Listview tabulation

The code (c++) below is what I’m using to generate a inventory listview.
Is there a better way to make indentation in a listview?

/// loop through inventory items and add to listview if there is one or more
for (int i=0; i < item_count; i++)
{
    if (item_num[i] > 0)
    {
        auto* text = new Text(context_);
        text->SetStyleAuto();

        /// get string lenght and add spaces to make all equal length
        int str_length = strlen(item_name[i]);
        std::stringstream ss;
        ss << item_name[i];
        for (int i=0; i < (18 - str_length); i++)
        {
            ss << " ";
        }
        /// add item amount last
        ss << item_num[i];

        text->SetText(ToString(ss.str().c_str()));
        text->SetName(ToString(item_name[i]));
        list_name->AddItem(text);
    }
}

btw. it looks like this:

Use LM_HORIZONTAL layout to the parent view.

SharedPtr<UIElement> lineContainer(new UIElement(context_));
lineContainer->SetLayout(LM_HORIZONTAL, 20); // 20 pixel spacing between items in the lineContainer

// Add multiple Text elements to the lineContainer
auto* text1 = new Text(context_);
text1->SetStyleAuto();
text1->SetFixedWidth(100);
lineContainer->AddChild(text1);

auto* text2 = new Text(context_);
text2->SetStyleAuto();
text2->SetFixedWidth(100);
lineContainer->AddChild(text2);

list_name->AddItem(lineContainer);

Let me know if this helps.

I must be doing it wrong, cause I can’t make this work inside the listview.

edit: perhaps my problem is not describing the problem right.
what I want is to have a listview-format something like this:

shortname          amount    value
amuchlongername    amount    value

edit2: Yes… I’m an idiot
what I meant to write was tabulation (as you might have guessed, English is not my native tounge)