# Calendar Heatmap Chart

Source: https://lumeo.nativ.sh/components/charts/calendar-heatmap

# Calendar Heatmap Chart

Display data density across a calendar year, similar to GitHub contribution graphs. Each cell represents a day, with color intensity showing the value.

## Installation

.NET CLI PackageReference Lumeo CLI

dotnet add package Lumeo.Charts

One-time app setup (`AddLumeo()`, CSS & JS) is covered in the [installation guide](docs/introduction).

## Usage

@using Lumeo

<CalendarHeatmapChart />

Preview Code

Contribution Calendar

Preview Code

Loading state

Simulate loading

Hold skeleton open

Duration: 2s 

Cycle: 1400 ms 

Shape-aware skeleton with reserved space for legend and axes — no layout shift when real data arrives.

## API Reference

### CalendarHeatmapChart

Property

Type

Default

Description

Data

object?

null

Calendar data as \[date, value\] pairs.

Year

int

current year

The year to display.

VisualMapMin

double

0

Minimum value for color mapping.

VisualMapMax

double

10

Maximum value for color mapping.

Colors

List<string>?

null

Custom color range (defaults to green shades).

IsLoading

bool

false

When true, renders a shape-matched loading skeleton in place of the chart. Bind to your async fetch state.

ShowLoadingSkeleton

bool

true

Set to false to opt out of the skeleton (chart area stays empty while IsLoading is true).

SkeletonKind

ChartSkeletonKind

(chart default)

Override the skeleton silhouette (Bars, Line, Area, Pie, Scatter, Grid, Generic).

SkeletonStyle

ChartSkeletonStyle

Phantom

Phantom renders the real chart with placeholder data and morphs to real data via ECharts animation. Silhouette falls back to the legacy SVG skeleton overlay.

ShowLoadingLabel

bool

true

Shows a small "Loading…" pill in the top-right corner whenever `IsLoading` is true. Layered on top of any `SkeletonStyle`. Set to false for bare visuals. **(rc.18)**

LoadingText

string?

"Loading…"

Label rendered next to the spinner inside the loading pill. Set to empty to show the spinner alone. **(rc.18)**

ShowTooltip

bool

true

Enables the hover tooltip showing date and value.

Width

string

"100%"

CSS width of the chart container.

Height

string

"350px"

CSS height of the chart container.

Theme

string?

null

Optional ECharts theme name override.

PhantomCycleMs

int

1400

Phantom-mode refresh interval in milliseconds. Lower = faster data cycling while loading.

ShowDataLabels

bool

false

When true, displays value labels inside each calendar cell.

LabelPosition

string

"inside"

Position of data labels relative to each cell.

LabelFormat

string?

null

Optional ECharts label formatter string for cell labels.

DataZoom

bool

false

Enables the interactive data-zoom slider beneath the chart.

Toolbox

bool

false

Shows the ECharts toolbox with export and zoom controls.

ColorPalette

List<string>?

null

Alternate full color palette applied to the chart.

AnimationDuration

int?

null

Animation duration in milliseconds when data changes.

AnimationEasing

string?

null

ECharts easing function name for animation curves.