百度地图系列05——显示屏幕范围内的marker
百度地图系列05——显示屏幕范围内的marker
原理：根据屏幕中心点坐标和屏幕的长宽计算出屏幕左上角和右下角坐标，然后判断所显示的marker是否在这个范围内。
中心点坐标：
LatLng mCenterLatLng = status.target;
double lat = mCenterLatLng.latitude;
double lng = mCenterLatLng.longitude;屏幕的宽度和高度：
WindowManager wm = this.getWindowManager();
//这种方法已被淘汰
// int width = wm.getDefaultDisplay().getWidth();
// int height = wm.getDefaultDisplay().getHeight();
DisplayMetrics outMetrics = new DisplayMetrics();
wm.getDefaultDisplay().getMetrics(outMetrics);
int width = outMetrics.widthPixels;
int height = outMetrics.heightPixels;左上角经纬度：
Point pt = new Point();
pt.x = 0;
pt.y = 0;
LatLng ll = mBaiduMap.getProjection().fromScreenLocation(pt);右下角经纬度：
Point ptr = new Point();
ptr.x = width;
ptr.y = height;
LatLng llr = mBaiduMap.getProjection().fromScreenLocation(ptr);判断是否在屏幕范围内并添加marker:
if(ll_right.latitude<lat&&lat<ll_left.latitude&&ll_left.longitude<lng&&lng<ll_right.longitude){
LatLng ll_pt = new LatLng(lat, lng);
Log.i("this is", lat+","+lng);
BitmapDescriptor bitmap = BitmapDescriptorFactory.fromResource(R.drawable.icon_gcoding);
// MarkerOptions markerOption = new MarkerOptions().icon(bitmap).position(ll_pt);
OverlayOptions options = new MarkerOptions()
.position(ll_pt)
.icon(bitmap)
.zIndex(12)
.draggable(true);
marker = (Marker) mBaiduMap.addOverlay(options);
} 用的baiduapi如下图所示：
完整代码，里面还包括定位代码：
package com.yds.newpowerbike.activity;
import java.util.ArrayList;
import com.baidu.location.BDLocation;
import com.baidu.location.BDLocationListener;
import com.baidu.location.LocationClient;
import com.baidu.location.LocationClientOption;
import com.baidu.mapapi.SDKInitializer;
import com.baidu.mapapi.map.BaiduMap;
import com.baidu.mapapi.map.BaiduMap.OnMapStatusChangeListener;
import com.baidu.mapapi.map.BitmapDescriptor;
import com.baidu.mapapi.map.BitmapDescriptorFactory;
import com.baidu.mapapi.map.MapStatus;
import com.baidu.mapapi.map.MapStatusUpdate;
import com.baidu.mapapi.map.MapStatusUpdateFactory;
import com.baidu.mapapi.map.MapView;
import com.baidu.mapapi.map.Marker;
import com.baidu.mapapi.map.MarkerOptions;
import com.baidu.mapapi.map.MyLocationData;
import com.baidu.mapapi.map.OverlayOptions;
import com.baidu.mapapi.model.LatLng;
import com.yds.newpowerbike.R;
import com.yds.newpowerbike.bean.PolePoint;
import com.yds.newpowerbike.net.ConnectServerIml;
import com.yds.newpowerbike.net.ShareData;
import com.yds.newpowerbike.util.JsonParse;
import android.app.Activity;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.graphics.Point;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.WindowManager;
public class ConcernAct extends Activity{
private MapView mMapView;
private LocationClient mLocClient;
public MyLocationListener1 myListener1 = new MyLocationListener1();;
BaiduMap mBaiduMap;
boolean isLocationClientStop = false;
boolean isFirstLoc = true;
ArrayList<String>PoleName,PoleAddress,PoleFix;
ConnectServerIml iml;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
SDKInitializer.initialize(getApplicationContext());
setContentView(R.layout.activity_concern);
mMapView = (MapView) findViewById(R.id.concern_map);
mBaiduMap = mMapView.getMap();
mBaiduMap.setMyLocationEnabled(true);
mLocClient = new LocationClient(this);
mLocClient.registerLocationListener(myListener1);
LocationClientOption option = new LocationClientOption();
option.setIsNeedAddress(true);
option.setOpenGps(true);
option.setCoorType("bd09ll");
option.setScanSpan(1000);
mLocClient.setLocOption(option);
mLocClient.start();
mBaiduMap.setOnMapStatusChangeListener(new OnMapStatusChangeListener() {
@Override
public void onMapStatusChangeStart(MapStatus arg0) {
// TODO Auto-generated method stub
}
@Override
public void onMapStatusChangeFinish(MapStatus status) {
// TODO Auto-generated method stub
updateMapState(status);
}
@Override
public void onMapStatusChange(MapStatus arg0) {
// TODO Auto-generated method stub
}
});
}
private void updateMapState(MapStatus status){
LatLng mCenterLatLng = status.target;
double lat = mCenterLatLng.latitude;
double lng = mCenterLatLng.longitude;
Log.i("中心点坐标", lat+","+lng);
WindowManager wm = this.getWindowManager();
// int width = wm.getDefaultDisplay().getWidth();
// int height = wm.getDefaultDisplay().getHeight();
DisplayMetrics outMetrics = new DisplayMetrics();
wm.getDefaultDisplay().getMetrics(outMetrics);
int width = outMetrics.widthPixels;
int height = outMetrics.heightPixels;
Log.i("屏幕宽度和高度", width+","+height);
Point pt = new Point();
pt.x = 0;
pt.y = 0;
LatLng ll = mBaiduMap.getProjection().fromScreenLocation(pt);
Log.i("左上角经纬度", ll.latitude+","+ll.longitude);
Point ptr = new Point();
ptr.x = width;
ptr.y = height;
LatLng llr = mBaiduMap.getProjection().fromScreenLocation(ptr);
Log.i("右下角经纬度", llr.latitude+","+llr.longitude);
SharedPreferences shared = getSharedPreferences("point", 0);
Editor editor = shared.edit();
editor.putString("leftPointx", String.valueOf(ll.latitude));
editor.putString("leftPointy", String.valueOf(ll.longitude));
editor.putString("rightPointx", String.valueOf(llr.latitude));
editor.putString("rightPointy", String.valueOf(llr.longitude));
editor.commit();
// if (!shared.getString("cityName", "null").equals("")) {
// Log.i("cityName", shared.getString("cityName", "null"));
// }
//这里是从服务器端获取坐标点，这里你们可以自定义坐标点
new Thread(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
String url = ShareData.CHARGE_SEARCH;
iml = new ConnectServerIml();
String result = iml.ConcernByClientGet(url);
ArrayList<PolePoint>list = JsonParse.search(result);
PolePoint pp;
PoleName = new ArrayList<String>();
PoleAddress = new ArrayList<String>();
PoleFix = new ArrayList<String>();
for (int i = 0; i < list.size(); i++) {
pp = list.get(i);
PoleName.add(pp.getPoleName());
PoleAddress.add(pp.getPoleAdress());
PoleFix.add(pp.getPoleFix());
}
Bundle bundle = new Bundle();
Message msg = new Message();
msg.what = 0x01;
bundle.putStringArrayList("PoleName", PoleName);
bundle.putStringArrayList("PoleAddress", PoleAddress);
bundle.putStringArrayList("PoleFix", PoleFix);
msg.setData(bundle);
handler.sendMessage(msg);
}
}).start();
}
Handler handler = new Handler(){
public void handleMessage(Message msg) {
super.handleMessage(msg);
if(msg.what==0x01){
SharedPreferences shared = getSharedPreferences("point", 0);
LatLng ll_left = new LatLng(Double.valueOf(shared.getString("leftPointx", "")),
Double.valueOf(shared.getString("leftPointy", "")));
LatLng ll_right = new LatLng(Double.valueOf(shared.getString("rightPointx", "")),
Double.valueOf(shared.getString("rightPointy", "")));
Marker marker;
for(int i = 0;i<msg.getData().getStringArrayList("PoleFix").size();i++){
iml = new ConnectServerIml();
String pt = msg.getData().getStringArrayList("PoleFix").get(i);
double lat = iml.getLat(pt);
double lng = iml.getLng(pt);
// Log.i("Tag", lat+","+lng);
Log.i("this is", ll_right.latitude+","+ll_left.latitude);
if(ll_right.latitude<lat&&lat<ll_left.latitude&&ll_left.longitude<lng&&lng<ll_right.longitude){
LatLng ll_pt = new LatLng(lat, lng);
Log.i("this is", lat+","+lng);
BitmapDescriptor bitmap = BitmapDescriptorFactory.fromResource(R.drawable.icon_gcoding);
// MarkerOptions markerOption = new MarkerOptions().icon(bitmap).position(ll_pt);
OverlayOptions options = new MarkerOptions()
.position(ll_pt)
.icon(bitmap)
.zIndex(12)
.draggable(true);
marker = (Marker) mBaiduMap.addOverlay(options);
}
}
}
};
};
public class MyLocationListener1 implements BDLocationListener{
@Override
public void onReceiveLocation(BDLocation location) {
// TODO Auto-generated method stub
if(location == null||isLocationClientStop)
return;
MyLocationData locData = new MyLocationData.Builder()
.accuracy(location.getRadius())
.direction(100)
.latitude(location.getLatitude())
.longitude(location.getLongitude())
.build();
mBaiduMap.setMyLocationData(locData);
if(isFirstLoc){
isFirstLoc = false;
LatLng ll = new LatLng(location.getLatitude(),
location.getLongitude());
MapStatusUpdate u = MapStatusUpdateFactory.newLatLng(ll);
mBaiduMap.animateMapStatus(u);
}
SharedPreferences shared = getSharedPreferences("city", 0);
Editor editor = shared.edit();
String city = location.getCity()+"this";
if(!city.equals("this")){
editor.putString("cityName", location.getCity());
editor.commit();
}
}
}
@Override
public void onDestroy() {
// TODO Auto-generated method stub
// mLocClient.stop();
// mBaiduMap.setMyLocationEnabled(false);
// mMapView = null;
mMapView.onDestroy();
super.onDestroy();
}
@Override
public void onPause() {
// TODO Auto-generated method stub
super.onPause();
mMapView.onPause();
}
@Override
public void onResume() {
// TODO Auto-generated method stub
super.onResume();
mMapView.onResume();
}
}
运行截图：
因为涉及项目原因，而且重新写一个比较烦，所以这里就不给源码下载了，以后或许会补上。