MAUI-988662 - [Others] Updated UG for how to display tooltip and datalabels in release mode

maui-toolkit-toc.html

@@ -168,6 +168,7 @@
             <li><a href="/maui-toolkit/cartesian-charts/Add-custom-labels">Add custom labels to the chart axis</a></li>
             <li><a href="/maui-toolkit/cartesian-charts/Customize-each-chart-axis-label">Customize each chart axis label using the callback event</a></li>
             <li><a href="/maui-toolkit/cartesian-charts/Get-the-data-point-collection-based-on-region">Get the data point collection based on region</a></li>
+            <li><a href="/maui-toolkit/cartesian-charts/Why-tooltip-and-data-labels-not-visible-in-release-mode">Why tooltip and data labels not visible in release mode</a></li>
 		</ul>
 	   </li>
         </ul>

maui-toolkit/Cartesian-Charts/Why-tooltip-and-data-labels-not-visible-in-release-mode.md

@@ -0,0 +1,79 @@
+---
+layout: post
+title: Show tooltip and datalabels in release mode | Syncfusion
+description: Learn here all about displaying tooltip and datalabels in release mode in SfCartesianChart in Syncfusion® .NET MAUI Chart (SfCartesianChart) control.
+platform: maui-toolkit
+control: SfCartesianChart
+documentation: ug
+keywords: .NET MAUI chart tooltip, .NET MAUI chart data label, TooltipInfo Item binding, ChartDataLabel Item binding, Release mode trimming, Preserve attribute MAUI.
+---
+
+# Display tooltip and data labels in release mode
+
+In [SfCartesianChart](https://help.syncfusion.com/cr/maui-toolkit/Syncfusion.Maui.Toolkit.Charts.SfCartesianChart.html), the binding context inside tooltip and data label templates is not your business model directly. These templates run with Chart specific contexts.
+
+* Tooltip template: chart:[TooltipInfo](https://help.syncfusion.com/cr/maui-toolkit/Syncfusion.Maui.Toolkit.Charts.TooltipInfo.html)
+* Data label template: chart:[ChartDataLabel](https://help.syncfusion.com/cr/maui-toolkit/Syncfusion.Maui.Toolkit.Charts.ChartDataLabel.html)
+
+Both provide an `Item` property that references the actual data object from the series [ItemsSource](https://help.syncfusion.com/cr/maui-toolkit/Syncfusion.Maui.Toolkit.Charts.ChartSeries.html#Syncfusion_Maui_Toolkit_Charts_ChartSeries_ItemsSourceProperty). Bind your fields through Item to display values from your business model.
+
+Release builds can remove types that are referenced only from XAML. To prevent this, reference a value converter from XAML and preserve your ViewModel, business model, and converter classes. With .NET 9 compiled bindings, set **x:DataType="chart:TooltipInfo"** for tooltip templates and **x:DataType="chart:ChartDataLabel"** for data label templates, then bind via Item. Use the converter to extract the required property from Item.
+
+
+{% highlight xaml %}
+
+    <chart:SfCartesianChart>
+        <chart:SfCartesianChart.Resources>
+            <local:ValueConverter x:Key="valueConverter" />
+
+            <DataTemplate x:Key="tooltiptemplate">
+                <StackLayout x:DataType="chart:TooltipInfo" Orientation="Vertical">
+                    <Label Text="{Binding Item, Converter={StaticResource valueConverter},
+                                          ConverterParameter=Planned,
+                                          StringFormat='Planned : {0}h'}"
+                           TextColor="White" />
+                </StackLayout>
+            </DataTemplate>
+
+            <DataTemplate x:Key="labelTemplate">
+                <StackLayout x:DataType="chart:ChartDataLabel" Orientation="Vertical">
+                    <Label Text="{Binding Item, Converter={StaticResource valueConverter},
+                                          ConverterParameter=Planned,
+                                          StringFormat='Label : {0}h'}"
+                           TextColor="Black" />
+                </StackLayout>
+            </DataTemplate>
+        </chart:SfCartesianChart.Resources>
+
+        <chart:SplineAreaSeries x:Name="series"
+                                ItemsSource="{Binding ChartData}"
+                                XBindingPath="WeekNumber"
+                                YBindingPath="Planned"
+                                EnableTooltip="True"
+                                ShowDataLabels="True"
+                                LabelTemplate="{StaticResource labelTemplate}"
+                                TooltipTemplate="{StaticResource tooltiptemplate}">
+        </chart:SplineAreaSeries>
+
+    </chart:SfCartesianChart>
+
+{% endhighlight %}
+
+
+{% highlight C# %}
+
+    public class ValueConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            return value is WeekPlan weekPlan ? weekPlan.Planned : value;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) => value;
+    }
+
+{% endhighlight %}
+
+## See also 
+
+[Why Tooltip and DataLabel Are Missing in Release Mode .NET MAUI Chart?](https://support.syncfusion.com/kb/article/21677/why-tooltip-and-datalabel-are-not-showing-in-release-mode-in-net-maui-sfcartesianchart)