Delay render till visible
If enabled, delays rendering the List control until it is visible on the screen.
The Delay render till visible property controls whether or not the layout for the List control should be generated immediately when the app is launched. When checked, the List's layout isn't generated until the List is on screen. For example, if the List is contained in a panel that is not currently displayed, the app will not render the List if Delay render till visible is enabled until the user navigates to the panel containing the List .