Cannot call .stroke on LineChart / private field error

[J2ane]

Environment： gpui version: 0.2.2 gpui_component version: 0.4.0

LineChart::new(self.data.clone())
    .x(|d| d.x.clone())
    .y(|d| d.y)
    .stroke(cx.theme().success)

Diagnostics:
no method named `stroke` found for struct `LineChart<T, X, Y>` in the current scope
private field, not a method [E0599]