The problem I face is that I want to add Views (Entry, Button, Label etc…) dynamically into a Page, meaning that I don’t know how many of each of them are to be displayed so I can’t code them in directly into Xaml. I was thinking about creating an ObservableCollection list of Views in my viewmodel, add the views into the list and somehow bind them to a CollectionView in the xaml file to dynamically display each of them. But That did not work out (the code i tried):
<CollectionView ItemsSource="{Binding CustomFieldViews}">
<CollectionView.ItemTemplate>
<DataTemplate>
<ContentView>
<ContentView.Content>
<ContentPresenter Content="{Binding}" />
</ContentView.Content>
</ContentView>
</DataTemplate>
</CollectionView.ItemTemplate>
</CollectionView>
I have been struggling with this for a long time. It displays and works correctly in debug mode but not in release mode.
Does anyone know how I can solve this problem? How can I dynamically add Views to a Page?
create a layout container for the Views
<StackLayout ... x:Name="ViewContainer" />
then dynamically create and add them to the container
Button btn = new Button() { ... };
ViewContainer.Children.Add(btn);
3
I am not using MAUI, but I know how to implement a solution for your code to make it work. However, that said, it is not recommended. Essentially, this approach works against the principles of the MVVM pattern.
Instead, you can make use of the ItemTemplateSelector attribute if you are working with a UIElement that has a compatible ItemsSource attribute. The ItemTemplateSelector allows you to use a method in an object to dynamically select a DataTemplate. Here’s an example:
<ListBox ItemsSource="{Binding}" DataContext="{DynamicResource ListofData}" ItemTemplateSelector="{StaticResource DCE}" />
In this example, you would define a custom class inheriting from DataTemplateSelector:
class DynamicContentElement : DataTemplateSelector
{
public DataTemplate TextBoxTemplate { get; set; }
public DataTemplate CheckBoxTemplate { get; set; }
public override DataTemplate SelectTemplate(object item, DependencyObject container)
{
return item is Data ? CheckBoxTemplate : TextBoxTemplate;
}
}
This class returns either a predefined CheckBoxTemplate or TextBoxTemplate based on the type of the data item.
To make this work, you also need to define the required DataTemplates in the Resources section of your UserControl. For example:
<UserControl.Resources>
<ResourceDictionary>
<DataTemplate x:Key="TextBoxTemp">
<DataTemplate.Resources>
<List x:Key="ListofData" />
</DataTemplate.Resources>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="250"/>
<ColumnDefinition Width="250"/>
</Grid.ColumnDefinitions>
<TextBlock Text="{Binding Name}" Grid.Column="0"/>
<TextBox Text="{Binding Value}" Grid.Column="1" Tag="{Binding}"/>
</Grid>
</DataTemplate>
<DataTemplate x:Key="CheckBoxTemp">
<DataTemplate.Resources>
<List x:Key="ListofData"/>
</DataTemplate.Resources>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="250"/>
<ColumnDefinition Width="250"/>
</Grid.ColumnDefinitions>
<TextBlock Text="{Binding Name}" Grid.Column="0"/>
<CheckBox IsChecked="{Binding boolValue}" Grid.Column="1" Tag="{Binding}" />
</Grid>
</DataTemplate>
<klassen:DynamicContentElement x:Key="DCE" TextBoxTemplate="{StaticResource TextBoxTemp}" CheckBoxTemplate="{StaticResource CheckBoxTemp}" />
</ResourceDictionary>
</UserControl.Resources>
With this setup, the ItemTemplateSelector dynamically assigns the correct DataTemplate to each item in your list based on its type.
Hope it helps 🙂
1