Auto Adjust Axis for Current Viewport

[Carl Herlitz]

Hi, I have a question similar to this: http://www.telerik.com/forums/y-axis-values-on-radcartesianchart-with-zoom.

I'd like for the y-axis to auto-adjust its range based off of just the data points displayed, not the entire collection. And it should happen as the user scrolls/zooms. I understand how the solution you provided in the previous forum post works, but it wouldn't work for me because I have many different charts with a variable number of series, different data points being charted, etc.

So, my questions

1) Since the forum post I linked above, have you added the ability to auto-adjust an axis off the current viewport rather than the entire data set?

2) If not, can you think of a generic version of the sample in the previous forum post? One where I don't have to access a series' ItemsSource? I noticed that in the sample, there's this line of code in MainWindow.xaml.cs that gets the range using the series' ItemsSource (Context).

var visibleRange = Context.GetRange(firstElem, lastElem - firstElem).Select(pd => pd.YVal);

How can I replace that with something that can give me the max y-axis values of all chart series within a range? Can I get a collection of all the visible DataPoints? This would also have to work with stacked bar charts, where I'd like to get the total y-axis value of each set of stacked bars.

I attached a screenshot to visualize the issue. The bars are so small because somewhere else in the chart, there's a data point where the max value of both bars, stacked, is about 2.2 million. When a user scrolls to see the data points in the screenshot, the y axis max value should change to probably be about 500K.

[Martin Ivanov]

Hi Carl,

No, still there is no auto range feature in RadCartesianChart. However, we have a feature request in our system which you can follow in order to track its status. 

As for your second question, in order to adjust the example from the forum for a scenario with multiple series you will need to write additional code. The chart itself doesn't expose a single collection with all plotted data points. Instead, you will iterate through its Series collection and get their data points through the DataPoints collection. This way you can get the Y axis values for all series. For your convenience I updated the example from the forum post to demonstrate such approach. Please give it a try and let me know if it works for you.

Regards,
Martin
Telerik