KelloCharts for Android

Kotlin Charts/graphs library for Android compatible with API 21+ (Android 5.0), several chart types with support for scaling, scrolling and animations Works best when hardware acceleration is available, so API 14+(Android 4.0) is recommended. Apache License 2.0.

Build badges and gradle availability coming soon

Features

• Line chart(cubic lines, filled lines, scattered points)
• Column chart(grouped, stacked, negative values)
• Pie chart
• Bubble chart
• Combo chart(columns/lines)
• Preview charts(for column chart and line chart)
• Zoom(pinch to zoom, double tap zoom), scroll and fling
• Custom and auto-generated axes(top, bottom, left, right, inside)
• Animations

Screens and Demos

• Code of a demo application is in kellocharts-sample directory
• Demo App coming soon

Usage

Every chart view can be defined in layout xml file:

   <co.csadev.kellocharts.view.LineChartView
       android:id="@+id/chart"
       android:layout_width="match_parent"
       android:layout_height="match_parent" />

or created in code and added to layout later:

   LineChartView chart = new LineChartView(context)
   layout.addView(chart)

Use methods from *Chart classes to define chart behaviour, example methods:

   Chart.isInteractive = isInteractive
   Chart.zoomType = zoomType
   Chart.setContainerScrollEnabled(boolean isEnabled, ContainerScrollType type)

Use methods from data models to define how chart looks like, example methods:

   ChartData.axisXBottom = axisX
   ColumnChartData.isStacked = isStacked
   Line.strokeWidth = strokeWidthDp

Every chart has its own method to set chart data and its own data model, example for line chart:

   arrayListOf(PointValue(0, 2), PointValue(1, 4), PointValue(2, 3), PointValue(3, 4))

   val line = Line(values, color = Color.BLUE, isCubic = true)
   val lines = arrayListOf(line)

   val data = LineChartData(lines)

   val chart = LineChartView(context)
   chart.lineChartData = data

Also, available as a DSL, same example as above:

lineData {
   lines {
       line {
           color = Color.BLUE
           isCubic = true
           pointValues {
               point {
                   x = 0f
                   y = 2f
               }
               point {
                   x = 1f
                   y = 4f
               }
               point {
                   x = 2f
                   y = 3f
               }
               point {
                   x = 3f
                   y = 4f
               }
           }
       }
   }
}

After the chart data has been set you can still modify its attributes but right after that you should call *.*ChartData setter again to let chart recalculate and redraw data. There is also an option to use copy constructor for deep copy of chart data. You can safely modify copy in other threads and pass it to *.*ChartData setter later.

Contributing

Yes :) If you found a bug, have an idea how to improve library or have a question, please create new issue or comment existing one. If you would like to contribute code fork the repository and send a pull request.

License

KelloCharts
Copyright 2018 Charles Anderson

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

 KelloCharts library is developed from the original HelloCharts library available:
   https://github.com/lecho/hellocharts-android

 KelloCharts library uses code from InteractiveChart sample available 
 on Android Developers page:
 
   http://developer.android.com/training/gestures/scale.html