Low Level API

Principle

The MicroUI implementation for MicroEJ requires a Low Level implementation. This Low Level implementation finalizes the MicroUI implementation started with the static initialization step (see Static Initialization) for a given MicroEJ Platform.

The Low Level implementation consists of a set of headers files to implement in C to target the hardware drivers. Some functions are mandatory, others are not. Some other headers files are also available to call UI engines internal functions.

For the simulator, some Front Panel interfaces and classes allow to specify the simulated platform characteristics.

Embedded Platform

MicroUI Low Level

MicroUI Embedded Low Level API

The specification of header files names is:

  • Name starts with LLUI_.
  • Second part name refers the UI engine: DISPLAY, INPUT, LED.
  • Files whose name ends with _impl list functions to implement over hardware.
  • Files whose name has no suffix list internal UI engines functions.

There are some exceptions :

  • LLUI_PAINTER_impl.h and LLDW_PAINTER_impl.h list a subpart of UI Graphics Engine functions to implement (all MicroUI native drawing methods).
  • ui_drawing.h and dw_drawing.h list all drawing methods the platform can implement.
  • ui_drawing_soft.h and dw_drawing_soft.h list all drawing methods implemented by the Graphics Engine.
  • microui_constants.h is the file generated by the MicroUI Static Initializer (see Static Initialization).

All header files and their aims are described in next UI engines chapters: LED, Input and Display.

Simulator

MicroUI Low Level

MicroUI Simulator Low Level API

In the simulator the three UI engines are grouped in a mock called Front Panel. The Front Panel comes with a set of classes and interfaces which are the equivalent of headers file (*.h) of Embedded Platform.

The specification of class names is:

  • Package are the same than the MicroUI library (ej.microui.display, ej.microui.event, ej.microui.led).
  • Name start with LLUI.
  • Second part name refers the UI engine: Display, Input, Led.
  • Files whose name ends with Impl list methods to implement like embedded platform.
  • Files whose name has no suffix list internal UI engines functions.

There are some exceptions :

  • LLUIPainter.java and LLDWPainter.java list a subpart of UI Graphics Engine functions (all MicroUI native drawing methods).
  • UIDrawing.java and DWDrawing.java list all drawing methods the platform can implement (and already implemented by the Graphics Engine).
  • EventXXX list methods to create input events compatible with MicroUI implementation.

All files and their aims are described in Simulation.