android - 单击 map 上的图标位置时的事件

Question

我使用类 Overlay 来标记 map 上的位置。我想在单击 map 上的图标时显示位置信息(显示 atm_name 和 atm_address)。我尝试了 onTap 方法，但当我单击时它会显示所有图标的所有信息。我应该使用哪种方法来解决我的问题..帮助我。抱歉我英文不好

我的代码:

public class atm_markerATM extends Overlay{

    Double lat;
    Double lng;
    Context ct;
    String atm_name;
    String atm_address;

    @Override
    public void draw(Canvas canvas, MapView mapView, boolean shadow) {
        Projection projection = mapView.getProjection();
        if (shadow == false) {
            Double latitude = lat*1E6;
            Double longitude = lng*1E6;
            GeoPoint geoPoint;
            geoPoint = new GeoPoint(latitude.intValue(),longitude.intValue());

            // Convert the location to screen pixelats
            Point point = new Point();
            projection.toPixels(geoPoint, point);

            // Setup the paint
            Paint paint = new Paint();

            Bitmap mBitmap = BitmapFactory.decodeResource(ct.getResources(), R.drawable.hoe);
            canvas.drawBitmap(mBitmap, point.x-8, point.y-38, paint);
        }
        super.draw(canvas, mapView, shadow);
    }

    @Override
    public boolean onTap(GeoPoint point, MapView mapView) {
        return false;
    }

    public void setLocation(Double lat, Double lng, Context ct, String name, String address) {
        this.lat = lat;
        this.lng = lng;
        this.ct = ct;
        this.atm_name = name;
        this.atm_address = address;
    }
}

Answer 1

我在 Overlay 中使用了 OnTap，效果很好。

在我的 Draw 方法中，我填充了一个 ArrayList 对象，这些对象代表显示的实体(在您的例子中是 ATM)。这些对象中的每一个都有一个纬度和经度值。

在 onTap 中，我将点击的点与 ArrayList 中每个对象的纬度/经度(在绘制期间填充)进行比较。如果水龙头击中的点非常接近某个对象，那么我可以显示它的详细信息。

我有一些源代码，如果这听起来像您想要的方式，我可以在某个时候发布。

[编辑] 这是源代码，我已经破解了您需要的部分。请注意，有一些您不需要的对 bubbleLayouts 等的引用，但将它们留在其中更容易。

请注意，做任何事情总是有不止一种方法 - 这可能不是最好的方法，但它对我有用 ;-)

import java.util.ArrayList;
import java.util.Iterator;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Point;
import android.graphics.RectF;
import android.view.View;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapView;
import com.google.android.maps.Projection;
import com.google.android.maps.MapView.LayoutParams;
import com.google.android.maps.Overlay;

public class EnhancedStationOverlay extends Overlay {

private MapView _mapView;
private Context _context;
private LinearLayout _bubbleLayout;
private int _defaultMarker;
private ArrayList<station> _stationLocations;
private ArrayList<station> _displayedStations;

// private RectF debugHitRect = new RectF();

public EnhancedStationOverlay(int defaultMarker, MapView mapView, LinearLayout bubbleLayout, ArrayList<station> stationList) {
    _stationLocations = stationList;
    _mapView = mapView;
    _context = mapView.getContext();
    _bubbleLayout = bubbleLayout;
    _defaultMarker = defaultMarker;
}

public boolean onTap(GeoPoint p, MapView mapView) {

    station tappedStation = FetchTappedStation(mapView, p);

    if (tappedStation != null) {

        // Display Bubble containing Location Details
    }

    return true;
}

@Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {

    Projection projection = mapView.getProjection();
    super.draw(canvas, mapView, shadow);

    // Need to resolve top, bottom, left and right coordinates in relation to the map

    // Height & Width
    int latSpan = mapView.getLatitudeSpan();
    int lngSpan = mapView.getLongitudeSpan();

    // Centre Point
    GeoPoint mapCenter = mapView.getMapCenter();

    // Left and Right
    int mapLeftGeo = mapCenter.getLongitudeE6() - (lngSpan / 2);
    int mapRightGeo = mapCenter.getLongitudeE6() + (lngSpan / 2);

    // Top and Bottom
    int mapTopGeo = mapCenter.getLatitudeE6() - (latSpan / 2);
    int mapBottomGeo = mapCenter.getLatitudeE6() + (latSpan / 2);

    if (shadow != false) {
        // Create an empty ArrayList
        _displayedStations = new ArrayList<station>();

        // Loop through stations
        for (station currentStation : _stationLocations) {

            // Resolve current station location to a GeoPoint
            GeoPoint point = new GeoPoint((int) currentStation.getLatitude(), (int) currentStation.getLongitude());

            // Determine whether it falls within the screens view of the map
            if ((point.getLatitudeE6() > mapTopGeo && point.getLatitudeE6() < mapBottomGeo)
                    && (point.getLongitudeE6() > mapLeftGeo && point.getLongitudeE6() < mapRightGeo)) {

                // Yes it does - configure and place marker (pushpin)
                Point myPoint = new Point();
                projection.toPixels(point, myPoint);

                Bitmap stationMarker = BitmapFactory.decodeResource(_context.getResources(), _defaultMarker);
                canvas.drawBitmap(stationMarker, myPoint.x - 15, myPoint.y - 30, null);

                // Add this location to the collection of displayed locations
                _displayedStations.add(currentStation);
            }
        }
    }
}

private station FetchTappedStation(MapView mapView, GeoPoint geo) {

    // As in Draw() - Need to resolve top, bottom, left and right coordinates in relation to the map (could refactor this)
    int latSpan = mapView.getLatitudeSpan();
    int lngSpan = mapView.getLongitudeSpan();
    GeoPoint mapCenter = mapView.getMapCenter();
    int mapLeftGeo = mapCenter.getLongitudeE6() - (lngSpan / 2);
    int mapRightGeo = mapCenter.getLongitudeE6() + (lngSpan / 2);
    int mapTopGeo = mapCenter.getLatitudeE6() - (latSpan / 2);
    int mapBottomGeo = mapCenter.getLatitudeE6() + (latSpan / 2);

    // Track which MapLocation was hit…if any
    station hitMapLocation = null;

    RectF hitTestRecr = new RectF();
    Point screenCoords = new Point();
    Point tappedCoords = new Point();

    Iterator<station> iterator = _displayedStations.iterator();

    // Iterate over displayed stations...
    while (iterator.hasNext()) {
        station testLocation = iterator.next();

        // Translate MapLocation lat/long to screen coordinates
        GeoPoint test = new GeoPoint((int) testLocation.getLatitude(), (int) testLocation.getLongitude());

        Projection projection = mapView.getProjection();
        projection.toPixels(test, screenCoords);

        if (screenCoords.x != 0 && screenCoords.y != 0) {
            // Create a 'hit testing' rectangle
            hitTestRecr.set(-20, -50, 20, 15);

            // Next, offset the Rectangle 'surround' current location’s
            // icon on the screen.
            hitTestRecr.offset(screenCoords.x, screenCoords.y);

            // Finally test for match between ‘hit’ Rectangle and
            // location clicked by the user.
            // If a hit occurred, then we stop processing and return the
            // result;
            projection.toPixels(geo, tappedCoords);
            if (hitTestRecr.contains(tappedCoords.x, tappedCoords.y)) {
                hitMapLocation = testLocation;
                break;
            }
        }

    }

    return hitMapLocation;
}