I have developed two simple components to show a title bar and, when a menu icon on the title bar is pressed, show a navigation menu. By far the most complex part of the development was managing the communication between components. After lots of testing and confusing results I realised that the issue was the undefined state of the Boolean variable used to switch the menu's visibility when the app is first loaded. Because there is no equivalent of OnStart or OnVisible for a component (and the component cannot share variables with the container app or screen, any logic depending on this variable needs to consider all three possible states. Because variables are often used to hold values within a component for output to the containing app or other components, the ability to initialise a variable on load of the app would be beneficial.