Throw the Constructor in the Trash

Throw the Constructor in the Trash" advocates for reducing class coupling by avoiding constructor dependencies, favoring techniques like Dependency Injection or Factory Patterns for flexible, maintainable, and testable code.

Understanding Constructors and OnAppearing in .NET MAUI ??

.NET MAUI (Multi-platform App UI) is a framework for creating native mobile and desktop apps with C# and XAML. In .NET MAUI, the constructor and the OnAppearing method serve different purposes, particularly when it comes to initializing components and handling dynamic data.

Constructors in .NET MAUI ??

A constructor is a special method in a class that is called when a new instance of the class is created. In the context of .NET MAUI, constructors are typically used to initialize components and set up the initial state of the page. However, constructors have their limitations, especially when dealing with dynamic data.

• Constructors are only called once when the page is first created.
• Data retrieved in the constructor won’t be refreshed unless the page is recreated.
• It’s not suitable for data that needs to be updated frequently or when the page appears.

The OnAppearing Method ??

The OnAppearing method is part of the Page lifecycle in .NET MAUI. It is called every time the page is about to be displayed on the screen. This makes it an ideal place to handle tasks that need to occur each time the page appears, such as:

• Retrieving fresh data from an API.
• Updating UI elements with new data.
• Resetting certain states when navigating back to a page.

Best Practices for Data Retrieval

When retrieving data from an API, it’s recommended to use the OnAppearing method rather than the constructor because.

• OnAppearing ensures that you get the latest data every time the page is displayed.
• It allows for a better user experience with updated information.
• It aligns with the dynamic nature of mobile applications where the state can change frequently.

Example. Implementing OnAppearing

Here’s a simple example of using OnAppearing to retrieve data .

protected override async void OnAppearing()
{
    base.OnAppearing();
    var data = await ApiService.GetDataAsync();
    // Update your UI with the retrieved data
}