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c#windows-phone-8coordinatestombstoning

How to save a coordinate list after app is tombstoned?


I have a list of coordinates saved in a map class that are manipulated to draw a route between the points, but I'm not sure how to save these points when the application is closed and then reopened.

This is how I currently save the points within the app in the OnNavigatedTo(), the points and markers aren't lost as long as I don't close it. But how do I save these coordinates after I close the app?

I'm guessing I should save them in the OnNavigatedFrom but I tried saving the coordinate list here and the markers don't show when I repopen the app.

//save the coordinates to a list
mycoord.Add(new GeoCoordinate(MyGeoPosition.Latitude, MyGeoPosition.Longitude));

if (mycoord.Count == 2)
{
  //call route method when coord list equal to two.
  GetRoute();
}

Solution

  • The easiest way to do this that is customizable would be to create a custom object and serialize it to the phone's storage using EZ_Iso.dll

    Here's an example

    //Your custom GeoCoord container
    [DataContractAttribute]
    public class GeoCoordContainer{
      [DataMember]
      public double lat = 0;
    
      [DataMember]
      public double lon = 0;
    
      public GeoCoordContainer(Double lat, Double lon){
        this.lat = lat;
        this.lon = lon;
      }
    }
    
    
    //Then in your Navigated from method
      GeoCoordContainer cont = new GeoCoordContainer(MyGeoPosition.Lattitude,MyGeoPosition.Longitued);
    
      //Now save it to the storage using EZ_Iso
      EZ_Iso.IsolatedStorageAccess.SaveFile("MyLocation",cont);
    
    
     //To Retrieve it from storage 
      GeoCoordContainer cont = (GeoCoordContainer)EZ_Iso.IsolatedStorageAccess.GetFile("MyLocation",typeof(GeoCoordContainer));
    

    You can find EZ_Iso.dll free here http://anthonyrussell.info/postpage.php?name=2