Donut

Donut is an Android library which helps you to easily create beautiful doughnut-like charts.

Installation

module/build.gradle:

dependencies {
    implementation("app.futured.donut:library:$version")
}

Features

DonutProgressView is a configurable doughnut-like chart view capable of displaying multiple datasets with assignable colors. It supports animations and features a gap at the top, which makes it look like a gauge (or tasty bitten-off donut - that's why the name).

The view automatically scales it's datasets proportionally to their values once it gets filled up. This allows you to show your users their daily progresses, reached goals, etc.

Usage

Place the view in your layout

<app.futured.donut.DonutProgressView
    android:id="@+id/donut_view"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    app:donut_bgLineColor="@color/cloud"
    app:donut_gapWidth="20"
    app:donut_gapAngle="270"
    app:donut_strokeWidth="16dp"/>

Submit data to the view

val dataset1 = DonutDataset(
    name = "dataset_1",
    color = Color.parseColor("#FB1D32"),
    amount = 1f
)

val dataset2 = DonutDataset(
    name = "dataset_2",
    color = Color.parseColor("#FFB98E"),
    amount = 1f
)

donut_view.cap = 5f
donut_view.submitData(listOf(dataset1, dataset2))

You'll get something like this:

About the data cap

Once the sum of all dataset values exceeds view's cap property, the view starts to scale it's datasets proportionally to their amounts along it's length. E.g. if we, in the upper example, set cap to donut_view.cap = 1f (dataset1.amount + dataset2.amount > 1f), we would get something like this:

Submitting data

The view accepts list of DonutDataset objects that define data to be displayed.
Each DonutDataset object holds dataset's unique name (string), it's color (color int) and dataset's value. (Note: the view uses unique name for each dataset to resolve it's internal state and animations, and throws IllegalStateException if multiple datasets with same name are submitted.)

val waterAmount = DonutDataset(
    name = "drink_amount_water",
    color = Color.parseColor("#03BFFA"),
    amount = 1.2f
)

You have to submit new list of datasets everytime you want to modify displayed data, as DonutDataset object is immutable.

donut_view.submitData(listOf(waterAmount))

Granular controls

The view also provides methods for more granular control over displayed data. You can use addAmount, setAmount and removeAmount methods to add, set or remove specified amounts from displayed datasets.

Adding amount

donut_view.addAmount(
    datasetName = "drink_amount_water",
    amount = 0.5f,
    color = Color.parseColor("#03BFFA") // Optional, pass color if you want to create new dataset
)

The addAmount adds specified amount to dataset with provided name. What if dataset does not yet exist? This method has one optional color parameter (default value is null) - when called, and there isn't already displayed any dataset with provided name and color parameter was specified, the new DonutDataset with provided name, amount and color will be automatically created internally for you. If you leave the color param null while trying to add value to non-existent dataset, nothing happens.

Setting amount

donut_view.setAmount(
    datasetName = "drink_amount_water",
    amount = 2.5f
)

The setAmount methods sets specified amount to dataset with provided name. If provided amount is equal or less than 0, dataset and corresponding progress line are automatically removed after animation. If view does not contain specified dataset, nothing happens.

Removing amount

donut_view.removeAmount(
    datasetName = "drink_amount_water",
    amount = 0.1f
)

The removeAmount simply subtracts specified amount from any displayed dataset. If resulting amount is equal or less than 0, dataset and corresponding progress line are automatically removed after animation. If view does not contain specified dataset, nothing happens.

Get and clear data

If you want to get currently displayed data, call getData() method which returns immutable list of all displayed DonutDataset objects. To clear displayed data, call clear() method.

Each call to a data method (submit, add, set, remove, clear) results in view automatically resolving and animating to the new state.

Customization

The view allows you to configure various properties to let you create a unique style that fits your needs. They can be changed either via XML attributes, or at runtime via property access.

XML attributes

In addition to these XML attributes, the view features masterProgress property (0f to 1f) that can be changed programatically. It controls percentual progress of all lines, including the background line, which allows you to get creative with startup animations, etc.

Sample app

The quickest way to explore different styles is to try the sample app, which contains an interactive playground with buttons and sliders to fiddle with.

Contributors

Current maintainer and main contributor is Matej Semančík.

Licence

Donut is available under MIT license. See LICENSE file for more information.