XAML Compilation in Xamarin.Forms
XAML can be optionally compiled directly into intermediate language (IL) with the XAML compiler (XAMLC).
XAML compilation offers a number of a benefits:
- It performs compile-time checking of XAML, notifying the user of any errors.
- It removes some of the load and instantiation time for XAML elements.
- It helps to reduce the file size of the final assembly by no longer including .xaml files.
XAML compilation is disabled by default in the framework. However, it's enabled in the templates for new projects. It can be explicitly enabled or disabled (XamlCompilationOptions.Skip) at both the assembly and class level by adding the XamlCompilation attribute.
The following code example demonstrates enabling XAML compilation at the assembly level:
using Xamarin.Forms.Xaml;
...
[assembly: XamlCompilation (XamlCompilationOptions.Compile)]
namespace PhotoApp
{
...
}
While the attribute can be placed anywhere, a good place to put it is in AssemblyInfo.cs.
In this example, compile-time checking of all the XAML contained within the assembly will be performed, with XAML errors being reported at compile-time rather than run-time. Therefore, the assembly prefix to the XamlCompilation attribute specifies that the attribute applies to the entire assembly.
Note
The XamlCompilation attribute and the XamlCompilationOptions enumeration reside in the Xamarin.Forms.Xaml namespace, which must be imported to use them.
The following code example demonstrates enabling XAML compilation at the class level:
using Xamarin.Forms.Xaml;
...
[XamlCompilation (XamlCompilationOptions.Compile)]
public class HomePage : ContentPage
{
...
}
In this example, compile-time checking of the XAML for the HomePage class will be performed and errors reported as part of the compilation process.
Note
Compiled bindings can be enabled to improve data binding performance in Xamarin.Forms applications. For more information, see Compiled Bindings.