欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页  >  移动技术

Android实现在map上画出路线的方法

程序员文章站 2024-01-04 10:53:40
本文实例讲述了android实现在map上画出路线的方法。分享给大家供大家参考。具体如下: 最近在搞在地图上画出路线图,经过一段时间的摸索,终于搞明白了,其实也挺简单的,...

本文实例讲述了android实现在map上画出路线的方法。分享给大家供大家参考。具体如下:

最近在搞在地图上画出路线图,经过一段时间的摸索,终于搞明白了,其实也挺简单的,写个类继承overlay,并重写draw方法,在draw方法中画出 path即可。对于overaly,在地图上标记某个点或者画线之类的就要使用overlay,overlay相当于一个覆盖物,覆盖在地图上,这个覆盖物要自己实现所以要继承overlay。

mapactivity.java如下:

package net.blogjava.mobile.map; 
import java.util.list; 
import android.app.alertdialog; 
import android.graphics.bitmap; 
import android.graphics.bitmapfactory; 
import android.graphics.canvas; 
import android.graphics.color; 
import android.graphics.paint; 
import android.graphics.path; 
import android.graphics.point; 
import android.location.address; 
import android.location.geocoder; 
import android.os.bundle; 
import android.view.menu; 
import com.google.android.maps.geopoint; 
import com.google.android.maps.mapactivity; 
import com.google.android.maps.mapcontroller; 
import com.google.android.maps.mapview; 
import com.google.android.maps.overlay; 
import com.google.android.maps.projection; 
public class main extends mapactivity { 
private geopoint gpoint1, gpoint2, gpoint3;// 连线的点 
@override 
public void oncreate(bundle savedinstancestate) { 
 super.oncreate(savedinstancestate); 
 setcontentview(r.layout.main); 
 mapview mapview = (mapview) findviewbyid(r.id.mapview); 
 mapview.setclickable(true); 
 mapview.setbuiltinzoomcontrols(true); 
 mapcontroller mapcontroller = mapview.getcontroller(); 
 mapview.settraffic(true);// 交通图 
 // mapview.setsatellite(true);//卫星图 
 // mapview.setstreetview(true);//街景 
 myoverlay myoverlay = new myoverlay(); 
 mapview.getoverlays().add(myoverlay); 
 mapcontroller.setzoom(15);// 初始放大倍数 
 gpoint1 = new geopoint((int) (24.477384 * 1000000), 
 (int) (118.158216 * 1000000)); 
 gpoint2 = new geopoint((int) (24.488967 * 1000000), 
 (int) (118.144277 * 1000000)); 
 gpoint3 = new geopoint((int) (24.491091 * 1000000), 
 (int) (118.136781 * 1000000)); 
 mapcontroller.animateto(gpoint1); 
} 
@override 
protected boolean isroutedisplayed() { 
 // todo auto-generated method stub 
 return false; 
} 
class myoverlay extends overlay { 
 @override 
 public void draw(canvas canvas, mapview mapview, boolean shadow) { 
 // todo auto-generated method stub 
 super.draw(canvas, mapview, shadow); 
 // 画笔 
 paint paint = new paint(); 
 paint.setcolor(color.red); 
 paint.setdither(true); 
 paint.setstyle(paint.style.stroke); 
 paint.setstrokejoin(paint.join.round); 
 paint.setstrokecap(paint.cap.round); 
 paint.setstrokewidth(2); 
 projection projection = mapview.getprojection(); 
 point p1 = new point(); 
 point p2 = new point(); 
 point p3 = new point(); 
 projection.topixels(gpoint1, p1); 
 projection.topixels(gpoint2, p2); 
 projection.topixels(gpoint3, p3); 
 path path = new path(); 
 path.moveto(p1.x, p1.y); 
 path.lineto(p2.x, p2.y); 
 path.lineto(p3.x, p3.y); 
 canvas.drawpath(path, paint);// 画出路径 
 } 
} 
}

main.xml如下:

<?xml version="1.0" encoding="utf-8"?> 
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android" 
 android:orientation="vertical" android:layout_width="fill_parent" 
 android:layout_height="fill_parent"> 
 <com.google.android.maps.mapview 
 android:id="@+id/mapview" android:layout_width="fill_parent" 
 android:layout_height="fill_parent" 
 android:apikey="0ib7kn70qp1lt216hhb-jmhj8gltie4p63o77kq" /> 
</linearlayout>

最后别忘了加权限 :
 
<uses-permission android:name="android.permission.internet"/>
 
在<applacation></applacation>之间加<uses-library android:name="com.google.android.maps" />

绘制路线图:

/** 
* 通过解析google map返回的xml,在map中画路线图
*/ 
public void drawroute(){
 string url = "http://maps.google.com/maps/api/directions/xml?origin=23.055291,113.391802" + "&destination=23.046604,113.397510&sensor=false&mode=walking"; 
 httpget get = new httpget(url); 
 string strresult = ""; 
 try { 
  httpparams httpparameters = new basichttpparams(); 
  httpconnectionparams.setconnectiontimeout(httpparameters, 3000); 
  httpclient httpclient = new defaulthttpclient(httpparameters); 
  httpresponse httpresponse = null; 
  httpresponse = httpclient.execute(get); 
  if (httpresponse.getstatusline().getstatuscode() == 200){ 
  strresult = entityutils.tostring(httpresponse.getentity()); 
  } 
 } catch (exception e) { 
  return; 
 } 
 if (-1 == strresult.indexof("<status>ok</status>")){ 
  toast.maketext(this, "获取导航路线失败!", toast.length_short).show(); 
  this.finish(); 
  return; 
 } 
 int pos = strresult.indexof("<overview_polyline>"); 
 pos = strresult.indexof("<points>", pos + 1); 
 int pos2 = strresult.indexof("</points>", pos); 
 strresult = strresult.substring(pos + 8, pos2); 
 list<geopoint> points = decodepoly(strresult); 
 myoverlay moverlay = new myoverlay(points); 
 list<overlay> overlays = mmapview.getoverlays(); 
 overlays.add(moverlay); 
 if (points.size() >= 2){ 
  mmapcontroller.animateto(points.get(0)); 
 } 
 mmapview.invalidate(); 
 } 
/** 
* 解析返回xml中overview_polyline的路线编码 
* 
* @param encoded 
* @return 
*/ 
private list<geopoint> decodepoly(string encoded) { 
 list<geopoint> poly = new arraylist<geopoint>(); 
 int index = 0, len = encoded.length(); 
 int lat = 0, lng = 0; 
 while (index < len) { 
  int b, shift = 0, result = 0; 
  do { 
  b = encoded.charat(index++) - 63; 
  result |= (b & 0x1f) << shift; 
  shift += 5; 
  } while (b >= 0x20); 
  int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1)); 
  lat += dlat; 
  shift = 0; 
  result = 0; 
  do { 
  b = encoded.charat(index++) - 63; 
  result |= (b & 0x1f) << shift; 
  shift += 5; 
  } while (b >= 0x20); 
  int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1)); 
  lng += dlng; 
  geopoint p = new geopoint((int) (((double) lat / 1e5) * 1e6),(int) (((double) lng / 1e5) * 1e6)); 
  poly.add(p); 
 } 
 return poly; 
}

希望本文所述对大家的android程序设计有所帮助。

上一篇:

下一篇: