Intellisense is something nice but might behave strange sometimes and deliver errors in its list of possibilities
When your intellisense worked but looks outdated since you changed UI components. e.g. the new added components or renamed onces are not there but the old names can be seen. In this case it helps to rename or delete (I always rename) the *.ncb file in your project. This file will be regenerated automatically. I do a clean and build afterwards. Now you will see your newly added ui components when using intellisense.
About the Author
Wim Peeters is electronics engineer with an additional master in IT and over 30 years of experience including time spent in support, development, consulting, training and database administration. Wim has worked with SQL Server since version 6.5. He has developed in C/C++, Java and C# on Windows and Linux in different European countries and different European languages. He writes knowledge base articles to solve IT problems and publishes them on the Lubby Knowledge Platform where he is one of the most important contributors and the main developer.