Unfortunately it's not possible. What you can do is update application icon.
Also there are alternative ways of notification:
Notification Service for Blackberry OS 4.5 application
Update Application Icon
Background running application:
public class NotifIconSrvc extends Application {
private int mCount = 0;
private int mSize = 0;
public NotifIconSrvc() {
Timer timer = new Timer();
timer.schedule(sendEventTask, 1000, 3000);
}
TimerTask sendEventTask = new TimerTask() {
public void run() {
// Post the GlobalEvent.
// Long = ci.samples.45.notificon
ApplicationManager.getApplicationManager().postGlobalEvent(
0x5a9f7caa171ab7b8L, mCount++, mSize++);
}
};
public static void main(String[] args) {
NotifIconSrvc app = new NotifIconSrvc();
app.enterEventDispatcher();
}
}
Main application:
public class NotifIconApp extends UiApplication
implements GlobalEventListener {
private Bitmap mIcon = Bitmap.getBitmapResource("icon.png");
private Bitmap mIconActive =
Bitmap.getBitmapResource("icon_active.png");
private Scr mScreen = new Scr();
public NotifIconApp() {
addGlobalEventListener(this);
pushScreen(mScreen);
}
public static void main(String[] args) {
NotifIconApp app = new NotifIconApp();
app.enterEventDispatcher();
}
public void eventOccurred(long guid, int count, int size,
Object object0, Object object1) {
if (0x5a9f7caa171ab7b8L == guid) {
Bitmap icon = getUpdateIconBitmap(mIcon, count, size);
HomeScreen.updateIcon(icon);
Bitmap rolloverIcon =
getUpdateIconBitmap(mIconActive, count, size);
HomeScreen.setRolloverIcon(rolloverIcon);
mScreen.updateScreen(count, size);
}
}
private Bitmap getUpdateIconBitmap(Bitmap bmp, int count, int size) {
int width = bmp.getWidth();
int height = bmp.getHeight();
Bitmap iconBmp = new Bitmap(width, height);
Graphics g = new Graphics(iconBmp);
XYRect rect = new XYRect(0, 0, width, height);
g.drawBitmap(rect, bmp, 0, 0);
g.setFont(g.getFont().derive(Font.BOLD, 20, Ui.UNITS_px,
Font.ANTIALIAS_STANDARD, Font.COLORED_OUTLINE_EFFECT));
String text = Integer.toString(count);
g.setColor(Color.BLACK);
g.drawText(text, 0, 2);
text = Integer.toString(size) + " Kb";
g.setColor(Color.GREEN);
g.drawText(text, 0, height - 22);
return iconBmp;
}
}
class Scr extends MainScreen {
LabelField mMessages;
String mLabelText = "message count: ";
String mTitleText = "message counter";
public Scr() {
add(mMessages = new LabelField(mLabelText));
setTitle(mTitleText);
}
void updateScreen(int count, int size) {
StringBuffer sb = new StringBuffer(Integer.toString(count));
sb.append("/");
sb.append(Integer.toString(size));
sb.append("Kb");
String text = sb.toString();
setTitle(mTitleText + "(" + text + ")");
mMessages.setText(mLabelText + text);
}
protected void makeMenu(Menu menu, int instance) {
super.makeMenu(menu, instance);
menu.add(mMenuGoBG);
}
MenuItem mMenuGoBG = new MenuItem("go background", 0, 0) {
public void run() {
UiApplication.getUiApplication().requestBackground();
}
};
}