string has value converter

src/App/Utilities/StringHasValueConverter.cs

@@ -0,0 +1,24 @@
+using System;
+using Xamarin.Forms;
+
+namespace Bit.App.Utilities
+{
+    public class StringHasValueConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter,
+            System.Globalization.CultureInfo culture)
+        {
+            if(targetType == typeof(bool) && value.GetType() == typeof(string))
+            {
+                return !string.IsNullOrWhiteSpace((string)value);
+            }
+            throw new InvalidOperationException("The value must be a string with a boolean target.");
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter,
+            System.Globalization.CultureInfo culture)
+        {
+            throw new NotSupportedException();
+        }
+    }
+}