I am currently developing a complex (multiple pages of nested navs/tabs) web application using R's Shiny package.
I am currently experiencing an issue where sometimes accessing the values of these sliders from R via input$ returns NULL for no apparent reason. When this happens, the various outputs dependent on these sliders cannot be produced due to errors.
This problem goes away if the user forces the application to recalculate by changing an input.
The error occurs primarily at startup, though on occasion it will occur in the middle of a session as the user plays with the inputs.
I am currently working on a clean example to reproduce this, but if anyone has experienced this before or has any ideas I would certainly appreciate the help.