Thank you for writing.
The source code for the example that can be seen in your second attachment is available in the the demo application. Just switch to the tab with the preferred programming language.
This example also uses custom visual items. Information about how such items can be created is available in the following help article: Custom items
If you need additional styling you can check the following article which describes the items formatting: Formatting Items
Do not hesitate to contact us if you have other questions.