Async loading item images => huge performance improvements for old machines.

Wox/Converters/AsyncConverter.cs

@@ -0,0 +1,38 @@
+using System;
+using System.ComponentModel;
+using System.Threading;
+using System.Windows.Data;
+using System.Windows.Threading;
+
+namespace Wox.Converters
+{
+    public class AsyncTask : INotifyPropertyChanged
+    {
+        public AsyncTask(Func<object> valueFunc)
+        {
+            LoadValue(valueFunc);
+        }
+
+        private void LoadValue(Func<object> valueFunc)
+        {
+            var frame = new DispatcherFrame();
+            ThreadPool.QueueUserWorkItem(delegate
+            {
+            
+                        object returnValue =
+                        AsyncValue = valueFunc();
+                        if (PropertyChanged != null)
+                            PropertyChanged(this, new PropertyChangedEventArgs("AsyncValue"));
+                
+            });
+        }
+
+        public event PropertyChangedEventHandler PropertyChanged;
+
+        public object AsyncValue
+        {
+            get;
+            set;
+        }
+    }
+}

Wox/Converters/ImagePathConverter.cs

@@ -1,30 +1,32 @@
 using System;
+using System.Diagnostics;
 using System.Globalization;
 using System.IO;
+using System.Windows;
 using System.Windows.Data;
 using System.Windows.Media.Imaging;
 using Wox.Helper;
 
 namespace Wox.Converters
 {
-    public class ImagePathConverter : IMultiValueConverter
+    public class ImagePathConverter : IValueConverter
     {
-        public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
         {
-            if (values[0] == null) return null;
+            if (value == null || value == DependencyProperty.UnsetValue) return null;
 
-            string relativePath = values[0].ToString();
-            string pluginDirectory = values[1].ToString();
-            string fullPath = Path.Combine(pluginDirectory, relativePath);
+            string fullPath = value.ToString();
 
-            if (relativePath.StartsWith("data:", StringComparison.OrdinalIgnoreCase))
+            if (fullPath.StartsWith("data:", StringComparison.OrdinalIgnoreCase))
             {
-                return new BitmapImage(new Uri(relativePath));
+                return new BitmapImage(new Uri(fullPath));
             }
+
+            
             return ImageLoader.Load(fullPath);
         }
 
-        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture)
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
         {
             return null;
         }