diff --git a/Example/Example.csproj b/Example/Example.csproj
index d5d1b84..dfddd9e 100644
--- a/Example/Example.csproj
+++ b/Example/Example.csproj
@@ -70,6 +70,9 @@
     <Reference Include="PresentationFramework">
       <RequiredTargetFramework>3.0</RequiredTargetFramework>
     </Reference>
+    <Reference Include="WPF.MDI, Version=1.1.3.0, Culture=neutral, processorArchitecture=MSIL">
+      <HintPath>..\packages\WPF.MDI.1.1.3\lib\net40-client\WPF.MDI.dll</HintPath>
+    </Reference>
   </ItemGroup>
   <ItemGroup>
     <ApplicationDefinition Include="App.xaml">
@@ -108,12 +111,6 @@
     </Compile>
     <AppDesigner Include="Properties\" />
   </ItemGroup>
-  <ItemGroup>
-    <ProjectReference Include="..\WPF.MDI\WPF.MDI.csproj">
-      <Project>{BE1ED569-5E0B-4DF0-8964-33AD2AAE4C4A}</Project>
-      <Name>WPF.MDI</Name>
-    </ProjectReference>
-  </ItemGroup>
   <ItemGroup>
     <Resource Include="OriginalLogo.png" />
   </ItemGroup>
@@ -136,6 +133,7 @@
   </ItemGroup>
   <ItemGroup>
     <None Include="app.config" />
+    <None Include="packages.config" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
diff --git a/Example/packages.config b/Example/packages.config
new file mode 100644
index 0000000..0feb332
--- /dev/null
+++ b/Example/packages.config
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="WPF.MDI" version="1.1.3" targetFramework="net40-client" />
+</packages>
\ No newline at end of file
diff --git a/WPF.MDI/MdiContainer.cs b/WPF.MDI/MdiContainer.cs
index f022072..f2122b3 100644
--- a/WPF.MDI/MdiContainer.cs
+++ b/WPF.MDI/MdiContainer.cs
@@ -338,9 +338,9 @@ private void Children_CollectionChanged(object sender, NotifyCollectionChangedEv
 						MdiChild mdiChild = Children[e.NewStartingIndex],
 							topChild = ActiveMdiChild;
 
+						mdiChild.Loaded += (s, a) => ActiveMdiChild = mdiChild;
 						if (topChild != null && topChild.WindowState == WindowState.Maximized)
 							mdiChild.Loaded += (s, a) => mdiChild.WindowState = WindowState.Maximized;
-						mdiChild.Loaded += (s, a) => ActiveMdiChild = mdiChild;
 
 						if (mdiChild.Position.X < 0 || mdiChild.Position.Y < 0)
 							mdiChild.Position = new Point(_windowOffset, _windowOffset);
diff --git a/WPF.MDI/Properties/AssemblyInfo.cs b/WPF.MDI/Properties/AssemblyInfo.cs
index 2696797..086eada 100644
--- a/WPF.MDI/Properties/AssemblyInfo.cs
+++ b/WPF.MDI/Properties/AssemblyInfo.cs
@@ -8,11 +8,11 @@
 // set of attributes. Change these attribute values to modify the information
 // associated with an assembly.
 [assembly: AssemblyTitle("WPF.MDI")]
-[assembly: AssemblyDescription("http://wpfmdi.codeplex.com/")]
+[assembly: AssemblyDescription("A library to add the traditional Windows Forms Multiple Document Interface (MDI) features to WPF. The aim is to resemble the original as much as possible.")]
 [assembly: AssemblyConfiguration("")]
-[assembly: AssemblyCompany("xadet")]
+[assembly: AssemblyCompany("xadet,flames")]
 [assembly: AssemblyProduct("WPF.MDI")]
-[assembly: AssemblyCopyright("2009 xadet, 2010 stbear")]
+[assembly: AssemblyCopyright("2009 xadet, 2010 stbear, 2021 flames")]
 [assembly: AssemblyTrademark("")]
 [assembly: AssemblyCulture("")]
 
@@ -25,5 +25,5 @@
     //(used if a resource is not found in the page, 
     // app, or any theme specific resource dictionaries)
 )]
-[assembly: AssemblyVersion("1.1.1.0")]
-[assembly: AssemblyFileVersion("1.1.1.0")]
+[assembly: AssemblyVersion("1.1.4.0")]
+[assembly: AssemblyFileVersion("1.1.4.0")]
diff --git a/WPF.MDI/WPF.MDI.nuspec b/WPF.MDI/WPF.MDI.nuspec
new file mode 100644
index 0000000..7f34fcf
--- /dev/null
+++ b/WPF.MDI/WPF.MDI.nuspec
@@ -0,0 +1,48 @@
+<?xml version="1.0" encoding="utf-8"?>
+<package >
+  <metadata>
+    <!-- Identifier that must be unique within the hosting gallery -->
+    <id>$id$</id>
+
+    <!-- Package version number that is used when resolving dependencies -->
+    <version>$version$</version>
+    
+    <title>$title$</title>
+
+    <!-- Authors contain text that appears directly on the gallery -->
+    <authors>$author$</authors>
+
+    <!-- If true, this value prompts the user to accept the license when installing the package.  -->
+    <requireLicenseAcceptance>false</requireLicenseAcceptance>
+
+    <!-- License information is displayed on the gallery -->
+    <license type="expression">MIT</license>
+
+    <!-- Project URL provides a link for the gallery -->
+    <projectUrl>https://github.com/flamegreat/wpfmdi.git</projectUrl>
+
+    <!-- Icon is used in Visual Studio's package manager UI -->
+    <icon>images\icon.png</icon>
+    
+    <!-- The description can be used in package manager UI. Note that the nuget.org gallery uses information you add in the portal. -->
+    <description>$description$</description>
+    <releaseNotes>代码相较之前的版本没有任何变化，只是更新一些Nuget包信息。</releaseNotes>
+
+    <!-- Copyright information -->
+    <copyright>$copyright$</copyright>
+
+    <!-- Tags appear in the gallery and can be used for tag searches -->
+    <tags>WPF MDI</tags>
+
+    <!-- Dependencies are automatically installed when the package is installed -->
+    <dependencies>
+      <group targetFramework=".NETFramework4.0-Client" />
+    </dependencies>
+  </metadata>
+
+  <!-- A readme.txt to display when the package is installed -->
+  <files>
+    <file src="icon.png" target="images\" />
+  </files>
+  
+</package>
\ No newline at end of file
diff --git a/WPF.MDI/icon.png b/WPF.MDI/icon.png
new file mode 100644
index 0000000..fe4a267
Binary files /dev/null and b/WPF.MDI/icon.png differ