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Query1: Show the sum of all values instead of single.
You can only display the y value with respect to the total sum using the following code snippet.
(series as PieSeries).AdornmentsInfo.SegmentLabelContent = LabelContent.YofTot;
Query2: Show the value inside or near the chart when using the pie chart series
We can set the labels position using LabelPosition property as shown in the below code snippet.
(series as PieSeries).LabelPosition = CircularSeriesLabelPosition.Outside;
Query3: Column chart keeps having problems displaying the x-axis label, showing only numbers. However, in the designer view (during debug) the labels appear ok.
We are unable to reproduce the reported problem. Could you please reproduce the problem in the provided sample below which will be helpful to provide you a solution.
Note: If the x is numerical axis then only the numbers will be displayed.