Get started

1. Add the packages

dotnet add package AvCharts.Controls

AvCharts.Controls brings the chart control, data tips, the legend and the colour tokens, and depends on AvCharts - the model half, which is axes, transforms, series and the drawing kernel, and which never touches Avalonia.Controls.

2. Dress the page

Every colour a chart draws is a token in one resource dictionary, in a light and a dark set. One line, and every chart on the page is dressed:

<Application.Resources>
    <ResourceInclude Source="avares://AvCharts.Controls/Themes/ChartTheme.axaml" />
</Application.Resources>

Overriding a token is putting a value under the same key; replacing the look outright is writing your own ControlTheme under the same type key. A chart follows the variant of whatever it is put into, so a dark chart on a light page is a ThemeVariantScope and nothing more.

3. Draw a line

using Avalonia.Controls;
using AvCharts.Charts;
using AvCharts.Controls;

var chart = new CartesianChart
{
    HorizontalAxis = new DateTimeAxis(),
    VerticalAxis = new LinearAxis(),
};

chart.Series.Add(new LineSeries<Reading>
{
    DisplayName = "Depth",
    ItemsSource = readings,
    XSelector = reading => reading.When,
    YSelector = reading => reading.Depth,
});

// A column chart with a line over it is two series on one chart, and a second
// vertical scale is a series with an axis of its own.
chart.Series.Add(new ColumnSeries<Reading> { /* ... */ });

A series can be a line, a step line, an area, a plot of marks, a bubble, a column or a bar, and columns come clustered, overlaid or stacked. The gallery has a page for each of those, with knobs on it.

Where to go next

What it is built for

• Many readings, not many charts. A hundred thousand read and drawn in about thirty milliseconds; a frame of panning in twelve; a hit test on them in seventy microseconds. Sampling is built in, and it is applied where the readings are, not by asking for less data.
• Readings that are missing are said to be missing. A gap, a line joined over it, or a zero - never an invented value.
• The window belongs to the reader. Wheel zoom anchored at the pointer, drag panning, and a fixed scale where a unit of data keeps its pixels whatever the control's size.
• Extension is a shape, not an inheritance tree. A custom series is four overrides; a custom axis brings its own ladder of intervals; a marker is an interface; a threshold or a band is a chart element; a coordinate system of your own is a transform.