cityguidemidlet.java

手机地图软件,还未完全做出来,是用NETBEAN和做的

            } catch (LocationException e) {
                e.printStackTrace();
                destroyApp(false);
                notifyDestroyed();

                return;
            }
        } else {
            cityMap.setCategories(selectedCategories);
        }

        if (mapCanvas == null) {
            mapCanvas = new MapCanvas(cityMap);
            mapCanvas.addCommand(exitCommand);
            mapCanvas.addCommand(detailsCommand);
            mapCanvas.addCommand(settingsCommand);
            mapCanvas.setCommandListener(this);
        }

        display.setCurrent(mapCanvas);
    }

    /**
     * Initializes map display and sets listener for location updates
     * use LocationProvider defaults
     */
    public void showMapCanvas(boolean updateLandmarks) {
        if (updateLandmarks || (mapCanvas == null)) {
            Form progressForm = new Form(null);
            progressForm.append(new StringItem("Generating map...", null));
            display.setCurrent(progressForm);

            Thread mapGeneratorThread =
                new Thread() {
                    public void run() {
                        generateAndDisplayMap();
                    }
                };

            mapGeneratorThread.start();
        } else {
            display.setCurrent(mapCanvas);
        }
    }

    /**
     * Show error screen with last error
     */
    public void showErrorForm(String message) {
        if (errorAlert == null) {
            errorAlert = new Alert("Error", message, null, AlertType.ERROR);
            errorAlert.addCommand(closeCommand);
            errorAlert.setCommandListener(this);
        }

        errorAlert.setString(message);
        display.setCurrent(errorAlert);
    }

    /**
     * Progress screen while loading landmarks
     * Especially while creating new landmark store from
     * text resource file
     */
    public void showProgressScreen(String title, int size) {
        if (progressGauge == null) {
            progressGauge = new Gauge(title, false, size, 0);
            progressGauge.setLayout(Item.LAYOUT_CENTER | Item.LAYOUT_EXPAND | Item.LAYOUT_VCENTER);
        }

        progressGauge.setValue(0);

        if (progressScreen == null) {
            progressScreen = new Form(null);
            progressScreen.append(progressGauge);
            progressScreen.addCommand(exitCommand);
            ProgressScreen_nextCommand = new Command("Next", Command.SCREEN, 1);
            progressScreen.setCommandListener(this);
        }

        display.setCurrent(progressScreen);
    }

    /**
     * Settings screen let user select categories
     * of points of interest he/she is interested in.
     * Only those will be displayed on the map.
     * Contains choice group of categories
     */
    public void showSettingsScreen(boolean show) {
        if (settingsScreen == null) {
            String[] categories = Util.asArray(landmarkStore.getCategories());
            Image[] images = new Image[categories.length];

            for (int i = 0; i < categories.length; i++)
                images[i] = imageManager.getImage(categories[i]);

            Item[] items =
                new Item[] {
                    new StringItem(null, SETTINGS_TEXT),
                    new ChoiceGroup(CHOICEGRP_TEXT, ChoiceGroup.MULTIPLE, categories, images)
                };
            settingsScreen = new Form("Settings", items);

            boolean[] flags = new boolean[categories.length];

            for (int i = 0; i < flags.length; i++) {
                flags[i] = true;
            }

            ((ChoiceGroup)settingsScreen.get(1)).setSelectedFlags(flags);
            SettingsScreen_backCommand = new Command("Back", Command.SCREEN, 1);
            settingsScreen.addCommand(SettingsScreen_backCommand);
            settingsScreen.setCommandListener(this);
        }

        if (show) {
            display.setCurrent(settingsScreen);
        }
    }

    /**
     * Details screen contains detailed info about
     * landmarks. It's used for landmarks which
     * appear in proximity radius.
     */
    public void showDetailsScreen() {
        MapLandmark[] mapLandmarks = cityMap.getMapLandmarks();
        int numActive = 0;

        for (int i = 0; i < mapLandmarks.length; ++i) {
            if (mapLandmarks[i].isActive()) {
                ++numActive;
            }
        }

        Item[] items = null;

        if (numActive == 0) {
            items = new Item[] { new StringItem(null, NOLANDMARK_TEXT) };
        } else {
            int NUMBER_OF_ITEMS = 7;
            items = new Item[numActive * NUMBER_OF_ITEMS];

            Landmark l = null;
            AddressInfo address = null;
            int i = 0;

            for (int j = 0; j < mapLandmarks.length; ++j) {
                if (mapLandmarks[j].isActive()) {
                    l = (Landmark)mapLandmarks[j].getLandmark();
                    address = l.getAddressInfo();
                    items[i] = new StringItem("Name:", l.getName());
                    items[i + 1] = new StringItem("Description:", l.getDescription());
                    items[i + 2] = new StringItem("Street:", address.getField(AddressInfo.STREET));
                    items[i + 3] = new StringItem("Postal Code:",
                            address.getField(AddressInfo.POSTAL_CODE));
                    items[i + 4] = new StringItem("City:", address.getField(AddressInfo.CITY));
                    items[i + 5] = new StringItem("Phone No:",
                            address.getField(AddressInfo.PHONE_NUMBER));
                    items[i + 6] = new StringItem(" ", " ");
                    i += NUMBER_OF_ITEMS;
                }
            }
        }

        detailsScreen = new Form("Details", items);
        DetailsScreen_backCommand = new Command("Back", Command.SCREEN, 1);
        detailsScreen.addCommand(DetailsScreen_backCommand);
        detailsScreen.setCommandListener(this);
        display.setCurrent(detailsScreen);
    }

    /**
     * Simple welcome screen
     */
    public void showWelcomeScreen() {
        if (welcomeScreen == null) {
            Item[] items =
                new Item[] {
                    new StringItem(null, WELCOME_TEXT),
                    new ImageItem(null, imageManager.getImage("logo"), Item.LAYOUT_CENTER, "logo"),
                };
            welcomeScreen = new Form("City Guide", items);
            WelcomeScreen_nextCommand = new Command("Next", Command.SCREEN, 2);
            welcomeScreen.addCommand(exitCommand);
            welcomeScreen.addCommand(WelcomeScreen_nextCommand);
            welcomeScreen.setCommandListener(this);
        }

        display.setCurrent(welcomeScreen);
    }

    /** is map display on */
    public boolean isMapDisplayed() {
        return (display.getCurrent() == mapCanvas);
    }

    /** which categories are selected */
    public Vector getSelectedCategories() {
        return selectedCategories;
    }

    /**
     * Update map display - categories have changed
     */
    public void selectedCategoriesChanged() {
        selectedCategories = new Vector();

        ChoiceGroup cg = (ChoiceGroup)settingsScreen.get(1);

        for (int i = 0; i < cg.size(); i++) {
            if (cg.isSelected(i)) {
                selectedCategories.addElement(cg.getString(i));
            }
        }
    }

    /**
     * Get landmarks of the categories in given extent
     */
    public Vector getLandmarks(String[] categories, double minLat, double minLon, double maxLat,
        double maxLon) {
        Vector landmarks = new Vector();

        for (int i = 0; i < categories.length; i++) {
            Enumeration l = null;

            try {
                l = landmarkStore.getLandmarks(categories[i], minLat, minLon, maxLat, maxLon);
            } catch (IOException ioe) {
                ioe.printStackTrace();
            }

            for (; l.hasMoreElements();) {
                landmarks.addElement(l.nextElement());
            }
        }

        return landmarks;
    }

    /**
     * Load all images
     */
    private void loadImages() {
        try {
            String name = null;

            while (!landmarksLoaded) {
                synchronized (this) {
                    wait();
                }
            }

            imageManager.loadImagesCache(landmarkStore.getCategories());
            imageManager.loadImagesCache(PRELOAD_IMAGES);
            commandAction(ProgressScreen_nextCommand, null);
        } catch (Exception ioe) {
            ioe.printStackTrace();
        }
    }

    /**
     * Load landmarks from text resources
     */
    private void loadLandmarks() {
        final InputStream is = getClass().getResourceAsStream("/waypoints.txt");

        try {
            landmarkStore = LandmarkStore.getInstance(LANDMARKSTORE_NAME);

            if (null == landmarkStore) {
                LandmarkStore.createLandmarkStore(LANDMARKSTORE_NAME);
                landmarkStore = LandmarkStore.getInstance(LANDMARKSTORE_NAME);
                Util.readLandmarksFromStream(landmarkStore, is, progressGauge);
            }

            landmarksLoaded = true;

            synchronized (this) {
                notify();
            }
        } catch (Exception ioe) {
            ioe.printStackTrace();
            lastError = "Cannot read landmarks.\n Landmark store wasn't created." +
                ioe.getMessage();

            try {
                LandmarkStore.deleteLandmarkStore(LANDMARKSTORE_NAME);
                commandAction(showErrorCommand, null);
            } catch (Exception e) {
                //do nothing
            }
        }
    }
}