Model vs Widgets

[LukeSkyw]

I have a model which is an ArrayList of strings. I want to display that in a ListView. The array can change from time to time depending on user input (add, remove, edit).

My ListView is initialized with a widgetBuilder (as the fuzzy,zig example).

Creating a Text widget on the fly in the widgetBuilder don't seem to work:

  return (vaxis.vxfw.Text{ .text = self.some_array.items[idx] }).widget();

This only works if the text field is initialized with a string literal ("hello"). Is it because the Text here is a temporary? Calling .widget() seems to create an intermediate object with the Text object as a field. This function don't have access to the context and its arena allocator.

Or should I create a separate list of Text widgets in the model than needs to be synced with the original model? This seems to work but it's not really DRY and will be a source of bugs.

Any guidance is appreciated.

[Justus2308]

Yeah, the problem is that your Text.widget() is immediately invalidated as soon as widgetBuilder returns because it refers to a dangling stack pointer. You'll have to provide widget with a pointer that's stable throughout the entire drawing process.

To achieve that you could just use an ArrayList(vxfw.Text) to store your user input, that way you'll have stable pointers for widget() to work with as long as you only modify the array list from the same thread that does the drawing.
The scroll example does something similiar, though it doesn't store vxfw.Text directly but implements its own ModelRow.widget for the builder to use and generates a Text on the fly for each row during the drawing process.