Regarding to the low level and high level UI of MIDP1.0/2.0, i come up with the following question when working on the case study of the HYP .
I have a simple Calculator application, and its UI is developed using high-level user interface components such as Form, StringItem,Item,TextField. In this case supposedly high-level GUI components are rendered by mobile devices, hence it allows devices to present the components in an appropriate manner. However, when my application was tested on Nokia emulator (all emulator of Series 40), it turned out that the UI only covers part of the screen, and the string item is not presented appropriately.
I looked at Nokia UI API, and found that the package com.nokia.mid.ui contains some graphic extensions only for low level UI API, such as Graphic and Canvas.
My question is what is the reason behind the the above wierd behaviour. Is it because of the implementation or is it because of the specific Virtual Machine implementation of the phone manufacturer?