Implement counters for wrong and right answers

[mgolokhov]

We use ViewPager with Fragments, so when current View is changed other (cached) Views should be notified.

Possible solutions:

• to turn off pre-rendering setOffscreenPageLimit(int) not good.
• implement observer interface and notify all cached Views

Also counters should be moved to the global scope.

[mgolokhov]

green - right counter, red - wrong counter

Commit can be used as a trigger for notification, in that case it should be moved to the activity

[mgolokhov]

You can't set setOffscreenPageLimit(int) less than DEFAULT_OFFSCREEN_PAGES and DEFAULT_OFFSCREEN_PAGES = 1

[mgolokhov]

Temporary solution (every view will be recreated): @Override public int getItemPosition(Object object) { return POSITION_NONE; }