Catalog Lite

CatalogLite/AsyncCommand.cs

@@ -0,0 +1,42 @@
+using System.Windows.Input;
+
+namespace CatalogLite;
+
+public sealed class AsyncCommand : ICommand
+{
+    private readonly Func<Task> _execute;
+    private readonly Func<bool>? _canExecute;
+    private bool _isExecuting;
+
+    public AsyncCommand(Func<Task> execute, Func<bool>? canExecute = null)
+    {
+        _execute = execute ?? throw new ArgumentNullException(nameof(execute));
+        _canExecute = canExecute;
+    }
+
+    public event EventHandler? CanExecuteChanged;
+
+    public bool CanExecute(object? parameter) => !_isExecuting && (_canExecute?.Invoke() ?? true);
+
+    public async void Execute(object? parameter)
+    {
+        if (!CanExecute(parameter))
+        {
+            return;
+        }
+
+        try
+        {
+            _isExecuting = true;
+            RaiseCanExecuteChanged();
+            await _execute().ConfigureAwait(false);
+        }
+        finally
+        {
+            _isExecuting = false;
+            RaiseCanExecuteChanged();
+        }
+    }
+
+    public void RaiseCanExecuteChanged() => CanExecuteChanged?.Invoke(this, EventArgs.Empty);
+}