.NET MAUI ComboBox Commands
ComboBox has the following commands:
-
SelectAllCommand(ICommand)—Selects all items from the source.
The
SelectAllcommand can be used only whenSelectionModeisMultiple. An exception will be thrown if the command is invoked inSingleSelectionMode.
-
ClearSelectionCommand(ICommand)—Sets the selection to null. If MultipleSelectionModeis used, this command will clear all selected items. YOu can override the default behavior and create custom command.
The example below shows both cases, the default ClearSelectionCommand execution and custom ClearSelectionCommand implementation:
<HorizontalStackLayout Spacing="5"
Margin="0, 0, 0, 12">
<Button Text="Default Clear Command"
Command="{Binding Source={x:Reference comboBox}, Path=ClearSelectionCommand}" />
<Button Text="Custom Clear Command"
Clicked="ExecuteCustomCommanClicked"/>
</HorizontalStackLayout>
<telerik:RadComboBox x:Name="comboBox"
Placeholder="Select City!"
SelectionMode="Multiple"
IsDropDownClosedOnSelection="False"
WidthRequest="{OnPlatform MacCatalyst=300, WinUI=300}"
HorizontalOptions="{OnIdiom Default=Fill, Desktop=Start}"
ItemsSource="{Binding Items}"
DisplayMemberPath="Name"
AutomationId="comboBox"/>
class CustomClearSelectionCommand : ComboBoxClearSelectionCommand
{
public override async void Execute(object parameter)
{
bool executeDefault = await App.Current.MainPage.DisplayAlert("Command", "Execute command?", "Yes", "No");
if (executeDefault)
{
base.Execute(parameter);
}
}
}
private void ExecuteCustomCommanClicked(object sender, EventArgs e)
{
this.comboBox.ClearSelectionCommand = new CustomClearSelectionCommand();
this.comboBox.ClearSelectionCommand.Execute(true);
}
