Storing HashMap in Internal Storage error

Question

I have a Hashmap in a Fragment variable for a Position(int) to View Relationship. sometimes I can read the Object in onCreate but with no data ( size 0) , However when I want to store it when onPause or onStop fires of the fragment to internal storage , it gives me a weird error without any clue what cause it:

android.widget.RelativeLayout

Fragment onPause:

@Override
protected void onPause() {
    super.onPause();
    try
    {
        FileOutputStream fileOutStream = getContext().openFileOutput("hashMap", Context.MODE_PRIVATE);
        ObjectOutputStream objOutStream = new ObjectOutputStream(fileOutStream);
        objOutStream.writeObject(HashMap);
        objOutStream.close();
        Log.v("Fragment:", "Done Writing "+HashMap.size());
    }catch (IOException e)
    {
        Log.v("Fragment:","MainPage(onStop): "+e.getMessage()+e.getLocalizedMessage());
    }
}

the following lines to read from internal storage when opening the app.

try {
        FileInputStream f = getContext().openFileInput("hashMap");
        ObjectInputStream s = new ObjectInputStream(f);
        HashMap= (HashMap<Integer, View>) s.readObject();
        s.close();
        Log.v("Fragment:", "Done Reading " + HashMap.size());
    } catch (ClassNotFoundException | IOException e) {
        Log.v("Fragment:", "MainPage(onCreate): " + e.getMessage());
    }

It looks like you're trying to save Views and read them back in which case you can't do this nor would you ever want to. Views don't inherit from the `Seriablizable` interface. Save the **state** of the View (i.e. the data the View is displaying), and rebuild it when coming back. — DeeV, Jan 18 '16 at 15:54

score 1 · Answer 1 · answered Jan 18 '16 at 15:55

1

I think

Only objects that support the java.io.Serializable interface can be written to streams according to ObjectOutputStream

The View does not seem to implement this interface.

answered Jan 18 '16 at 15:55

Radu Ionescu

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my Fragment class : public class MainPage extends Fragment implements java.io.Serializable(...) – Flava Jan 18 '16 at 16:02
But the HashMap is of Views and to deal with non-serializable fields you need something like this [Serialization with non serilazable parts](http://stackoverflow.com/questions/95181/java-serialization-with-non-serializable-parts) – Radu Ionescu Jan 18 '16 at 16:06

Storing HashMap in Internal Storage error

1 Answers1