Question

i`d like to set colors in codebehind for every Pie Slice in my PieChart. Anyone knows how to do this? Now it gets the colors from the styles xaml, but i need to assign the colors for each value (pie slice) by myself from codebehind.

Answer 1

Not sure if this is the best way of doing it but I struggled with the same thing and eventually got it working like this.

Declare a palette:

System.Windows.Controls.DataVisualization.ResourceDictionaryCollection pieSeriesPalette = new System.Windows.Controls.DataVisualization.ResourceDictionaryCollection();

Then create a brush (or brushes) with the color information:

Brush currentBrush = new SolidColorBrush(Color.FromRgb(128, 128, 128)); //Grey

With each brush, create a new Style and add it to the palette collection:

System.Windows.ResourceDictionary pieDataPointStyles = new ResourceDictionary();
Style stylePie = new Style(typeof(PieDataPoint));
stylePie.Setters.Add(new Setter(PieDataPoint.BackgroundProperty, currentBrush));
pieDataPointStyles.Add("DataPointStyle", stylePie);
pieSeriesPalette.Add(pieDataPointStyles);

Note that each brush (or palette entry) has to be created as a new ResourceDictionary object. If you create 10 brushes and just add them all to the same ResourceDictionary the piechart will only use the first color. (Or maybe I m just doing something wrong).

Then set the chart palette to the custom palette:

this.yourChartsName.Palette = pieSeriesPalette;

This is only useful if you want to customise the palette to specific colors. For a color range or fixed list of colors I believe you can just definie the palette in XAML. Hope it helps.

Answer 2

One possiblitiy is to construct your colours from HSL or HSV, keeping the SL/SV part fixed you can divide the entire hue range into the number of pie slices you have, this should ensure they are reasonably visually seperated. different SL/SV values will make the chart vibrant colours or pastels or dark shades etc.

友情链接