|Part 3: Extending TestArchitect / Lesson #9: Creating Dashboard panels|
In this activity, you will create a stacked bar chart, which is useful for visualizing changes in relative amounts of some quantities over a given range.
In the section Creating a chart, you created a pie chart that indicated the relative numbers of Passed, Failed, and Passed with Warnings/Errors results that occurred over a period of time. But how might you observe how those proportions have changed over time? One option would be to generate multiple pie charts, using filters to specify a different time range for each. But a better solution is to create a single stacked bar chart.
The stacked bar chart consists of a sequence of bars, distributed horizontally over a given range. (In this instance, that range would be time.) Each bar is composed of two or more stacked, color-coded "sub-bars". In our case, a given colored sub-bar represents a particular result outcome, and its size represents the number of occurrences of that outcome for that particular time period. A stacked bar chart in this case also has the advantage of indicating the total number of tests performed in each time period, relative to the other periods. That information is given by the overall height of each bar in the chart.
Once again, you can make use of the existing Test Results (unfiltered) data profile, which provides test results from all the historical Car Rental tests. Also note that the Category and Series values, as with your earlier line chart, are again Date of run and Result.