Clipboard read_value_finish

[gummybears]

I am working on a Gtk4 Clipboard example and need to call the method clipboard.read_value_finish

  @[GObject::Virtual]
  def activate
    ui  = get_ui()
    builder     = Gtk::Builder.new_from_string(ui, ui.bytesize.to_i64)
    window      = Gtk::Window.cast(builder["window"])
    text_entry  = Gtk::Entry.cast(builder["source_text"])
    text_entry.changed_signal.connect do
      text_entry_changed(text_entry)
    end

    source_file    = Gtk::Button.cast(builder["source_file"])
    copy_button  = Gtk::Button.cast(builder["copy_button"])
    paste_button = Gtk::Button.cast(builder["paste_button"])
    combobox     = Gtk::DropDown.cast(builder["source_chooser"])
    source_stack = Gtk::Stack.cast(builder["source_stack"])
    dest_stack     = Gtk::Stack.cast(builder["dest_stack"])

    source_clipboard   = source_stack.clipboard
    visible_child_name = ""

    copy_button.clicked_signal.connect do
      visible_child      = source_stack.visible_child
      visible_child_name = source_stack.visible_child_name
      case visible_child_name
        when "Text"

          text = visible_child.as(Gtk::Editable).text
          source_clipboard.set(text)
        when "Color"
        when "Image"
        when "File"
      end
    end

    paste_button.clicked_signal.connect do
      dest_clipboard = dest_stack.clipboard
      case visible_child_name
        when "Text"
          result = Gio::AsyncResult.new # ?????
          value  = source_clipboard.read_value_finish(result)
          if value
            dest_stack.set_visible_child_name = "Text"
            child = dest_stack.visible_child
            child.as(Gtk::Label).text = value
          end
      end
    end

    window.application = self
    window.present
  end

Problem I have is that the argument result has to be of type Gio::AsyncResult which is a module

Platform
Linux 21
Crystal 1.9.2 [1908c816f] (2023-07-19)
libgtk-4-1

[hugopl]

for each module there's a Abstract<modulename> class, e.g. Gio::AbstractAsyncResult, but they exist to be used as return value for GTK functions that returns interfaces (i.e. Crystal modules).

Anyway, I didn't work to have these GTK async APIs "crystalized" yet because when I needed them I just used the non-async versions, that depending on the use case may not affect the application.

[gummybears]

I found Gio::SimpleAsyncResult, see what happens.

If you are interested, the GTK4 demo repo I am working on is located at https://github.com/gummybears/gtk4_with_crystal

PS I am using version 0.15 of your shard.

[hugopl]

I think will be useful to link this tutorial on this shard README and on gi-crystal README as well.

[gummybears]

The repo https://github.com/gummybears/gtk4_with_crystal is public, work in progress so caveat emptor but you are more than welcome to include it in your README.

[hugopl]

The PR above add support for _async functions, however a lot of _finish functions uses out parameters and out parameters still not fully implemented in GICrystal... I think now I must deserve some attention to they... anyway, monkey patch a function with out parameters is much easier than monkey patch a function that receives a callback, so I believe this patch will make things easier...

As usual I'll test it with Tijolo for few days before merging it...