Gtk# 应用程序未正确呈现 TreeView

Question

I am trying to develop a gtk application on mac using gtk#. I created a tree view just like in the tutorial but the arrows are not rendering properly as seem below, there are no arrows. I can click to open and close but the actual arrows aren't working.

I copy pasted the code from the tutorial and It did the same thing, but here is my code anywhere. I have also verified view.ShowExpanders is set to true

        Application.Init();

        Window window = new Window("Editor Window");

        window.SetPosition(WindowPosition.Center);
        window.HeightRequest = 800;
        window.WidthRequest = 1200;

        TreeView view = new TreeView();

        view.WidthRequest = 500;

        TreeViewColumn column = new TreeViewColumn();
        column.Title = "Heirarchy";

        CellRendererText cell = new CellRendererText();

        column.PackStart(cell, true);

        view.AppendColumn(column);

        column.AddAttribute(cell, "text", 0);

        TreeStore store = new TreeStore(typeof(string));

        TreeIter i = store.AppendValues("Project");
        i = store.AppendValues(i,"Room1");
        i = store.AppendValues(i, "Item");
        store.AppendValues(i, "Attribute");
        store.AppendValues(i, "Attribute");
        store.AppendValues(i, "Attribute");


        view.ShowExpanders = true;

        view.Model = store;
        view.ShowExpanders = true;

        window.Add(view);

        window.DeleteEvent += ExitWindow;

        window.ShowAll();

        Application.Run();

Is there some sort of image asset that doesn't exist on my computer? How would I install that on mac? Thank you for any help you can provide.

Answer 1

As a comment suggested, using brew install adwaita-icon-theme fixed the problem