it to the window itself.

Thank you so much!

[PlatinumLucario]

Also, I found the exact problem in VG Music Studio. It turns out that the FileDialog doesn't display until it has reached the end of the entire code. Is this intentional in GTK4? Or is this a separate bug within GTK4? @badcel

The only way I got it to work, is to place a return before it reaches DSEConfig config = DSEEngine.DSEInstance!.Config;, otherwise it will attempt to read through the rest of the application code before it shows a FileDialog

[cameronwhite]

Showing the dialog is not a blocking call in GTK4 (https://docs.gtk.org/gtk4/migrating-3to4.html#stop-using-blocking-dialog-functions) so you do need to be careful about what you call after showing the file dialog - subsequent code might belong in the OnResponse callback instead
Depending on the details of what the dialog does, perhaps it needs control to return to the GTK event loop before it ends up being displayed which would explain the behaviour you're seeing

[PlatinumLucario]

After reading about GTK4 removing the blocking APIs for dialogs, it makes sense. Prior to GTK4, it used blocking APIs, which explains why it operated differently.

If I remember correctly, I do have a callback in there somewhere, ah yeah, here it is:

if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
                {
                    var d = linux_gtk_file_dialog_new();
                    LinuxSetTitle(d, Strings.MenuOpenDSE);

                    _folderSelectCallback = (source, res, data) =>
                    {
                        var folderHandle = LinuxSelectFolderFinish(d, res, IntPtr.Zero);
                        if (folderHandle != IntPtr.Zero)
                        {
                            var path = LinuxGetPath(folderHandle);
                            DisposeEngine();
                            try
                            {
                                _ = new DSEEngine(path);
                            }
                            catch (Exception ex)
                            {
                                FlexibleMessageBox.Show(ex, Strings.ErrorOpenDSE);
                                return;
                            }
                            DSEConfig config = DSEEngine.DSEInstance!.Config;
                            FinishLoading(config.BGMFiles.Length);
                            _sequenceNumberSpinButton.Visible = false;
                            _sequenceNumberSpinButton.Hide();
                            _exportDLSWidget.Visible = false;
                            _exportMIDIWidget.Visible = false;
                            _exportSF2Widget.Visible = false;
                        }
                    };
                    LinuxSelectFolder(d, Handle, IntPtr.Zero, _folderSelectCallback, IntPtr.Zero);
                    return;
                }

I also modified it earlier to place the DSEConfig config = DSEEngine.DSEInstance!.Config; and other functions that come after it, into the callback so that it would only reach it once it has a folder path selected.