Tip: Consume Cursor as RxJava2 Iterable

This is going to be really short tip how to iterate over Cursor using RxJava. I promise!

In RxJava, we can emit items from Iterable as Observable.fromArray(). Cursor is structure that can be iterated, given his methods, but it does not implement Iterator.

IteratingCursor with Observablewill grant you opportunities to perform additional operation on the Cursor data in the same call/thread/task.

For emitting items, in this case, moving internal position pointer of the Cursor forwards, we need to create Iterable that will do it:

1. We need to move the Cursor when Iterator hasNext() has been called.
2. Be careful, always check for Cursor not being closed.
3. Close the cursor, if you don’t need it anymore. (optional but recommended)

Example usage:

Observable.fromIterable(RxCursorIterable.from(cursor))....doAfterNext(new Consumer<Cursor>() {
    @Override
    public void accept(Cursor cursor) throws Exception {
        if (cursor.getPosition() == cursor.getCount() - 1) {
            cursor.close();
        }
    }
}).subscribe(new Consumer<Cursor>() {
    @Override
    public void accept(Cursor cursor) throws Exception {
        //Do something. Cursor has been moved +1 position forward.    }
});

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