// Code to execute when the application is launching (eg, from Start)
// This code will not execute when the application is reactivated
private void Application_Launching(object sender, LaunchingEventArgs e)
{
//Create new data object variable
MainViewModel _mvm = new MainViewModel();
ObservableCollection<MainModel> items = null;
//Try to load previously saved data from IsolatedStorage
using (IsolatedStorageFile isf = IsolatedStorageFile.GetUserStoreForApplication())
{
//Check if file exits
if (isf.FileExists(STORAGE_FILE_NAME))
{
using (IsolatedStorageFileStream fs = isf.OpenFile(STORAGE_FILE_NAME, System.IO.FileMode.Open))
{
//Read the file contents and try to deserialize it back to data object
XmlSerializer ser = new XmlSerializer(typeof(ObservableCollection<MainModel>));
object obj = ser.Deserialize(fs);
//If successfully deserialized, initialize data object variable with it
if (null != obj && obj is ObservableCollection<MainModel>)
{
items = obj as ObservableCollection<MainModel>;
TwitterApplication.Util.Utils.Trace("Fant " + items.Count + " elementer");
}
else
{
items = new ObservableCollection<MainModel>();
TwitterApplication.Util.Utils.Trace("Fant ingen elementer");
}
}
}
else
{
//If previous data not found, create new istance
items = new ObservableCollection<MainModel>();
TwitterApplication.Util.Utils.Trace("Fant ikke fil");
}
}
_mvm.Items = items;
//Set data variable (either recovered or new) as a DataContext for all the pages of the application
RootFrame.DataContext = _mvm;
}
// Load data for the ViewModel Items
private void MainPage_Loaded(object sender, RoutedEventArgs e)
{
Mvm = (MainViewModel)DataContext;
}
// 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)
{
//Create new data object variable
MainViewModel _mvm = new MainViewModel();
ObservableCollection<MainModel> items = null;
//Try to locate previous data in transient state of the application
if (PhoneApplicationService.Current.State.ContainsKey(STATE_KEY))
{
//If found, initialize the data variable and remove in from application's state
items = PhoneApplicationService.Current.State[STATE_KEY] as ObservableCollection<MainModel>;
PhoneApplicationService.Current.State.Remove(STATE_KEY);
}
//If found set it as a DataContext for all the pages of the application
//An application is not guaranteed to be activated after it has been tombstoned,
//thus if not found create new data object
if (null != items)
_mvm.Items = items;
else
_mvm.Items = new ObservableCollection<MainModel>();
RootFrame.DataContext = _mvm;
}
