Step 2: LocationMidlet.java

Begin with the class LocationMidlet and the method startApp. These construct the UI and add it to a form. The UI displays the current location and zoom level.

1. Add the following function to LocationMidlet.java:

   public void startApp() { form = new Form("LocationMIDlet"); testCommand = new Command("Test", Command.OK, 1); gmCommand = new Command("Google Maps", Command.OK, 3); exitCommand = new Command("Exit", Command.EXIT, 1); form.addCommand(testCommand); form.addCommand(gmCommand); form.addCommand(exitCommand); form.setCommandListener(this); latitudeString = new StringItem("Latitude:", "0"); form.append(latitudeString); longitudeString = new StringItem("Longitude:", "0"); form.append(longitudeString); zoomGauge = new Gauge("Zoom level", true, 17, 12); form.append(zoomGauge); Display.getDisplay(this).setCurrent(form); }

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2. Add the ability to get the current location. These values are saved to the attributes latitude and longitude and are displayed on the screen.

   Add the following functions to LocationMidlet.java:

   public void run() { askLocation(); } private void askLocation() { form.append("\nWait, getting location..."); try { // Create a Criteria object for defining desired selection // criteria Criteria cr = new Criteria(); // Specify horizontal accuracy of 500 meters, leave other // parameters at default values. cr.setHorizontalAccuracy(500); LocationProvider lp = LocationProvider.getInstance(cr); // get the location, five minutes timeout Location l = lp.getLocation(300); Coordinates c = l.getQualifiedCoordinates(); if (c != null) { latitude = c.getLatitude(); longitude = c.getLongitude(); latitudeString.setText("" + latitude); longitudeString.setText("" + longitude); System.out.println("latitude: " + latitude); System.out.println("longitude: " + longitude); } } catch (LocationException le) { // not able to retrive location information form.delete(form.size() - 1); form.append("\nLocationException: " + le.getMessage()); } catch (InterruptedException ie) { form.delete(form.size() - 1); form.append("\nInterruptedException: " + ie.getMessage()); } form.delete(form.size() - 1); }

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3. Add the implementation to handle actions of commands. TestCommand starts a new thread and returns the new locations. gmCommand displays a map at the current location if the location is known.

   Add the following function to LocationMidlet.java:.

   public void commandAction(Command c, Displayable d) { if (c == testCommand) { thread = new Thread(this); thread.start(); } if (c == gmCommand) { while (form.size() > 3) { form.delete(form.size() - 1); } GoogleMaps gm = new GoogleMaps(); if (latitude != 0 && longitude != 0) { Image map = null; try { int zoom_int = zoomGauge.getValue(); map = gm.retrieveStaticImage(240, 320, latitude, longitude, zoom_int, "png32"); } catch (Exception ex) { ex.printStackTrace(); } if (map != null) { form.append(map); } } } if (c == exitCommand) { thread = null; notifyDestroyed(); } }

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Note that no implementation is needed for the methods pauseApp and destroyApp.