Storing Arraylist Of Points To A File In Java For Android

I am unable to write the ArrayList to a file. I am doing as following, what is the correct way? If I don't add 'pt' into arraylist, process goes fine and it gets saved. os.writeOb

Solution 1:

To seralize the List<Point>, your Point class must be serializable.

publicclassPointimplementsSerializable {...}

I'd suggest to use JSON (gson) API to read and write objects directly.

Solution 2:

Instead of keeping Points in ArrayList, you can add two Integers per point. Integer supports Serializable, Point does not.

Solution 3:

android.graphics.Point is not Serializable.

Make a new class PointSerializable which will copy android.graphics.Point in to custom Point class

classPointimplementsSerializable
{
    privatestaticfinallongserialVersionUID=1L;

    privateint x;
    privateint y;

    Point(android.graphics.Point point)
    {
        this.x  = point.x;
        this.y= point.y;
    }
}