Android地图点集群
在android中有点集群的代码吗？ 如何在不出现性能问题的情况下加载千点精确度？
昨晚我在Android MapView上进入了PointClustering。 看到社区没有什么东西，所以我想分享。
如果它们在mapView中的投影太靠近，则对这些地点进行分组。 也渲染只有可见的地方。
UPDATE
代码从scrach返回。
现在在GitHub上
- 代码从头开始重新编写
- 使用GVM聚类algorithm（相当快，但没有像我的聚簇点那么好）
- 很快也join了以前的聚类algorithm
我已经在上面的代码中进行了修改，并在地图视图中控制了叠加图标的号码，并将组和单点分开。
我的代码：
MMapView.java
import java.util.ArrayList; import java.util.List; import android.content.Context; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.drawable.BitmapDrawable; import android.graphics.drawable.Drawable; import android.util.AttributeSet; import com.google.android.maps.GeoPoint; import com.google.android.maps.MapView; import com.google.android.maps.Overlay; import com.impiger.maphighlight.R; //Reference - http://stackoverflow.com/questions/7447350/android-maps-point-clustering public class MMapView extends MapView { private static final String TAG = MMapView.class.getSimpleName(); private static final int MAX_VISIBLE_POINTS = 1; private PMapViewOverlay itemizedOverlay; private List<Overlay> mapOverlays; private List<GeoPoint> geoPoints = new ArrayList<GeoPoint>(); private BitmapDrawable drawable; private Context context; private Drawable emptyDrawable; private int count; private int oldZoomLevel = -1; ArrayList<OverlayItemExtended> mOverlays; public MMapView(Context context, AttributeSet attrs) { super(context, attrs); this.context = context; mapOverlays = getOverlays(); drawable = new BitmapDrawable( BitmapFactory.decodeResource(getResources(), R.drawable.blue_65)); itemizedOverlay = new PMapViewOverlay(drawable, context); emptyDrawable = context.getResources().getDrawable( R.drawable.marker); mOverlays = new ArrayList<OverlayItemExtended>(); init(); } private GeoPoint getPoint(double lat, double lon) { return (new GeoPoint((int) (lat * 1000000.0), (int) (lon * 1000000.0))); } private void init(){ putPoint(11, 77, true); putPoint(11.5, 76.6, false); putPoint(10.98383, 77.32112, false); putPoint(10, 77, false); putPoint(11, 78, false); putPoint(11, 77.5, false); putPoint(10.5, 77, false); putPoint(12, 77, false); putPoint(11.77, 77.11, false); putPoint(12.1, 78.33, false); putPoint(11.83, 77.293, false); putPoint(11.12, 77, false); putPoint(11.13, 77, false); putPoint(11.14, 77, false); putPoint(11.15, 77, false); putPoint(11.12, 77.2, false); putPoint(11.13, 77.34, false); putPoint(11.14, 77.4, false); putPoint(11.15, 77.1977, false); putPoint(11.347373, 77.5627783, true); putPoint(11.53454, 76.696645, false); putPoint(10.19282, 77.847373, false); putPoint(10.4728, 76.39388, false); putPoint(11.4563, 78, false); putPoint(11.73663, 77.5927, false); putPoint(10.5674, 77.6762, false); putPoint(12.02882, 77.672782, false); putPoint(11.7767876, 77.1123423, false); putPoint(12.18332, 78.33, false); putPoint(11.8393883, 77.293938783, false); putPoint(11.388323, 77.9478723, false); putPoint(11.1345645, 77.97723, false); putPoint(11.1423423, 77.73774, false); putPoint(11.1552, 77.793783, false); putPoint(11.127895434, 77.2944554, false); putPoint(11.13232345, 77.342234, false); putPoint(11.14456573, 77.4, false); putPoint(11.159765, 77.1977, false); } public void putPoint(double lat, double lon, boolean isMyPosition) { int latitude = (int) (lat * 1E6); int longitude = (int) (lon * 1E6); GeoPoint geo = new GeoPoint(latitude, longitude); geo = getPoint(lat, lon); /* * Remove doubles */ Boolean alreadyExists = false; for (GeoPoint item : geoPoints) { if (item.getLatitudeE6() == geo.getLatitudeE6() && item.getLongitudeE6() == geo.getLongitudeE6()) { alreadyExists = true; } } if (!alreadyExists) { geoPoints.add(geo); } } /* * Place the overlays */ public void placeOverlays() { itemizedOverlay.removeAllOverlays(); getOverlays().clear(); mapOverlays.clear(); mOverlays.clear(); int i = 1; for (GeoPoint item : geoPoints) { OverlayItemExtended overlayitem = new OverlayItemExtended(item, "title "+i, "snippet"); // Here is where the magic happens addOverlayItemClustered(overlayitem, this, geoPoints.size()); i++; } for(int j=0;j<mOverlays.size();j++){ OverlayItemExtended overlayItem = mOverlays.get(j); if(overlayItem.isMaster){ if(overlayItem.slaves.size() > 0){ itemizedOverlay = new PMapViewOverlay(drawable, context); itemizedOverlay.addOverlayItem(overlayItem); }else{ itemizedOverlay = new PMapViewOverlay(emptyDrawable, context); itemizedOverlay.addOverlayItem(overlayItem); } mapOverlays.add(itemizedOverlay); } } } /* * Update the points at panned / zoom etc */ public void dispatchDraw(Canvas canvas) { super.dispatchDraw(canvas); if (getZoomLevel() != oldZoomLevel) { placeOverlays(); } oldZoomLevel = getZoomLevel(); } public void addOverlayItemClustered(OverlayItemExtended thisOverlay, MapView mapView, int totalPoints) { for (OverlayItemExtended otherOverlay : mOverlays) { /* * Thresshold for the clustering */ /* * Zoom level >15 don't cluster If less than Max_Visible_points * don't cluster */ if (mapView.getZoomLevel() >= 14 || (MAX_VISIBLE_POINTS > totalPoints) && PointCluster.getOverLayItemDistance(thisOverlay, otherOverlay, mapView) > 60) { mOverlays.add(thisOverlay); return; } if (PointCluster.getOverLayItemDistance(thisOverlay, otherOverlay, mapView) < 90 && !thisOverlay.isClustered) { // Here is where the clustering actually happens if (otherOverlay.isMaster) { thisOverlay.isMaster = false; // otherOverlay.isMaster = false; thisOverlay.isClustered = true; otherOverlay.isClustered = true; otherOverlay.slaves.push(thisOverlay); thisOverlay.parent = otherOverlay; } else if (PointCluster.getOverLayItemDistance(thisOverlay, otherOverlay.parent, mapView) < 90 && otherOverlay.isClustered) { thisOverlay.isMaster = false; thisOverlay.isClustered = true; thisOverlay.parent = otherOverlay.parent; otherOverlay.parent.slaves.push(thisOverlay); } } } mOverlays.add(thisOverlay); } }
OverlayItemExtended.java
import java.util.Stack; import com.google.android.maps.GeoPoint; import com.google.android.maps.OverlayItem; public class OverlayItemExtended extends OverlayItem { public boolean isClustered = false; public boolean isMaster = true; public boolean isMe = false; public OverlayItemExtended parent; public Stack<OverlayItemExtended> slaves = new Stack<OverlayItemExtended>(); public OverlayItemExtended(GeoPoint point, String title, String snippet) { super(point, title, snippet); } }
PMapViewOverlay.java
import java.util.ArrayList; import android.content.Context; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Point; import android.graphics.drawable.Drawable; import android.widget.Toast; import com.google.android.maps.GeoPoint; import com.google.android.maps.ItemizedOverlay; import com.google.android.maps.MapView; @SuppressWarnings("rawtypes") public class PMapViewOverlay extends ItemizedOverlay { private static final String TAG = PMapViewOverlay.class.getSimpleName(); private Context context; private ArrayList<OverlayItemExtended> mOverlays; public PMapViewOverlay(Drawable defaultMarker, Context context) { super(boundCenterBottom(defaultMarker)); this.context = context; mOverlays = new ArrayList<OverlayItemExtended>(); paint.setTextAlign(Paint.Align.CENTER); paint.setTextSize(25); paint.setAntiAlias(true); paint.setStrokeWidth(5); paint.setColor(Color.WHITE); } @Override protected OverlayItemExtended createItem(int i) { return mOverlays.get(i); } @Override public int size() { return mOverlays.size(); } public void addOverlayItem(OverlayItemExtended overlay) { mOverlays.add(overlay); populate(); } public void removeAllOverlays() { mOverlays.clear(); populate(); } public void removePointsButMe() { for (int i = 0; i < mOverlays.size(); i++) { OverlayItemExtended overlay = mOverlays.get(i); if (overlay.isMe) { mOverlays.clear(); addOverlayItem(overlay); break; } } populate(); } Paint paint = new Paint(); @Override public void draw(Canvas canvas, MapView mapView, boolean shadow) { super.draw(canvas, mapView, shadow); // cycle through all overlays for (int index = 0; index < mOverlays.size(); index++) { OverlayItemExtended item = mOverlays.get(index); // Converts lat/lng-Point to coordinates on the screen GeoPoint point = item.getPoint(); Point ptScreenCoord = new Point(); mapView.getProjection().toPixels(point, ptScreenCoord); if (item.isMaster) { if (item.slaves.size() > 0) { canvas.drawText(item.slaves.size() + 1 + "", ptScreenCoord.x, ptScreenCoord.y - 13, paint); } } } } @Override protected boolean onTap(int index) { OverlayItemExtended item = mOverlays.get(index); if (item.isMaster) { if (item.slaves.size() == 0) { Toast.makeText(context, "You tapped item " + item.getTitle(), Toast.LENGTH_LONG).show(); } } return super.onTap(index); } }
我没有更改PointCluster.java中的任何代码。
我希望这会帮助别人。 
有一个很好的例子。 请在此处查看： http : //code.google.com/p/android-playground-erdao/source/browse/trunk/SampleClusterMap/?r=226
github上有一个针对Polaris库（https://github.com/cyrilmottier/Polaris）的pull请求，它增加了集群：;
也有这个答案只需要你重写你的覆盖的绘制方法。 它将你的mapView分成几部分，所以它不太复杂。 但至less它工作。
这里的ANDROID V2这里是集群代码
大家好
我看了各种图书馆，发现他们如此complexx不能理解一个字，所以我决定让我自己的cluteringalgorithm这里去我的代码在Java
static int OFFSET = 268435456; static double RADIUS = 85445659.4471; static double pi = 3.1444; public static double lonToX(double lon) { return Math.round(OFFSET + RADIUS * lon * pi / 180); } public static double latToY(double lat) { return Math.round(OFFSET - RADIUS * Math.log((1 + Math.sin(lat * pi / 180)) / (1 - Math.sin(lat * pi / 180))) / 2); } public static int pixelDistance(double lat1, double lon1, double lat2, double lon2, int zoom) { double x1 = lonToX(lon1); double y1 = latToY(lat1); double x2 = lonToX(lon2); double y2 = latToY(lat2); return (int) (Math .sqrt(Math.pow((x1 - x2), 2) + Math.pow((y1 - y2), 2))) >> (21 - zoom); } static ArrayList<Cluster> cluster(ArrayList<Marker> markers, int zoom) { ArrayList<Cluster> clusterList = new ArrayList<Cluster>(); ArrayList<Marker> originalListCopy = new ArrayList<Marker>(); for (Marker marker : markers) { originalListCopy.add(marker); } /* Loop until all markers have been compared. */ for (int i = 0; i < originalListCopy.size();) { /* Compare against all markers which are left. */ ArrayList<Marker> markerList = new ArrayList<Marker>(); for (int j = i + 1; j < markers.size();) { int pixelDistance = pixelDistance(markers.get(i).getLatitude(), markers.get(i).getLongitude(), markers.get(j) .getLatitude(), markers.get(j).getLongitude(), zoom); if (pixelDistance < 40) { markerList.add(markers.get(i)); markerList.add(markers.get(j)); markers.remove(j); originalListCopy.remove(j); j = i + 1; } else { j++; } } if (markerList.size() > 0) { Cluster cluster = new Cluster(clusterList.size(), markerList, markerList.size() + 1, originalListCopy.get(i) .getLatitude(), originalListCopy.get(i) .getLongitude()); clusterList.add(cluster); originalListCopy.remove(i); markers.remove(i); i = 0; } else { i++; } /* If a marker has been added to cluster, add also the one */ /* we were comparing to and remove the original from array. */ } return clusterList; }
只要在你的数组列表中传入包含经度和纬度的数组，然后在这里显示出簇就是函数
@Override public void onTaskCompleted(ArrayList<FlatDetails> flatDetailsList) { LatLngBounds.Builder builder = new LatLngBounds.Builder(); originalListCopy = new ArrayList<FlatDetails>(); ArrayList<Marker> markersList = new ArrayList<Marker>(); for (FlatDetails detailList : flatDetailsList) { markersList.add(new Marker(detailList.getLatitude(), detailList .getLongitude(), detailList.getApartmentTypeString())); originalListCopy.add(detailList); builder.include(new LatLng(detailList.getLatitude(), detailList .getLongitude())); } LatLngBounds bounds = builder.build(); int padding = 0; // offset from edges of the map in pixels CameraUpdate cu = CameraUpdateFactory.newLatLngBounds(bounds, padding); googleMap.moveCamera(cu); ArrayList<Cluster> clusterList = Utils.cluster(markersList, (int) googleMap.getCameraPosition().zoom); // Removes all markers, overlays, and polylines from the map. googleMap.clear(); // Zoom in, animating the camera. googleMap.animateCamera(CameraUpdateFactory.zoomTo(previousZoomLevel), 2000, null); CircleOptions circleOptions = new CircleOptions().center(point) // // setcenter .radius(3000) // set radius in meters .fillColor(Color.TRANSPARENT) // default .strokeColor(Color.BLUE).strokeWidth(5); googleMap.addCircle(circleOptions); for (Marker detail : markersList) { if (detail.getBhkTypeString().equalsIgnoreCase("1 BHK")) { googleMap.addMarker(new MarkerOptions() .position( new LatLng(detail.getLatitude(), detail .getLongitude())) .snippet(String.valueOf("")) .title("Flat" + flatDetailsList.indexOf(detail)) .icon(BitmapDescriptorFactory .fromResource(R.drawable.bhk1))); } else if (detail.getBhkTypeString().equalsIgnoreCase("2 BHK")) { googleMap.addMarker(new MarkerOptions() .position( new LatLng(detail.getLatitude(), detail .getLongitude())) .snippet(String.valueOf("")) .title("Flat" + flatDetailsList.indexOf(detail)) .icon(BitmapDescriptorFactory .fromResource(R.drawable.bhk_2))); } else if (detail.getBhkTypeString().equalsIgnoreCase("3 BHK")) { googleMap.addMarker(new MarkerOptions() .position( new LatLng(detail.getLatitude(), detail .getLongitude())) .snippet(String.valueOf("")) .title("Flat" + flatDetailsList.indexOf(detail)) .icon(BitmapDescriptorFactory .fromResource(R.drawable.bhk_3))); } else if (detail.getBhkTypeString().equalsIgnoreCase("2.5 BHK")) { googleMap.addMarker(new MarkerOptions() .position( new LatLng(detail.getLatitude(), detail .getLongitude())) .snippet(String.valueOf("")) .title("Flat" + flatDetailsList.indexOf(detail)) .icon(BitmapDescriptorFactory .fromResource(R.drawable.bhk2))); } else if (detail.getBhkTypeString().equalsIgnoreCase("4 BHK")) { googleMap.addMarker(new MarkerOptions() .position( new LatLng(detail.getLatitude(), detail .getLongitude())) .snippet(String.valueOf("")) .title("Flat" + flatDetailsList.indexOf(detail)) .icon(BitmapDescriptorFactory .fromResource(R.drawable.bhk_4))); } else if (detail.getBhkTypeString().equalsIgnoreCase("5 BHK")) { googleMap.addMarker(new MarkerOptions() .position( new LatLng(detail.getLatitude(), detail .getLongitude())) .snippet(String.valueOf("")) .title("Flat" + flatDetailsList.indexOf(detail)) .icon(BitmapDescriptorFactory .fromResource(R.drawable.bhk5))); } else if (detail.getBhkTypeString().equalsIgnoreCase("5+ BHK")) { googleMap.addMarker(new MarkerOptions() .position( new LatLng(detail.getLatitude(), detail .getLongitude())) .snippet(String.valueOf("")) .title("Flat" + flatDetailsList.indexOf(detail)) .icon(BitmapDescriptorFactory .fromResource(R.drawable.bhk_5))); } else if (detail.getBhkTypeString().equalsIgnoreCase("2 BHK")) { googleMap.addMarker(new MarkerOptions() .position( new LatLng(detail.getLatitude(), detail .getLongitude())) .snippet(String.valueOf("")) .title("Flat" + flatDetailsList.indexOf(detail)) .icon(BitmapDescriptorFactory .fromResource(R.drawable.bhk_2))); } } for (Cluster cluster : clusterList) { BitmapFactory.Options options = new BitmapFactory.Options(); options.inMutable = true; options.inPurgeable = true; Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.cluster_marker, options); Canvas canvas = new Canvas(bitmap); Paint paint = new Paint(); paint.setColor(getResources().getColor(R.color.white)); paint.setTextSize(30); canvas.drawText(String.valueOf(cluster.getMarkerList().size()), 10, 40, paint); googleMap.addMarker(new MarkerOptions() .position( new LatLng(cluster.getClusterLatitude(), cluster .getClusterLongitude())) .snippet(String.valueOf(cluster.getMarkerList().size())) .title("Cluster") .icon(BitmapDescriptorFactory.fromBitmap(bitmap))); } }
任何问题或疑问请询问将清除所有………..谢谢
