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| 1 | +--- |
| 2 | +title: Adjusting Spacing Between Legend Icon and Text in Telerik UI for .NET MAUI Pie Chart |
| 3 | +description: Learn how to control the spacing between the legend icon and text in the Pie Chart of Telerik UI for .NET MAUI. |
| 4 | +type: how-to |
| 5 | +page_title: Control Spacing Between Legend Icon and Text in .NET MAUI Chart |
| 6 | +meta_title: Control Spacing Between Legend Icon and Text in .NET MAUI Chart |
| 7 | +slug: control-spacing-legend-icon-text-maui-chart |
| 8 | +tags: chart, ui for .net maui, legend, spacing, collectionview |
| 9 | +res_type: kb |
| 10 | +--- |
| 11 | + |
| 12 | +## Environment |
| 13 | + |
| 14 | +| Version | Product | Author | |
| 15 | +| --- | --- | ---- | |
| 16 | +| 11.1.0 | Telerik UI for .NET MAUI Chart | [Dobrinka Yordanova](https://www.telerik.com/blogs/author/dobrinka-yordanova) | |
| 17 | + |
| 18 | +## Description |
| 19 | + |
| 20 | +I want to control the spacing between the legend icon and the legend text when using the [Pie Chart](https://www.telerik.com/maui-ui/documentation/controls/chart/types/pie-chart) in Telerik UI for .NET MAUI. By default, the icons and text appear very close together. |
| 21 | + |
| 22 | +This knowledge base article also answers the following questions: |
| 23 | + |
| 24 | +- How to customize the legend layout in Telerik UI for .NET MAUI Chart? |
| 25 | +- How to use CollectionView for controlling legend spacing in Charts? |
| 26 | +- How to adjust legend appearance in .NET MAUI Chart? |
| 27 | + |
| 28 | +## Solution |
| 29 | + |
| 30 | +To control the spacing between the legend icon and text, use the Telerik MAUI CollectionView and define a custom layout for the legend. Follow these steps: |
| 31 | + |
| 32 | +1. Add a `RadCollectionView` to your layout and configure its `ItemsLayout` with the desired spacing using `CollectionViewLinearLayout`. |
| 33 | +2. Define a custom `ItemTemplate` in the `RadCollectionView`. |
| 34 | +3. Use a `HorizontalStackLayout` with the `Spacing` property to control the distance between the legend icon and text. |
| 35 | + |
| 36 | +```xaml |
| 37 | +<ContentPage.Resources> |
| 38 | + <ResourceDictionary> |
| 39 | + <Style TargetType="telerik:RadCollectionViewItemView"> |
| 40 | + <Setter Property="BorderThickness" Value="0" /> |
| 41 | + <Setter Property="BorderColor" Value="Transparent" /> |
| 42 | + </Style> |
| 43 | + </ResourceDictionary> |
| 44 | +</ContentPage.Resources> |
| 45 | + |
| 46 | +<Grid RowDefinitions="400,100"> |
| 47 | + <telerik:RadPieChart x:Name="chartTest" Loaded="ChartTest_OnLoaded"> |
| 48 | + <telerik:RadPieChart.Palette> |
| 49 | + <telerik:ChartPalette> |
| 50 | + <telerik:ChartPalette.Entries> |
| 51 | + <telerik:PaletteEntry FillColor="#4FB6E7" StrokeColor="#4FB6E7" /> |
| 52 | + <telerik:PaletteEntry FillColor="#A666CE" StrokeColor="#A666CE" /> |
| 53 | + <telerik:PaletteEntry FillColor="#9DCC00" StrokeColor="#9DCC00" /> |
| 54 | + </telerik:ChartPalette.Entries> |
| 55 | + </telerik:ChartPalette> |
| 56 | + </telerik:RadPieChart.Palette> |
| 57 | + <telerik:RadPieChart.Series> |
| 58 | + <telerik:PieSeries ShowLabels="True" RadiusFactor="0.8" ValueBinding="Value" ItemsSource="{Binding Data}" /> |
| 59 | + </telerik:RadPieChart.Series> |
| 60 | + </telerik:RadPieChart> |
| 61 | + |
| 62 | + <telerik:RadCollectionView SelectionMode="None" x:Name="LegendItemsControl" Grid.Row="1"> |
| 63 | + <telerik:RadCollectionView.ItemsLayout> |
| 64 | + <telerik:CollectionViewLinearLayout Orientation="Horizontal" ItemSpacing="15" /> |
| 65 | + </telerik:RadCollectionView.ItemsLayout> |
| 66 | + <telerik:RadCollectionView.ItemTemplate> |
| 67 | + <DataTemplate x:DataType="local:LegendItem"> |
| 68 | + <HorizontalStackLayout Spacing="15"> |
| 69 | + <telerik:RadBorder BackgroundColor="{Binding SeriesPaletteEntry.FillColor}" WidthRequest="40" HeightRequest="40" /> |
| 70 | + <Label Text="{Binding SeriesDisplayName}" FontSize="12" VerticalOptions="Center" FontAttributes="Bold" /> |
| 71 | + </HorizontalStackLayout> |
| 72 | + </DataTemplate> |
| 73 | + </telerik:RadCollectionView.ItemTemplate> |
| 74 | + </telerik:RadCollectionView> |
| 75 | +</Grid> |
| 76 | +``` |
| 77 | + |
| 78 | +4. Bind the legend items to the `RadCollectionView` in the code-behind. |
| 79 | + |
| 80 | +```csharp |
| 81 | +public partial class MainPage : ContentPage |
| 82 | +{ |
| 83 | + private readonly ObservableCollection<LegendItem> legendItems = new(); |
| 84 | + |
| 85 | + public MainPage() |
| 86 | + { |
| 87 | + InitializeComponent(); |
| 88 | + this.BindingContext = new ViewModel(); |
| 89 | + this.LegendItemsControl.ItemsSource = legendItems; |
| 90 | + } |
| 91 | + |
| 92 | + private void ChartTest_OnLoaded(object sender, EventArgs e) |
| 93 | + { |
| 94 | + foreach (var series in chartTest.Series) |
| 95 | + { |
| 96 | + var source = (ObservableCollection<CategoricalData>)series.ItemsSource; |
| 97 | + foreach (var item in source) |
| 98 | + { |
| 99 | + var displayName = item.Category; |
| 100 | + var colorIndex = source.IndexOf(item) % chartTest.Palette.Entries.Count; |
| 101 | + this.legendItems.Add(new LegendItem |
| 102 | + { |
| 103 | + SeriesPaletteEntry = chartTest.Palette.Entries[colorIndex], |
| 104 | + SeriesDisplayName = displayName.ToString(), |
| 105 | + }); |
| 106 | + } |
| 107 | + } |
| 108 | + } |
| 109 | +} |
| 110 | +``` |
| 111 | + |
| 112 | +5. Add a sample `ViewModel`, `DataItem` and `LegendItem`: |
| 113 | + |
| 114 | +```csharp |
| 115 | +public class ViewModel |
| 116 | +{ |
| 117 | + public ObservableCollection<CategoricalData> Data { get; set; } |
| 118 | + |
| 119 | + public ViewModel() |
| 120 | + { |
| 121 | + this.Data = GetCategoricalData(); |
| 122 | + } |
| 123 | + |
| 124 | + private static ObservableCollection<CategoricalData> GetCategoricalData() |
| 125 | + { |
| 126 | + return new ObservableCollection<CategoricalData> |
| 127 | + { |
| 128 | + new CategoricalData { Category = "Greenings", Value = 52 }, |
| 129 | + new CategoricalData { Category = "Perfecto", Value = 19 }, |
| 130 | + new CategoricalData { Category = "NearBy", Value = 82 }, |
| 131 | + new CategoricalData { Category = "Family", Value = 23 }, |
| 132 | + new CategoricalData { Category = "Fresh", Value = 56 }, |
| 133 | + }; |
| 134 | + } |
| 135 | +} |
| 136 | + |
| 137 | +public class CategoricalData |
| 138 | +{ |
| 139 | + public object Category { get; set; } |
| 140 | + public double Value { get; set; } |
| 141 | +} |
| 142 | + |
| 143 | +public class LegendItem : NotifyPropertyChangedBase |
| 144 | +{ |
| 145 | + private string seriesDisplayName; |
| 146 | + private PaletteEntry seriesPaletteEntry; |
| 147 | + |
| 148 | + public PaletteEntry SeriesPaletteEntry |
| 149 | + { |
| 150 | + get => seriesPaletteEntry; |
| 151 | + set => UpdateValue(ref seriesPaletteEntry, value); |
| 152 | + } |
| 153 | + |
| 154 | + public string SeriesDisplayName |
| 155 | + { |
| 156 | + get => seriesDisplayName; |
| 157 | + set => UpdateValue(ref seriesDisplayName, value); |
| 158 | + } |
| 159 | +} |
| 160 | +``` |
| 161 | + |
| 162 | +## See Also |
| 163 | + |
| 164 | +- [Pie Series](https://www.telerik.com/maui-ui/documentation/controls/chart/series/pie/pie-series) |
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