Use of variable changes expected behaviour of LVGL function

[rghince]

I am trying to do as much UI work as I can in flow to avoid implementation of multiple interface management functions in my code (and also development should be faster when I am more capable of using it). Currently, I am obtaining the index of a drop down to set the text of a label elsewhere using a variable 'spdunits_index'; the variable is analysed using a series of compare actions and the label is set accordingly (see screenshot below). This works well - previously I was using native code to achieve this. However this does not manage the initialisation of the selected index of the drop down before its host screen is called, so I am trying to achieve this.

My ESP32 code obtains saved widget state settings from flash and initialises widgets using the following code:

  // Check if key exists, create and initialise if not
  if (prefs.isKey("spdunits")) {
    spdunits = prefs.getChar("spdunits"); // 0 = kph, 1 = mph, 2 = m/s
  } else prefs.putChar("spdunits",0);
  lv_dropdown_set_selected(objects.dd_speed_units, (uint32_t)spdunits);

Before I created the flow to set the label, the above initialisation worked as expected. However it no longer does so. I am trying to understand why this no longer works... and this is my question. Why not?

Thanks,

Richard

(screenshots follow)

This is the setup of the drop down index variable (it is not native).