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Using Line User Interface with Oracle Java ME Embedded 8.1 on STMicroelectronics Evaluation board

Oracle Java
ME Embedded 8.1 Developers Preview
for ST Micro Evaluation board has been
recently released. 

I mentioned in my previous post, one of the release additions is
a Line User Interface (LUI) API hardware implementation. LUI is an optional API
of MEEP (JSR 361), which enables rendering text information on a
display. In Java ME Embedded 8.0 this functionality was supported only by Java ME SDK Emulator and now it is possible to use a hardware
display to implement a simple user interaction in Java ME Embedded

ME SDK 8.1 update includes a very good LUI sample. The sample is an
on-screen text menu navigated by a built-in joystick. The menu has 12 items,
several nested items, and a status line reflecting a current user choice.  Code of the sample is accompanied very detailed comments, which can definitely helps start developing interactive
applications very fast.

is a basic example that demonstrates the use of the built-in screen on STM32429I-EVAL board with Java ME Embedded and LUI API.

 Happy Java coding for embedded.

import java.util.Iterator;
import javax.microedition.lui.Display;
import javax.microedition.lui.DisplayColor;
import javax.microedition.lui.DisplayListener;
import javax.microedition.midlet.MIDlet;
public class LUIDemo extends MIDlet implements DisplayListener {@Overridepublic void startApp() {// Get Display instance and configure it
        Iterator<Display> displays = Display.getDisplays(false);
        Display myDisplay = displays.next();// Assign a state change listner to Display instance
        myDisplay.addDisplayListener((DisplayListener) this);//as soon as the hardware display will be assigned to myDisplay instance//hardwareStateChanged method will be invoked with newState = true synchronized (myDisplay) {try {// Assign hadware display to myDisplay 
                myDisplay.setHardwareAssigned(true);// Assigning display may take some time,// so that we need to wait the operation acomplishement 
                myDisplay.wait();// Now myDisplay has HW display assigned and we can use it} catch (InterruptedException ex) {
                ex.printStackTrace();}}//Display.setText is overloaded method. //In the example below the text "Hello world" is blinking.
        myDisplay.setText(0, "Hello world", true, false);
        myDisplay.setText(1, "I love programming Java ME Embedded on STM32429EVAL");}@Overridepublic void destroyApp(boolean unconditional) {}@Override// hardwareStateChanged method is invoked as the hardware display is assigned or unassignedpublic void hardwareStateChanged(Display d, boolean newState) {//Setting up assigned hardware display
        d.setLightingColor(new DisplayColor(0xFF, 0, 0));
        d.setCurrentTextColor(new DisplayColor(0, 0, 0xFF));
        d.setBackgroundColor(new DisplayColor(0, 0, 0));// notify all threads are waiting for Display Objectsynchronized (d) {
            d.notifyAll();}}@Overridepublic void displayAdded(Display d) {}@Overridepublic void displayRemoved(Display d) {}

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