android中有点聚类的代码吗？我怎样才能在没有性能问题的情况下加载千针？
【问题讨论】：
标签： android maps android-mapview markerclusterer
昨晚我在 Android MapView 上使用了 PointClustering。看到社区没有任何东西，所以我想分享。
如果它们在 mapView 中的投影太近，则对地理点进行分组。也只渲染可见点。
更新
代码从头开始重写。
现在可以在GitHub
【讨论】：
public void draw(Canvas canvas, MapView mapView, boolean shadow) 应该去哪里？
我对上面的代码进行了修改，并控制了地图视图中覆盖图标的数量，并将组和单点分开。
我的代码：
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);
}
}
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);
}
}
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。
我希望这会对某人有所帮助。
【讨论】：
Google 的 Android Map Utils 对此有解决方案：Google Maps Android Marker Clustering Utility。
添加依赖
implementation 'com.google.maps.android:android-maps-utils:0.5'
制作你自己的 ClusterItem
class MyItem(
private val position: LatLng,
val title: String,
private val snippet: String
) : ClusterItem {
override fun getPosition() = position
override fun getTitle() = title
override fun getSnippet() = snippet
}
设置集群管理器并添加项目
override fun onMapReady(googleMap: GoogleMap) {
val clusterManager = ClusterManager<MyItem>(this, googleMap)
googleMap.setOnCameraIdleListener(clusterManager)
clusterManager.addItem(MyItem(LatLng(51.51, -0.12), "title", "snippet"))
}
就是这样！项目现在显示如下：
自定义图标
为了自定义图标，将val icon: BitmapDescriptor添加到您的ClusterItem并更改集群管理器的渲染器：
clusterManager.renderer = object : DefaultClusterRenderer<MyItem>(this, googleMap, clusterManager) {
override fun onBeforeClusterItemRendered(item: MyItem, markerOptions: MarkerOptions) {
markerOptions.icon(item.icon)
}
}
使项目可点击
根据经验，与标记的任何交互都应通过集群管理器进行。这同样适用于使项目可点击。
googleMap.setOnMarkerClickListener(clusterManager)
clusterManager.setOnClusterItemClickListener {
Toast.makeText(this, "Clicked on item ${it.title}", Toast.LENGTH_SHORT).show()
true
}
同样，您可以调用googleMap.setOnInfoWindowClickListener(clusterManager) 和clusterManager.setOnClusterItemInfoWindowClickListener 来处理信息窗口上的点击。
【讨论】：
在 github 上有一个关于 Polaris 库 (https://github.com/cyrilmottier/Polaris) 的拉取请求，它添加了集群：
【讨论】：
还有this answer，它只需要你覆盖你的 Overlay 的 draw 方法。它将您的 mapView 分成多个部分，因此它不那么复杂。但至少它奏效了。
【讨论】：
对于 ANDROID V2，这里是集群代码
大家好
我查看了各种库，发现它们非常复杂，一个词都听不懂，所以我决定制作自己的聚类算法 这是我在java中的代码
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;
}
只需在此处传入包含纬度和经度的数组列表 然后显示集群 函数来了
@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)));
}
}
任何问题或疑虑请询问将清除它们......谢谢
【讨论】：