本实例主要是针对四川地理信息中心的切片,如果利用ArcGIS for Android API进行解析,并读入作用底图。
1)基础准备:下载Java版的Json解析库(
http://code.google.com/p/json-simple/)、熟悉四川地理信息中心切片规则
2)关于四川地理信息中心的切片规则这就不做介绍了,在以前专题已介绍过,详见:
http://www.scgis.net/
3)代码说明
AgsLOD.java:切片等级信息定义文件,在这定义了比例尽、等级、分辨率
[java] view plaincopy
- package com.esri.arcgis.android.samples;
-
- import com.esri.core.internal.d.c;
-
- public class AgsLOD extends c {
- private static final long serialVersionUID = 4341699179151728883L;
-
- private int level;
- private double resolution;
- private double scale;
-
- public AgsLOD(int level, double scale, double resolution) {
- super();
-
- this.level = level;
- this.scale = scale;
- this.resolution = resolution;
- }
-
- public int a() {
- return this.level;
- }
-
- public double b() {
- return this.resolution;
- }
-
- public double c() {
- return this.scale;
- }
- }
GetToken.java:通过Web请求提交用户名跟密码,获取Token字符口串,并对字符串进行解析,用于获取地图切片。
[java] view plaincopy
- package com.esri.arcgis.android.samples;
-
- import java.io.BufferedReader;
- import java.io.InputStreamReader;
- import java.net.HttpURLConnection;
- import java.net.URL;
-
- public class GetToken {
- //get token
- public String sendPost(String url) {
- StringBuilder result = new StringBuilder();
- try {
- URL httpurl = new URL(url);
- HttpURLConnection httpConn = (HttpURLConnection) httpurl
- .openConnection();
- httpConn.setDoInput(true);
- BufferedReader in = new BufferedReader(new InputStreamReader(
- httpConn.getInputStream(),"UTF-8"));
- String line;
- while ((line = in.readLine()) != null) {
- result .append(line);
- }
- //System.out.println(result);
- in.close();
- //get token
- return result.toString().split("\"")[15];
- } catch (Exception e) {
- e.printStackTrace();
- }
- return null;
- }}
SCGISModel.java:切片参数定义文件,包括切片的空间参考等基础信息
[java] view plaincopy
- package com.esri.arcgis.android.samples;
-
- import java.io.BufferedInputStream;
- import java.io.ByteArrayOutputStream;
- import java.io.File;
- import java.net.HttpURLConnection;
- import java.net.URL;
- import com.esri.core.geometry.Envelope;
- import com.esri.core.geometry.SpatialReference;
- import com.esri.core.internal.d.k;
-
- import com.esri.core.map.TiledLayerModel;
-
- public class SCGISModel extends TiledLayerModel {
- private static final long serialVersionUID = 7726567118839553087L;
-
- private String location;
- private String token;
- public SCGISModel(String location, SpatialReference sr, Envelope full,
- k tileInfo) {
- super(sr, full, tileInfo);
- this.location = location;
- this.token=new GetToken().sendPost("http://www.scgis.net.cn/imap/iMapServer/Token/getToken?username=test20110703&password=test20110703&IpAddress=&TimeSpan=100M&st=1302073818076");
- }
-
- @Override
- public byte[] getTile(int level, int row, int col) throws Exception {
- byte[] result = null;
- try {
- int levelCustom = level + 1;
- String bundlesDir = location
- + levelCustom
- + File.separator
- + row
- + File.separator
- + col
- + "?token="+this.token;
- ;
-
- ByteArrayOutputStream bos = new ByteArrayOutputStream();
-
- URL sjwurl = new URL(bundlesDir);
- HttpURLConnection httpUrl = null;
- BufferedInputStream bis = null;
- byte[] buf = new byte[1024];
-
- httpUrl = (HttpURLConnection) sjwurl.openConnection();
- httpUrl.connect();
- bis = new BufferedInputStream(httpUrl.getInputStream());
-
- while (true) {
- int bytes_read = bis.read(buf);
- if (bytes_read > 0) {
- bos.write(buf, 0, bytes_read);
- } else {
- break;
- }
- }
- ;
- bis.close();
- httpUrl.disconnect();
-
- result = bos.toByteArray();
-
- } catch (Exception ex) {
- ex.printStackTrace();
- }
-
- return result;
- }
-
- }
SCGISMapServices.java:继承tiledLayer,自定义切片类。
[java] view plaincopy
- package com.esri.arcgis.android.samples;
- import java.util.ArrayList;
- import android.content.Context;
- import android.util.AttributeSet;
-
- import com.esri.android.map.TiledLayer;
- import com.esri.core.geometry.Envelope;
- import com.esri.core.geometry.Point;
- import com.esri.core.geometry.SpatialReference;
- import com.esri.core.internal.d.c;
- import com.esri.core.internal.d.k;
- import com.esri.core.map.TiledLayerModel;
-
- public class SCGISMapServices extends TiledLayer {
- private String location = "http://www.scgis.net.cn/iMap/iMapServer/NewRest/services/SCTileMap/tile/";
-
- private SpatialReference spatialReference = SpatialReference.create(4326);
- private Envelope fullExtent = new Envelope(95.918, 24.898, 110.14, 35.209);
- private k tileInfo;
-
- public SCGISMapServices(Context context, AttributeSet attrs) {
- super(context, attrs);
- try {
- init();
- } catch (Exception ex) {
- ex.printStackTrace();
- }
- }
-
- @Override
- protected TiledLayerModel initModel() throws Exception {
- return new SCGISModel(location, spatialReference, fullExtent, tileInfo);
- }
-
- private void init() {
- try {
- tileInfo = new k();
- tileInfo.f = new Point(-180, 90);
-
-
- tileInfo.a = 256;
- tileInfo.b = 256;
- tileInfo.h = new ArrayList<c>();
-
- double resolution = 0.010998662747496;
- double scale=4622333.68;
- for (int j = 0, jcount = 11; j < jcount; j++) {
- int level = j;
- tileInfo.h.add(new AgsLOD(level, scale, resolution));
- resolution/=2;
- scale/=2;
- }
- } catch (Exception e) {
- e.printStackTrace();
- }
- }
-
- }
4)效果图如下:
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http://blog.csdn.net/esrichinacd/article/details/7782424