Event handlers

In Maui, you can add functionality to user interface controls by handling events. For each EventHandler in a Sharp.UI class, a fluent helper method is generated to make it easier to attach an event handler to the control.

For example, in the case of the Clicked event handler in the Button class, two fluent methods are generated:

• OnClicked(Button sender)
• OnClicked(object sender, EventArgs e)

Here's an example of how you can use the fluent helper method OnClicked to handle the Clicked event on a Button control:

using Sharp.UI;

public class HelloWorldPage : ContentPage
{
    int count = 0;
    protected override View Build()
    {
        return new VStack
        {
            ...
            new Button("Click me")
                .OnClicked(OnCounterClicked)
        };
    }

    private void OnCounterClicked(Button sender)
    {
        count++;
        sender.Text = $"Clicked {count} ";
        sender.Text += count == 1 ? "time" : "times";
    }
}

Or, you can use an inline function to handle the event:

new Button("Click me")
    .OnClicked(button =>
    {
        count++;
        button.Text = $"Clicked {count} ";
        button.Text += count == 1 ? "time" : "times";
    })

This makes it easy to attach event handlers to controls in a concise and readable way.