PortablePrism.Portable by Andrii Chebukin

<PackageReference Include="PortablePrism.Portable" Version="1.0.1" />

 DelegateCommand<T>

An ICommand whose delegates can be attached for Execute and CanExecute. It also implements the IActiveAware interface, which is useful when registering this command in a CompositeCommand that monitors command's activity.
public DelegateCommand(Action<T> executeMethod)

Initializes a new instance of DelegateCommand<T>.

public DelegateCommand(Action<T> executeMethod, Func<T, bool> canExecuteMethod)

Initializes a new instance of DelegateCommand<T>.

public bool CanExecute(T parameter)

Determines if the command can execute by invoked the Func<T, U> provided during construction.

public void Execute(T parameter)

Executes the command and invokes the Action<T> provided during construction.