plotter only plot the time, not the date - datetime

Question

im trying to follow this guide on plotting a time series chart but ive run into a small issue. is there any way to change the bottom label to only show the current time (H:M:S) instead of the current date? ive been trying for a while now to find a way to do this but it still havent been able to. im following the code in the guide so this is the code im working with:
use plotters::prelude::*;
use chrono::{Utc, TimeZone};
fn main() {
let root_area = BitMapBackend::new("images/2.11.png", (600, 400))
.into_drawing_area();
root_area.fill(&WHITE).unwrap();
let start_date = Utc.ymd(2019, 10, 1);
let end_date = Utc.ymd(2019, 10, 18);
let mut ctx = ChartBuilder::on(&root_area)
.set_label_area_size(LabelAreaPosition::Left, 40)
.set_label_area_size(LabelAreaPosition::Bottom, 40)
.caption("MSFT daily close price", ("sans-serif", 40))
.build_cartesian_2d(start_date..end_date, 130.0..145.0)
.unwrap();
ctx.configure_mesh().draw().unwrap();
ctx.draw_series(
LineSeries::new(
(0..).zip(DATA.iter()).map(|(idx, price)| {
let day = (idx / 5) * 7 + idx % 5 + 1;
let date = Utc.ymd(2019,10, day);
(date, *price)
}),
&BLUE,
)
).unwrap();
}
const DATA: [f64; 14] = [ 137.24, 136.37, 138.43, 137.41, 139.69, 140.41, 141.58, 139.55, 139.68, 139.10, 138.24, 135.67, 137.12, 138.12];
ive tried using chrono's NaiveTime but it doesnt seem to be supported, DateTime causes the entire date and time to be printed instead of just the time, and ive also tried creating my own element series but i cant figure out how to get that working. anyone have any ideas?

Answer 1

You can add this line, or something like it to the ChartBuilder:
.x_label_formatter(&|x| format!("{:02}:{:02}", x.hour(), x.minute()))
where x is a DateTime struct. You can use other DateTime functions to get different parts of the time, as required.