Recursive Menu System

Question

I'm trying to code up a recursive menu class, navigatable with the arrow keys, which is almost complete, it's just that, it appears to have minor problems in situations, after going up/down for a bit (the menu wraps) it gets unstable and weirdly starts going to sub items even when that group is closed.

Here's my input functions:

    {
        if (Keyboard.Pressed(Keys.Up))
        {
            if (Index >= 0)
            {
                if (!GoUp(Groups[Index]))
                {
                    Index--; if (Index == -1) Index = (Groups.Count - 1);
                    if (Groups[Index].Open) Groups[Index].Index = ((Groups[Index].Groups.Count + Groups[Index].Items.Count) - 1);
                }
            }
        }
        if (Keyboard.Pressed(Keys.Down))
        {
            if (Index >= 0)
            {
                if (!GoDown(Groups[Index])) Index++;
                if (Index >= Groups.Count) Index = 0;
            }
        }
    }
    internal bool GoUp(Group group)
    {
        if (!group.Open) return false;
        if ((group.Index >= 0) && (group.Index < group.Groups.Count) && group.Groups[group.Index].Open) if (GoUp(group.Groups[group.Index])) return true;
        group.Index--;
        if (group.Index == -1) return true;
        if ((group.Index >= 0) && (group.Index < group.Groups.Count) && group.Groups[group.Index].Open) group.Groups[group.Index].Index = ((group.Groups[group.Index].Groups.Count + group.Groups[group.Index].Items.Count) - 1);
        return (group.Index >= 0);
    }
    internal bool GoDown(Group group)
    {
        if (!group.Open) return false;
        if ((group.Index >= 0) && (group.Index < group.Groups.Count) && group.Groups[group.Index].Open) if (GoDown(group.Groups[group.Index])) return true;
        group.Index++;
        if (group.Index >= (group.Groups.Count + group.Items.Count)) { group.Index = -1; return false; }
        if ((group.Index >= 0) && (group.Index < group.Groups.Count)) group.Groups[group.Index].Index = -1;
        return true;
    }

It renders the menu fine, but for your sake, here's my drawing code:

    public void Draw(Batch batch, Vector2 position, SpriteFont font, int width)
    {
        VisibleItems = Groups.Count;
        for (var i = 0; i < Groups.Count; i++) DrawGroup(Groups[i], null, batch, ref position, font);
    }
    internal void DrawGroup(Group group, Group parent, Batch batch, ref Vector2 position, SpriteFont font)
    {
        const float textScale = .15f;
        batch.DrawString(group.Name, font, position, (((((parent == null) && (group == Groups[Index])) || ((parent != null) &&
            (parent.Index >= 0) && (parent.Groups.Count > parent.Index) && (group == parent.Groups[parent.Index]))) && (group.Index == -1)) ? GroupSelectedColor : GroupColor), new Vector2(textScale));
        position.Y += (font.MeasureString(group.Name).Y * textScale);
        if (group.Open)
        {
            var x1 = position.X;
            if (group.Groups.Count > 0)
            {
                position.X += 10;
                var x2 = position.X;
                for (var i = 0; i < group.Groups.Count; i++)
                {
                    DrawGroup(group.Groups[i], group, batch, ref position, font);
                    position.X = x2;
                }
                position.X -= 10;
            }
            if (group.Items.Count > 0)
            {
                position.X += 10;
                for (var i = 0; i < group.Items.Count; i++)
                {
                    batch.DrawString(group.Items[i].Name, font, position, (((group.Index >= group.Groups.Count) && (i == (group.Index - group.Groups.Count))) ? ItemSelectedColor : ItemColor), new Vector2(textScale));
                    position.Y += (font.MeasureString(group.Items[i].Name).Y*textScale);
                }
                position.X -= 10;
            }
            position.X = x1;
        }
    }

Answer 1

Never mind, the problem was solely in the GoUp function missing a simple line

else if (group.Index < -1) group.Index = -1;

the new GoUp function:

    internal bool GoUp(Group group)
    {
        if (!group.Open) return false;
        if ((group.Index >= 0) && (group.Index < group.Groups.Count) && group.Groups[group.Index].Open) if (GoUp(group.Groups[group.Index])) return true;
        group.Index--;
        if (group.Index == -1) return true;
        else if (group.Index < -1) group.Index = -1;
        if ((group.Index >= 0) && (group.Index < group.Groups.Count) && group.Groups[group.Index].Open) group.Groups[group.Index].Index = ((group.Groups[group.Index].Groups.Count + group.Groups[group.Index].Items.Count) - 1);
        return (group.Index >= 0);
    }