Last Updated: 07 Apr 2020 08:53 by ADMIN
Created on: 19 Aug 2019 15:25
Category: Chart
Type: Feature Request
PieChart: PieSeries should have LabelFontSize LabelFontAttributes LabelFontFamily LabelTextColor LabelMargin like other charts (and Gauges) provide

Using the RadPieChart and PieSeries (UI for Xamarin v2019.2.802.1 from NuGet), I can currently set the LabelBinding (or LabelFormat or LabelFormatter) to adjust the strings displayed in the labels on the slices of the pie chart, but unlike other chart controls, I currently have no way to modify the styling of those labels like I can in every other chart control I've used from Telerik UI for Xamarin.

It seems to me that it would be best to have more properties on the PieSeries class, like LabelFontSize, LabelFontAttributes, LabelFontFamily, LabelTextColor, and LabelMargin (Label prefix to distinguish from LegendTitleBinding could be kept or discarded as desired on some of these names).

LabelMargin would be particularly helpful to eliminate the UWP situation wherein currently all pie slice labels overlap with the outer lighter ring of the pie chart (see image from UWP).  The others just seem needed to maintain a consistent appearance of charts within an app - if all my chart labels are dark blue and a different font size and style except for the not-style-able black labels in pie charts, that makes pie charts hard to incorporate without looking bad or forcing styling elsewhere to match the pie charts' fixed values.

Posted on: 20 Aug 2019 11:46

Thank you for the provided image and detailed explanation.

I am glad to hear you have used the LabelFormat property of the PieChart.

I agree with you that the PieChart should provide styling properties for its Series Labels. I have updated the status of the Feedback item to "Under Review". We will keep an eye on it and will schedule it if there is a demand.

Regarding to the Labels visualization per platform, this behavior comes from the native chart. Mainly, iOS, Android and UWP charts are three different controls and do not have 100% matching across all the platforms.

Additional information:

Chart controls could be further customized (per platform) through a custom renderer. More information about this can be found here. You can also take a look at the native Android Chart and native iOS Chart documentation. 

Progress Telerik
Posted on: 19 Aug 2019 22:22
*on top of all pie palette colors as well as on top of the outside-of-the-pie background color.
Posted on: 19 Aug 2019 22:19
Also noteworthy is that even though the different platform renderings of these labels puts them on different backgrounds, the developer configuring the PieSeries could still apply either platform specific colors using OnPlatform, or a single color that works fine on all pie palette colors as well as the outside-the-pie background color.