Starting MicroUI

  1. To get started, first we need to add MicroUI, a Foundation Library that provides an abstraction layer to access the low-level UI inputs and outputs.

  2. Look for module.ivy, and replace dependencies with the following:

    <dependencies>
       <dependency org="ej.api" name="microui" rev="3.0.3"/>
    </dependencies>
    

    Note

    There’s no need to add EDC as a dependency. It will be automatically resolved with the correct version (as a dependency of the MicroUI library).

  3. This call initializes the MicroUI framework and starts the UI Thread, which manages the user input and display events.

    public static void main(String[] args) {
       MicroUI.start();
    }
    

    Note

    MicroUI has to be started before any UI operations.

  4. To run your code on the Simulator, left click on the Project Go To Run > Run As > MicroEJ Application.

    Note

    If you have several platforms you will be asked which to use.

    ../../_images/simulator.png

Widgets

  1. The widget library provides a collection of common widgets and containers. It is based on MWT, a base library that defines core type graphical elements for designing rich graphical user interface embedded applications.

  2. Look for module.ivy, and replace dependencies with the following:

    <dependencies>
       <dependency org="ej.library.ui" name="widget" rev="4.0.0" />
    </dependencies>
    

    Note

    There’s no need to add MWT or MicroUI, as both are dependencies of the Widget library. They will be automatically resolved with the correct version.

Desktop Usage

  1. A desktop is the top-level object that can be displayed on a Display. It may contain a widget, and at most one desktop is shown on a Display at any given time.

  2. Desktop automatically triggers the layout and rendering phases for itself and its children.

    public static void main(String[] args) {
       MicroUI.start();
    
       Desktop desktop = new Desktop();
       desktop.requestShow();
    }
    

Displaying a Label

  1. To add a label, just instantiate a Label object and add it to the desktop as the root widget.

    public static void main(String[] args) {
       MicroUI.start();
       Desktop desktop = new Desktop();
    
       Label label = new Label("Hello World");
       desktop.setWidget(label);
    
       desktop.requestShow();
    }
    
  2. To run the code go to the Main.java file and right click it, hover over Run As and select MicroEJ Application.

    ../../_images/runapplication.png ../../_images/hello.png