The Map Tile API serves map tiles obtained by mapping points on the surface of a sphere (the globe) to points on a plane, using the normalized Mercator projection.
It's a example of using HERE Map Tile REST API on Android (not Native SDK).
MainActivity.java
package com.example.androidhererestmapimage;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import android.support.v7.app.ActionBarActivity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.os.Bundle;
import android.widget.ImageView;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.TextView;
public class MainActivity extends ActionBarActivity {
public class LoadHereMapTask extends AsyncTask<URL, Void, Bitmap> {
ImageView imageView;
LoadHereMapTask(ImageView v){
imageView = v;
}
@Override
protected Bitmap doInBackground(URL... params) {
Bitmap bm = null;
URL urlMapImage = params[0];
try {
bm = BitmapFactory.decodeStream(urlMapImage.openConnection().getInputStream());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return bm;
}
@Override
protected void onPostExecute(Bitmap result) {
imageView.setImageBitmap(result);
}
}
SeekBar sbZoom;
TextView textviewMapRqs512, textviewMapRqs256;
ImageView mapImage1, mapImage2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
textviewMapRqs512 = (TextView)findViewById(R.id.maprqs512);
textviewMapRqs256 = (TextView)findViewById(R.id.maprqs256);
mapImage1 = (ImageView)findViewById(R.id.mapimage1);
mapImage2 = (ImageView)findViewById(R.id.mapimage2);
sbZoom = (SeekBar)findViewById(R.id.sbzoom);
sbZoom.setOnSeekBarChangeListener(new OnSeekBarChangeListener(){
@Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// TODO Auto-generated method stub
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
updateHereMap();
}});
updateHereMap();
}
private void updateHereMap(){
URL urlTarget;
try {
String strTarget512 = genHereMapTileRequest("/512");
textviewMapRqs512.setText(strTarget512);
urlTarget = new URL(strTarget512);
new LoadHereMapTask(mapImage1).execute(urlTarget);
String strTarget256 = genHereMapTileRequest("/256");
textviewMapRqs256.setText(strTarget256);
urlTarget = new URL(strTarget256);
new LoadHereMapTask(mapImage2).execute(urlTarget);
} catch (MalformedURLException e) {
e.printStackTrace();
}
}
private String getMercatorProjection(double lat, double lon, int z){
/*
* reference:
* http://developer.here.com/rest-apis/documentation/enterprise-map-tile/topics/key-concepts.html
*/
double latRad = lat * Math.PI/180;
double n = Math.pow(2, z);
double xTile = n * ((lon + 180)/360);
double yTile = n * (1-(Math.log(Math.tan(latRad) + 1/Math.cos(latRad))/Math.PI))/2;
String strProjection = "/"+ String.valueOf(z)
+ "/" + String.valueOf((int)xTile)
+ "/" + String.valueOf((int)yTile);
return strProjection;
}
private String genHereMapTileRequest(String pixelCnt){
String BaseURL = "http://1.base.maps.cit.api.here.com";
String Path = "/maptile/2.1/";
String Resource = "maptile";
String Version = "/newest";
String NormalDay = "/normal.day";
String ApplicationId = "DemoAppId01082013GAL"; //for demo
String ApplicationCode = "AJKnXv84fjrb0KIHawS0Tg"; //for demo
String png8 = "/png8";
int zoom = sbZoom.getProgress();
//Berlin
String strZoomColumnRow = getMercatorProjection(52.525439, 13.38727, zoom);
String rqs = BaseURL + Path + Resource + Version + NormalDay + strZoomColumnRow
+ pixelCnt
+ png8
+ "?app_id=" + ApplicationId
+ "&app_code=" + ApplicationCode;
return rqs;
}
}
/res/layout/activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.androidhererestmapimage.MainActivity" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:autoLink="web"
android:text="http://android-er.blogspot.com/"
android:textStyle="bold" />
<SeekBar
android:id="@+id/sbzoom"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:max="13"
android:progress="5" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<LinearLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:layout_margin="5dp"
android:orientation="vertical" >
<TextView
android:id="@+id/maprqs512"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<ImageView
android:id="@+id/mapimage1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
<LinearLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:layout_margin="5dp"
android:orientation="vertical" >
<TextView
android:id="@+id/maprqs256"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<ImageView
android:id="@+id/mapimage2"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
uses-permission of "android.permission.INTERNET" is needed in AndroidManifest.xml.
Download the files.~ More examples of using Here Map REST API on Android
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