Edge Documentation

Using Sparklines To Show Historical Trend

The Sparkline column renderer is a special option for presenting data in the column of a Table Widget.

A Sparkline is a very small line chart, without axes or coordinates, that presents the general shape of variation in some measurement, such as temperature or stock market price, in a simple and highly condensed way. Using alternate methods, such as Actions to drill-down and provide details, or to update an on-screen Widget, may not provide the immediate context and ability to compare items within a table that can be achieved with a Sparkline.

The Sparkline option is only applicable for columns that have a one-to-many association where the “many” association represents the data points used in the sparkline.

How To Create a Sparkline

Perform the following steps to create a Sparkline column in a Table Widget:

1. Log in to AppBoard as administrator.
2. Create a Table Widget.
3. Add one or more columns of data to the Widget.
4. For a desired Data Field, select Sparkline as the Column Renderer.
5. Click Customize to configure the Sparkline:
   • Header Text - The name to be displayed for the column.
   • Column Width - The default width for the display of the column in the table.
   • Resizable - Check the box if you want the User to be permitted to change the width of the column.
   • X Axis Field - Select the desired data field to use for the X-Axis of the Chart. For more details, see Area Chart Widget.
   • X Axis Type - Select an option for Type from the drop-down box. This will be used to determine how the data is translated by AppBoard into the labels that are shown along the x-axis. For more details, see Area Chart Widget.
   • Y Axis Field - Select the desired data field to use for determining the height for that series. For more details, see Area Chart Widget.
   • Minimum Value - Select the lowest Y Axis value to display, for purposes of controlling which portion of the results to display.
   • Maximum Value - Select the highest Y Axis value to display, for purposes of controlling which portion of the results to display.
   • Chart Type - Select "Area" for an area-based Sparkline or "Line" for a line-based Sparkline. This controls whether there is shading of the region beneath the displayed values. The "Area" option will include shading.
   • Chart Color Rules - Configure conditions that modify the color of the Sparklines, based on evaluation of fields in the underlying data.

Sample Data

Perform the following steps to create a Sparkline column in a Table Widget using sample data:

1. Create a Data Source called sparkline, using the CSV data directory in /pkg/appboard/tutorial/sparkline
   • For "Header Meta Delimiter", make sure "Asterisk" is selected.
2. Add the following association on the Associate panel of the Data Source Wizard:
   • sparkline.sparkline_services.Service - EQUALS - sparkline.sparkline_svc_history.Service
   • Name: "history"
   • Type: "One To Many"
   • Publish: "Always"
3. Create a Basic Table Widget and place it on a Stack.
4. Select "sparkline.sparkline_services" as the Data Collection for the Widget.
5. Configure the following columns for the Basic Table Widget:
   • Service: Status Shape
   • Service: Text
   • Availability: Text
   • history: Sparkline
6. Click Customize and configure the Sparkline as follows:
   • Header Text - Service History
   • Column Width - 150
   • X Axis Field - Datetime
   • X Axis Type - DateTimeAxis
   • Y Axis Field - Availability
   • Minimum Value - 0
   • Maximum Value - 100
   • Chart Type - Area
   • Chart Color Rules - [None]
   • Default Chart Color - Select a color.
   • [optional] Add a Chart Color Rule that is red when Availability <= 90 and green when Availability > 90.
7. Click Save Changes, Next, and Finish.
8. Observe that the Table Widget in the builder display has a Sparkline Column labeled "Service History".