Create custom view for counter

- [ ] Create custom view
- [ ] Add custom attributes for state of view (state should be called `state_readed` and type is boolean)
- [ ] Add custom attributes for view (`readed_color` and `unreaded_color`)
- [ ] If the state has been changed, change the background color to one of color `readed_color` or `unreaded_color`
- [ ] Custom view should only accept int value

Helpful links:
* [Custom state of view](https://stackoverflow.com/questions/4336060/how-to-add-a-custom-button-state)