@nativescript-community/ui-chart/README.md

A powerful chart / graph plugin, supporting line, bar, pie, radar, bubble, and candlestick charts as well as scaling, panning and animations.

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## Installation

-   `tns plugin add @nativescript-community/ui-chart`

---

## Migration to 2.x

In 2.x most methods like `setColor`/`getColor` have been changed to properties like `color`
You can either to it manually and update them all (you should get tsc errors for removed or renamed methods), or you can use a regexp like `/set([A-Z])(\w*?)\(/` to search and replace (first group should be lowercase in the replace) with something like `\L$1$2=(`
Then use typings to fix potential name change

## Usage

For gestures to work, make sure to add the following code block inside main application file (e.g. app.ts):

```typescript
import { install } from '@nativescript-community/ui-chart';
install();
```

You can also check [Wiki](https://github.com/nativescript-community/ui-chart/wiki) for any useful material.

## Plain NativeScript

<span style="color:red">IMPORTANT: </span>Make sure you include `xmlns:ch="@nativescript-community/ui-chart"` on the Page element.

### XML

```XML
<Page xmlns="http://schemas.nativescript.org/tns.xsd" xmlns:ch="@nativescript-community/ui-chart">
    <ScrollView>
        <StackLayout>
            <Label text="Line Chart" fontSize="20"/>
            <ch:LineChart id="line-chart" backgroundColor="lightgray" width="300" height="350" loaded="onLineChartLoaded"/>
        </StackLayout>
    </ScrollView>
</Page>
```

### TypeScript

```typescript
import { LineChart } from '@nativescript-community/ui-chart/charts/LineChart';
import { LineDataSet } from '@nativescript-community/ui-chart/data/LineDataSet';
import { LineData } from '@nativescript-community/ui-chart/data/LineData';

export function onLineChartLoaded(args) {
    const chart = args.object as LineChart;

    chart.dragEnabled = true;
    chart.scaleEnabled = true;

    const data = new Array(500).fill(0).map((v, i) => ({
        index: i,
        value: Math.random() * 1,
    }));

    const sets = [];
    const set = new LineDataSet(data, 'Legend Label', 'index', 'value');
    set.color = 'blue';
    sets.push(set);

    // Create a data object with the data sets
    const ld = new LineData(sets);

    // Set data
    chart.data = ld;
}
```

## NativeScript + Vue

```javascript
Vue.registerElement('LineChart', () => require('@nativescript-community/ui-chart').LineChart);
```

```html
<LineChart ref="chart" width="300" height="400" @loaded="onChartLoaded"> </LineChart>
```

```javascript
import { LineChart } from '@nativescript-community/ui-chart/charts/LineChart';
import { LineDataSet } from '@nativescript-community/ui-chart/data/LineDataSet';
import { LineData } from '@nativescript-community/ui-chart/data/LineData';
```

```javascript
onChartLoaded() {
    const chart = this.$refs.chart['nativeView'] as LineChart;
    chart.backgroundColor = 'white';

    chart.drawGridBackground = false;

    // enable scaling and dragging
    chart.dragEnabled = true;
    chart.scaleEnabled = true;

    // force pinch zoom along both axis
    chart.petPinchZoomEnabled = true;

    // disable dual axis (only use LEFT axis)
    chart.axisRight.enabled = false;

    const myData = new Array(500).fill(0).map((v, i) => ({
        index: i,
        value: Math.random() * 1,
    }));

    const sets = [];
    const set = new LineDataSet(myData, 'Legend Label', 'index', 'value');
    set.setColor('blue');
    sets.push(set);

    // Create a data object with the data sets
    const ld = new LineData(sets);

    // Set data
    chart.data = ld;
}
```

## NativeScript + Angular
Register the element in app.module.ts
```javascript
registerElement('LineChart', () => require('@nativescript-community/ui-chart').LineChart);
```

```html
<LineChart width="300" height="400" (loaded)="onChartLoaded($event)"> </LineChart>
```

```javascript
import { LineChart } from '@nativescript-community/ui-chart/charts/LineChart';
import { LineDataSet } from '@nativescript-community/ui-chart/data/LineDataSet';
import { LineData } from '@nativescript-community/ui-chart/data/LineData';
```

```javascript
onChartLoaded(args) {
    const chart = args.object as LineChart;
    chart.backgroundColor = 'white';

    chart.drawGridBackground = false;

    // enable scaling and dragging
    chart.dragEnabled = true;
    chart.scaleEnabled = true;

    // force pinch zoom along both axis
    chart.petPinchZoomEnabled = true;

    // disable dual axis (only use LEFT axis)
    chart.axisRight.enabled = false;

    const myData = new Array(500).fill(0).map((v, i) => ({
        index: i,
        value: Math.random() * 1,
    }));

    const sets = [];
    const set = new LineDataSet(myData, 'Legend Label', 'index', 'value');
    set.color = 'blue';
    sets.push(set);

    // Create a data object with the data sets
    const ld = new LineData(sets);

    // Set data
    chart.data = ld;
}
```

## About

This plugin is based on [MPAndroidChart](https://github.com/PhilJay/MPAndroidChart), a powerful & easy to use chart library. Therefore, special thanks goes to Philipp Jahoda, the creator of [MPAndroidChart](https://github.com/PhilJay/MPAndroidChart) and the rest of his team.

Instead of directly importing existing native libraries, this library has been rewritten in TypeScript, using [@nativescript-community/ui-canvas](https://github.com/nativescript-community/ui-canvas) plugin API as a basis. Plugin 'ui-canvas' is an extremely powerful tool that converts Android Native Canvas API to a cross-platform API for NativeScript framework. In few words, 'ui-chart' has the same code-base for both Android and iOS.

Additionally, [@nativescript-community/gesturehandler](https://github.com/nativescript-community/gesturehandler) plugin is used for handling chart gestures.

In short, these are the benefits of rewriting library into a NativeScript plugin:

-   Same codebase for Android and iOS. Makes maintaining the library very easy.
-   Smaller apps size because there are no native libs or native frameworks to consume space. All done with the power of {N}

Originally, the main goal was to prevent the need for marshalling all datasets. This is extremely heavy, costly and unnecessary!

Upon running demo samples, one can conclude it is the fastest drawing library, in comparison to `nativescript-ui-chart` and `nativescript-mpchart`.

That is because:

-   It does not marshal or recreate any subset of the data sets, but directly uses the provided array instead
-   It can share the same data array between multiple datasets
-   It can still use the power of native arrays to NOT marshal arrays of positions while drawing lines with [@nativescript-community/ui-canvas](https://github.com/nativescript-community/ui-canvas)

## Documentation

The NativeScript 'ui-chart' plugin is based on the [MPAndroidChart](https://github.com/PhilJay/MPAndroidChart) library.
In few words, its API is identical. The possibility to add API reference will be considered in the future.