From a25a7fb3fd81b5817e514b71c3aab7e22204deea Mon Sep 17 00:00:00 2001
From: Claudiu Farcas <farcas.claudiu@gmail.com>
Date: Fri, 25 Mar 2011 13:47:13 +0200
Subject: [PATCH] tombstoning - saving and loadign from IsolateStorage

---
 main/MyFriendsAround.WP7/App.xaml.cs          | 38 ++++++++++
 .../MyFriendsAround.WP7.csproj                |  1 +
 .../Utils/ApplicationExtensions.cs            | 60 ++++++++++++++++
 .../ViewModel/MainViewModel.cs                | 26 ++++++-
 .../ViewModel/ViewModelLocator.cs             | 14 ++--
 main/MyFriendsAround.WP7/Views/MainPage.xaml  | 72 +++++++++++--------
 6 files changed, 173 insertions(+), 38 deletions(-)
 create mode 100644 main/MyFriendsAround.WP7/Utils/ApplicationExtensions.cs

diff --git a/main/MyFriendsAround.WP7/App.xaml.cs b/main/MyFriendsAround.WP7/App.xaml.cs
index ff61a3e..97e1652 100644
--- a/main/MyFriendsAround.WP7/App.xaml.cs
+++ b/main/MyFriendsAround.WP7/App.xaml.cs
@@ -13,6 +13,8 @@ using System.Windows.Shapes;
 using Microsoft.Phone.Controls;
 using Microsoft.Phone.Shell;
 using MyFriendsAround.WP7.ViewModel;
+using MyFriendsAround.WP7.Utils;
+
 
 namespace MyFriendsAround.WP7
 {
@@ -43,28 +45,63 @@ namespace MyFriendsAround.WP7
         // This code will not execute when the application is reactivated
         private void Application_Launching(object sender, LaunchingEventArgs e)
         {
+            LoadModel();
         }
 
         // Code to execute when the application is activated (brought to foreground)
         // This code will not execute when the application is first launched
         private void Application_Activated(object sender, ActivatedEventArgs e)
         {
+            LoadModel();
         }
 
         // Code to execute when the application is deactivated (sent to background)
         // This code will not execute when the application is closing
         private void Application_Deactivated(object sender, DeactivatedEventArgs e)
         {
+            SaveModel();
         }
 
         // Code to execute when the application is closing (eg, user hit Back)
         // This code will not execute when the application is deactivated
         private void Application_Closing(object sender, ClosingEventArgs e)
         {
+            SaveModel();
+            //
             ViewModelLocator locator = Container.Instance.Resolve<ViewModelLocator>();
             locator.Cleanup();
         }
 
+
+        private void LoadModel()
+        {
+            MainViewModel mainModel = this.RetrieveFromIsolatedStorage<MainViewModel>();
+            if (mainModel != null)
+            {
+                Container.Instance.RegisterInstance<MainViewModel>(mainModel, "MainViewModel");
+            }
+            else
+            {
+                Container.Instance.RegisterInstance<MainViewModel>(new MainViewModel(), "MainViewModel");
+            }
+            AboutViewModel aboutModel = this.RetrieveFromIsolatedStorage<AboutViewModel>();
+            if (aboutModel != null)
+            {
+                Container.Instance.RegisterInstance<AboutViewModel>(aboutModel, "AboutViewModel");
+            }
+            else
+            {
+                Container.Instance.RegisterInstance<AboutViewModel>( new AboutViewModel(), "AboutViewModel");
+            }
+        }
+
+        private void SaveModel()
+        {
+            this.SaveToIsolatedStorage<MainViewModel>(Container.Instance.Resolve<MainViewModel>("MainViewModel"));
+            this.SaveToIsolatedStorage<AboutViewModel>(Container.Instance.Resolve<AboutViewModel>("AboutViewModel"));
+        }
+
+
         // Code to execute if a navigation fails
         void RootFrame_NavigationFailed(object sender, NavigationFailedEventArgs e)
         {
@@ -85,6 +122,7 @@ namespace MyFriendsAround.WP7
             }
         }
 
+
         #region Phone application initialization
 
         // Avoid double-initialization
diff --git a/main/MyFriendsAround.WP7/MyFriendsAround.WP7.csproj b/main/MyFriendsAround.WP7/MyFriendsAround.WP7.csproj
index 59c6ecb..aff3d71 100644
--- a/main/MyFriendsAround.WP7/MyFriendsAround.WP7.csproj
+++ b/main/MyFriendsAround.WP7/MyFriendsAround.WP7.csproj
@@ -118,6 +118,7 @@
     </Compile>
     <Compile Include="Helpers\Navigation\IPageNavigation.cs" />
     <Compile Include="Helpers\Navigation\PageNavigation.cs" />
+    <Compile Include="Utils\ApplicationExtensions.cs" />
     <Compile Include="Views\AboutPage.xaml.cs">
       <DependentUpon>AboutPage.xaml</DependentUpon>
     </Compile>
diff --git a/main/MyFriendsAround.WP7/Utils/ApplicationExtensions.cs b/main/MyFriendsAround.WP7/Utils/ApplicationExtensions.cs
new file mode 100644
index 0000000..062b161
--- /dev/null
+++ b/main/MyFriendsAround.WP7/Utils/ApplicationExtensions.cs
@@ -0,0 +1,60 @@
+using System;
+using System.Net;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Documents;
+using System.Windows.Ink;
+using System.Windows.Input;
+using System.Windows.Media;
+using System.Windows.Media.Animation;
+using System.Windows.Shapes;
+using System.IO.IsolatedStorage;
+using System.IO;
+using MyFriendsAround.WP7.ViewModel;
+using System.Text;
+
+namespace MyFriendsAround.WP7.Utils
+{
+    public static class ApplicationExtensions
+    {
+
+        private static string GetIsFile(Type t)
+        {
+            return string.Concat(t.Name, ".dat");
+        }
+
+
+        public static T RetrieveFromIsolatedStorage<T>(this Application app) where T : class
+        {
+            using (var userAppStore = IsolatedStorageFile.GetUserStoreForApplication())
+            {
+                var dataFileName = GetIsFile(typeof(T));
+                if (userAppStore.FileExists(dataFileName))
+                {
+                    using(StreamReader sr =new StreamReader(userAppStore.OpenFile(dataFileName, FileMode.Open), Encoding.UTF8))
+                    {
+                        return SerializationHelper.Deserialize<T>(sr.ReadToEnd());    
+                    }
+                }
+            }
+            return null;
+        }
+
+        public static void SaveToIsolatedStorage<T>(this Application app, T model) where T : class
+        {
+            var dataFileName = GetIsFile((model.GetType()));
+            using (var userAppStore = IsolatedStorageFile.GetUserStoreForApplication())
+            {
+                if (userAppStore.FileExists(dataFileName))
+                {
+                    userAppStore.DeleteFile(dataFileName);
+                }
+                using (StreamWriter sw = new StreamWriter(userAppStore.CreateFile(dataFileName), Encoding.UTF8))
+                {
+                    sw.Write(SerializationHelper.Serialize<T>(model));
+                }
+            }
+        }
+
+    }
+}
diff --git a/main/MyFriendsAround.WP7/ViewModel/MainViewModel.cs b/main/MyFriendsAround.WP7/ViewModel/MainViewModel.cs
index 5329081..01298c6 100644
--- a/main/MyFriendsAround.WP7/ViewModel/MainViewModel.cs
+++ b/main/MyFriendsAround.WP7/ViewModel/MainViewModel.cs
@@ -171,7 +171,31 @@ namespace MyFriendsAround.WP7.ViewModel
         }
 
 
-        public string MyName { get; set; }
+        /// <summary>
+        /// The <see cref="MyName" /> property's name.
+        /// </summary>
+        public const string MyNamePropertyName = "MyName";
+        private string _myName = "Guest";
+
+        /// <summary>
+        /// Gets the MyName property.
+        /// </summary>
+        public string MyName
+        {
+            get { return _myName; }
+            set
+            {
+                if (_myName == value)
+                {
+                    return;
+                }
+                var oldValue = _myName;
+                _myName = value;
+                // Update bindings, no broadcast
+                RaisePropertyChanged(MyNamePropertyName);
+            }
+        }
+
 
         public string AppBarTextAbout {
             get { return "About"; }
diff --git a/main/MyFriendsAround.WP7/ViewModel/ViewModelLocator.cs b/main/MyFriendsAround.WP7/ViewModel/ViewModelLocator.cs
index 132d4f0..c411286 100644
--- a/main/MyFriendsAround.WP7/ViewModel/ViewModelLocator.cs
+++ b/main/MyFriendsAround.WP7/ViewModel/ViewModelLocator.cs
@@ -74,8 +74,6 @@ namespace MyFriendsAround.WP7.ViewModel
                 // Create run time view models
             }
 
-            Container.Instance.RegisterInstance(typeof(MainViewModel), "MainViewModel");
-            Container.Instance.RegisterInstance(typeof(AboutViewModel), "AboutViewModel");
         }
 
         /// <summary>
@@ -85,7 +83,7 @@ namespace MyFriendsAround.WP7.ViewModel
         {
             get
             {
-                MainViewModel mainViewModel = GetViewModel<MainViewModel>();
+                MainViewModel mainViewModel = GetViewModel<MainViewModel>("MainViewModel");
                 return mainViewModel;
             }
         }
@@ -97,7 +95,7 @@ namespace MyFriendsAround.WP7.ViewModel
         {
             get
             {
-                AboutViewModel aboutViewModel = GetViewModel<AboutViewModel>();
+                AboutViewModel aboutViewModel = GetViewModel<AboutViewModel>("AboutViewModel");
                 return aboutViewModel;
             }
         }
@@ -108,9 +106,9 @@ namespace MyFriendsAround.WP7.ViewModel
         /// </summary>
         public void Cleanup()
         {
-            MainViewModel mainViewModel = GetViewModel<MainViewModel>();
+            MainViewModel mainViewModel = GetViewModel<MainViewModel>("MainViewModel");
             mainViewModel.Cleanup();
-            AboutViewModel aboutViewModel = GetViewModel<AboutViewModel>();
+            AboutViewModel aboutViewModel = GetViewModel<AboutViewModel>("AboutViewModel");
             aboutViewModel.Cleanup();
         }
 
@@ -118,10 +116,10 @@ namespace MyFriendsAround.WP7.ViewModel
 
         #region Local Helpers
 
-        private T GetViewModel<T>() where T : ViewModelBase
+        private T GetViewModel<T>(string key) where T : ViewModelBase
         {
             // Create a new view model
-            T vm = Container.Instance.Resolve<T>();
+            T vm = Container.Instance.Resolve<T>(key);
 
             //Assign the Context from PageNavigation to Context property of the ViewModelBase
             vm.Context = vm.PageNav.CurrentContext;
diff --git a/main/MyFriendsAround.WP7/Views/MainPage.xaml b/main/MyFriendsAround.WP7/Views/MainPage.xaml
index 7856dc7..5b6dbb6 100644
--- a/main/MyFriendsAround.WP7/Views/MainPage.xaml
+++ b/main/MyFriendsAround.WP7/Views/MainPage.xaml
@@ -1,10 +1,14 @@
-<phone:PhoneApplicationPage xmlns:toolkit="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit"  x:Class="MyFriendsAround.WP7.MainPage"
+<phone:PhoneApplicationPage xmlns:toolkit="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit"
+                            x:Class="MyFriendsAround.WP7.MainPage"
                             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                             xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
                             xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
                             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
-                            xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity" xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Extras.WP7" FontFamily="{StaticResource PhoneFontFamilyNormal}"
+                            xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+                            xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
+                            xmlns:cmd="clr-namespace:GalaSoft.MvvmLight.Command;assembly=GalaSoft.MvvmLight.Extras.WP7"
+                            FontFamily="{StaticResource PhoneFontFamilyNormal}"
                             FontSize="{StaticResource PhoneFontSizeNormal}"
                             Foreground="{StaticResource PhoneForegroundBrush}"
                             SupportedOrientations="Portrait"
@@ -14,15 +18,17 @@
                             d:DesignHeight="768"
                             shell:SystemTray.IsVisible="True"
                             DataContext="{Binding Main, Source={StaticResource Locator}}"
-                            xmlns:my="clr-namespace:Microsoft.Phone.Controls.Maps;assembly=Microsoft.Phone.Controls.Maps" xmlns:Preview="clr-namespace:Phone7.Fx.Preview;assembly=Phone7.Fx.Preview">
+                            xmlns:my="clr-namespace:Microsoft.Phone.Controls.Maps;assembly=Microsoft.Phone.Controls.Maps"
+                            xmlns:Preview="clr-namespace:Phone7.Fx.Preview;assembly=Phone7.Fx.Preview">
 
-	<!--LayoutRoot contains the root grid where all other page content is placed-->
+    <!--LayoutRoot contains the root grid where all other page content is placed-->
 
     <phone:PhoneApplicationPage.Resources>
         <ControlTemplate x:Key="PushpinControlTemplate1"
                          TargetType="my:Pushpin">
             <Grid Height="32"
-                  Width="32" Margin="-16,-16,0,0">
+                  Width="32"
+                  Margin="-16,-16,0,0">
                 <Ellipse Fill="#FFA3A3BE"
                          Stroke="Black"
                          Margin="0" />
@@ -32,25 +38,28 @@
     </phone:PhoneApplicationPage.Resources>
 
     <Grid x:Name="LayoutRoot"
-	      Background="Transparent">
-		<Grid.RowDefinitions>
-			<RowDefinition Height="Auto" />
-			<RowDefinition Height="*" />
-		</Grid.RowDefinitions>
+          Background="Transparent">
+        <Grid.RowDefinitions>
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="*" />
+        </Grid.RowDefinitions>
 
-		<!--TitlePanel contains the name of the application and page title-->
-		<StackPanel x:Name="TitlePanel"
-		            Grid.Row="0"
-		            Margin="24,24,0,12">
-			<TextBlock x:Name="ApplicationTitle"
-			           Text="{Binding ApplicationTitle}"
-			           Style="{StaticResource PhoneTextNormalStyle}" />
-            <TextBlock x:Name="PageTitle" Text="{Binding PageName}" Margin="-3,-8,0,0" Style="{StaticResource PhoneTextTitle1Style}" />
+        <!--TitlePanel contains the name of the application and page title-->
+        <StackPanel x:Name="TitlePanel"
+                    Grid.Row="0"
+                    Margin="24,24,0,12">
+            <TextBlock x:Name="ApplicationTitle"
+                       Text="{Binding ApplicationTitle}"
+                       Style="{StaticResource PhoneTextNormalStyle}" />
+            <TextBlock x:Name="PageTitle"
+                       Text="{Binding PageName}"
+                       Margin="-3,-8,0,0"
+                       Style="{StaticResource PhoneTextTitle1Style}" />
         </StackPanel>
 
-		<!--ContentPanel - place additional content here-->
-		<Grid x:Name="ContentGrid"
-		      Grid.Row="1"
+        <!--ContentPanel - place additional content here-->
+        <Grid x:Name="ContentGrid"
+              Grid.Row="1"
               Margin="0,0,0,70">
 
             <!--<Button Content="Publish"
@@ -65,7 +74,13 @@
                 </i:Interaction.Triggers>
             </Button>-->
 
-            <TextBox Height="67" HorizontalAlignment="Left" Margin="6,0,0,6" Name="txtMyName" Text="{Binding Path=MyName, Mode=TwoWay}" VerticalAlignment="Bottom" Width="468" />
+            <TextBox Height="67"
+                     HorizontalAlignment="Left"
+                     Margin="6,0,0,6"
+                     Name="txtMyName"
+                     Text="{Binding Path=MyName, Mode=TwoWay}"
+                     VerticalAlignment="Bottom"
+                     Width="468" />
             <my:Map x:Name="map"
                     Height="468"
                     HorizontalAlignment="Left"
@@ -73,12 +88,11 @@
                     VerticalAlignment="Top"
                     Width="468"
                     Center="{Binding Path=MapCenter, Mode=TwoWay}">
-                <my:MapItemsControl ItemsSource="{Binding PushPins}"
-                                    >
+                <my:MapItemsControl ItemsSource="{Binding PushPins}">
                     <my:MapItemsControl.ItemTemplate>
                         <DataTemplate>
                             <my:Pushpin Location="{Binding Location}"
-                                          Template="{StaticResource PushpinControlTemplate1}">
+                                        Template="{StaticResource PushpinControlTemplate1}">
                             </my:Pushpin>
                         </DataTemplate>
                     </my:MapItemsControl.ItemTemplate>
@@ -102,15 +116,15 @@
             <Preview:BindableApplicationBarIconButton Command="{Binding NavigateToAboutCommand}"
                                                       IconUri="/icons/appbar.questionmark.rest.png"
                                                       Text="{Binding AppBarTextAbout}" />
-            
+
             <Preview:BindableApplicationBar.MenuItems>
                 <Preview:BindableApplicationBarMenuItem  Text="Settings"
                                                          Command="{Binding InputBoxCommand}" />
             </Preview:BindableApplicationBar.MenuItems>
         </Preview:BindableApplicationBar>
     </Grid>
-    
-	<!-- Sample code showing usage of ApplicationBar
+
+    <!-- Sample code showing usage of ApplicationBar
     <phone:PhoneApplicationPage.ApplicationBar>
         <shell:ApplicationBar IsVisible="True" IsMenuEnabled="True">
             <shell:ApplicationBarIconButton x:Name="appbar_button1" IconUri="/Images/appbar_button1.png" Text="Button 1"></shell:ApplicationBarIconButton>
@@ -123,6 +137,6 @@
     </phone:PhoneApplicationPage.ApplicationBar>
     -->
 
-    
+
 
 </phone:PhoneApplicationPage>
\ No newline at end of file