Recover TinyDB saves with Java and Android Studio

[Andrea Barcaro]

Hi at all,

I'm trying to update my application previously made with App Inventor. In that application I used the TinyDB component.

Now the app is written in Java with Android Studio and I used again TinyDB from this github (https://github.com/kcochibili/TinyDB--Android-Shared-Preferences-Turbo/blob/master/TinyDB.java). I can save and delete savedata successfully.

What I'd like to do is recover my savefiles from the App Inventor TinyDB. The problem is that with App Inventor I saved this:

tag: "actualSavefiles"

valueToStore: make a list(list of double, list of double, list of String)

How can I recover this TinyDB with Java TinyDB?

The problem is that I don't know what is the the class of a list stored with App Inventor and containing a list of double, a list of double and a list of String.

I mean, in Java an ArrayList of string object is List<String>. 

With SharedPreferences I can get the saves but I can't find what is that class (and from there I could know how to export double and string values).

Thanks for the attention,

Andrea

[Ghica]

If you still have the AI source code, maybe you make a new version that exports the TinyDB as one or more CSV files. You could then import that CSV file to your new Java app.

Cheers, Ghica.

[Jos Flores]

I had never seen that TinyDB implementation. You will probably have to
ask the owner of the github repo how to use it.
It seems to be a very similar implementation to the one in App
Inventor, but no idea if it is supposed to be compatible.

The AI component stores Objects, using a couple of JSON util methods.
Here's where/what it returns:
https://github.com/mit-cml/appinventor-sources/blob/master/appinventor/components/src/com/google/appinventor/components/runtime/TinyDB.java#L115

and here is the JSON util method used:
https://github.com/mit-cml/appinventor-sources/blob/master/appinventor/components/src/com/google/appinventor/components/runtime/util/JsonUtil.java#L194

You may be able to figure out what's returning by following the links above.

cheers,
José

> --
> You received this message because you are subscribed to the Google Groups
> "App Inventor Open Source Development" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to app-inventor-open-so...@googlegroups.com.
> To post to this group, send email to
> app-inventor-o...@googlegroups.com.
> Visit this group at
> https://groups.google.com/group/app-inventor-open-source-dev.
> For more options, visit https://groups.google.com/d/optout.

[Andrea Barcaro]

thanks to all for reply.

First of all I imported "kawa-2.0.jar" and from the source of App Inventor: ArrayIndexOutOfBoundsError.java, IllegalArgumentError.java, JsonUtil.java, Lists.java, RuntimeError.java, UninitializedInstanceError.java, YailConstants.java, YailList.java, YailNumberToString.java, YailRuntimeError.java.

Then I modified the TinyDB.java from the git in this part:

public TinyDB(Context appContext) {
    //Before it was preferences = PreferenceManager.getDefaultSharedPreferences(appContext);

    //In this way with "TinyDB1" the place where tags are saved is the same with the one used in App Inventor
    preferences=appContext.getApplicationContext().getSharedPreferences("TinyDB1", Context.MODE_PRIVATE);
}

and I paste in this TinyDB.java this code:

public Object GetValue(final String tag, final Object valueIfTagNotThere) {
    try {
        String value = preferences.getString(tag, "");
        // If there's no entry with tag as a key then return the empty string.
        //    was  return (value.length() == 0) ? "" : JsonUtil.getObjectFromJson(value);
        return (value.length() == 0) ? valueIfTagNotThere : JsonUtil.getObjectFromJson(value);
    } catch (JSONException e) {
        throw new YailRuntimeError("Value failed to convert from JSON.", "JSON Creation Error.");
    }
}

Then in my app I did:

//Initialize the variables

List<String> listone;
List<String> listtwo;
List<Double> listthree;
Object save;

//Get the saves

tinydb=new TinyDB(this);

save = tinydb.GetValue("actualSavefiles","");

//Create now the ArrayList containing the savefiles

ArrayList al1 = (ArrayList) save;

//Put your App Inventor saves in your variables
listone=(ArrayList)al1.get(0);
listtwo=(ArrayList)al1.get(1);
listthree=(ArrayList) al1.get(2);

Hope that this could be useful to someone
thanks for the inputs;)