I'm working to implement MapView for the given gpx file to show way points and tracks,please any one guide me to implement it with sample code.
Thanks in advance.
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问题:
回答1:
It is working correctly
package com.lightcone.mapoverlaydemo;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.List;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserFactory;
import android.graphics.drawable.Drawable;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.KeyEvent;
import android.view.View;
import android.view.Window;
import android.view.View.OnClickListener;
import android.widget.Button;
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.OverlayItem;
public class ShowTheMap extends MapActivity {
private static double lat;
private static double lon;
private int latE6;
private int lonE6;
private MapController mapControl;
private GeoPoint gp;
private MapView mapView;
private Button overlayButton, accessButton;
private Button routeButton;
private List<Overlay> mapOverlays;
private Drawable drawable1, drawable2;
private MyItemizedOverlay itemizedOverlay1, itemizedOverlay2;
private boolean foodIsDisplayed = false;
// Define an array containing the food overlay items
private OverlayItem[] foodItem = {
new OverlayItem(new GeoPoint(35952967, -83929158), "Food Title 1",
"Food snippet 1"),
new OverlayItem(new GeoPoint(35953000, -83928000), "Food Title 2",
"Food snippet 2"),
new OverlayItem(new GeoPoint(35955000, -83929158), "Food Title 3",
"Food snippet 3") };
// Define an array containing the access overlay items
private OverlayItem[] accessItem = {
new OverlayItem(new GeoPoint(35953700, -83926158),
"Access Title 1", "Access snippet 1"),
new OverlayItem(new GeoPoint(35954000, -83928200),
"Access Title 2", "Access snippet 2"),
new OverlayItem(new GeoPoint(35955000, -83927558),
"Access Title 3", "Access snippet 3"),
new OverlayItem(new GeoPoint(35954000, -83927158),
"Access Title 4", "Access snippet 4") };
String TAG = "GPStest";
// Set up the array of GeoPoints defining the route
int numberRoutePoints;
GeoPoint routePoints[]; // Dimension will be set in class RouteLoader below
int routeGrade[]; // Index for slope of route from point i to point i+1
RouteSegmentOverlay route; // This will hold the route segments
boolean routeIsDisplayed = false;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE); // Suppress title bar for
// more space
setContentView(R.layout.showthemap);
// Add map controller with zoom controls
mapView = (MapView) findViewById(R.id.mv);
mapView.setSatellite(false);
mapView.setTraffic(false);
mapView.setBuiltInZoomControls(true); // Set android:clickable=true in
// main.xml
int maxZoom = mapView.getMaxZoomLevel();
int initZoom = maxZoom - 2;
mapControl = mapView.getController();
mapControl.setZoom(initZoom);
// Convert lat/long in degrees into integers in microdegrees
latE6 = (int) (35.955 * 1e6);
lonE6 = (int) (-83.9265 * 1e6);
gp = new GeoPoint(latE6, lonE6);
mapControl.animateTo(gp);
// // Button to control food overlay
// overlayButton = (Button)findViewById(R.id.doOverlay);
// overlayButton.setOnClickListener(new OnClickListener(){
// public void onClick(View v) {
// setOverlay1();
// }
// });
//
// // Button to control access overlay
// accessButton = (Button)findViewById(R.id.doAccess);
// accessButton.setOnClickListener(new OnClickListener(){
// public void onClick(View v) {
// setOverlay2();
// }
// });
// Button to control route overlay
routeButton = (Button) findViewById(R.id.doRoute);
routeButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
if (!routeIsDisplayed) {
routeIsDisplayed = true;
loadRouteData();
} else {
if (route != null)
route.setRouteView(false);
route = null; // To prevent multiple route instances if key
// toggled rapidly (see line 235)
routeIsDisplayed = false;
mapView.postInvalidate();
}
}
});
}
/*
* Methods to set map overlays. In this case we will place a small overlay
* image at a specified location. Place the marker image as a png file in
* res > drawable-* . For example, the reference to
* R.drawable.knifefork_small below is to an image file called
* knifefork_small.png in the project folder res > drawable-hdpi. Can only
* use lower case letters a-z, numbers 0-9, ., and _ in these image file
* names. In this example the single overlay item is specified by drawable
* and the location of the overlay item is specified by overlayitem.
*/
// Display food location overlay. If not already displayed, clicking button
// displays all
// food overlays. If already displayed successive clicks remove items one by
// one. This
// illustrates ability to change individual overlay items dynamically at
// runtime.
public void setOverlay1() {
int foodLength = foodItem.length;
// Create itemizedOverlay2 if it doesn't exist and display all three
// items
if (!foodIsDisplayed) {
mapOverlays = mapView.getOverlays();
drawable1 = this.getResources().getDrawable(
R.drawable.knifefork_small);
itemizedOverlay1 = new MyItemizedOverlay(drawable1);
// Display all three items at once
for (int i = 0; i < foodLength; i++) {
itemizedOverlay1.addOverlay(foodItem[i]);
}
mapOverlays.add(itemizedOverlay1);
foodIsDisplayed = !foodIsDisplayed;
// Remove each item successively with button clicks
} else {
itemizedOverlay1.removeItem(itemizedOverlay1.size() - 1);
if ((itemizedOverlay1.size() < 1))
foodIsDisplayed = false;
}
// Added symbols will be displayed when map is redrawn so force redraw
// now
mapView.postInvalidate();
}
// Display accessibility overlay. If not already displayed, successive
// button clicks display each of
// the three icons successively, then the next removes them all. This
// illustrates the ability to
// change individual overlay items dynamically at runtime.
public void setOverlay2() {
int accessLength = accessItem.length;
// Create itemizedOverlay2 if it doesn't exist
if (itemizedOverlay2 == null) {
mapOverlays = mapView.getOverlays();
drawable2 = this.getResources().getDrawable(
R.drawable.accessibility);
itemizedOverlay2 = new MyItemizedOverlay(drawable2);
}
// Add items with each click
if (itemizedOverlay2.size() < accessLength) {
itemizedOverlay2.addOverlay(accessItem[itemizedOverlay2.size()]);
mapOverlays.add(itemizedOverlay2);
// Remove all items with one click
} else {
for (int i = 0; i < accessLength; i++) {
itemizedOverlay2.removeItem(accessLength - 1 - i);
}
}
// Added symbols will be displayed when map is redrawn so force redraw
// now
mapView.postInvalidate();
}
// Method to insert latitude and longitude in degrees
public static void putLatLong(double latitude, double longitude) {
lat = latitude;
lon = longitude;
}
// This sets the s key on the phone to toggle between satellite and map view
// and the t key to toggle between traffic and no traffic view (traffic view
// relevant only in urban areas where it is reported).
public boolean onKeyDown(int keyCode, KeyEvent e) {
if (keyCode == KeyEvent.KEYCODE_S) {
mapView.setSatellite(!mapView.isSatellite());
return true;
} else if (keyCode == KeyEvent.KEYCODE_T) {
mapView.setTraffic(!mapView.isTraffic());
mapControl.animateTo(gp); // To ensure change displays immediately
}
return (super.onKeyDown(keyCode, e));
}
// Required method since class extends MapActivity
@Override
protected boolean isRouteDisplayed() {
return false; // Don't display a route
}
// Method to read route data from server as XML
public void loadRouteData() {
try {
String url = "http://eagle.phys.utk.edu/reubendb/UTRoute.php";
String data = "?lat1=35952967&lon1=-83929158&lat2=35956567&lon2=-83925450";
// RouteLoader RL = new RouteLoader();
// RL.execute(new URL(url+data));
new RouteLoader().execute(new URL(url + data));
} catch (MalformedURLException e) {
Log.i("NETWORK", "Failed to generate valid URL");
}
}
// Overlay a route. This method is only executed after loadRouteData()
// completes
// on background thread.
public void overlayRoute() {
if (route != null)
return; // To prevent multiple route instances if key toggled
// rapidly (see also line 116)
// Set up the overlay controller
route = new RouteSegmentOverlay(routePoints, routeGrade); // My class
// defining
// route
// overlay
mapOverlays = mapView.getOverlays();
mapOverlays.add(route);
// Added symbols will be displayed when map is redrawn so force redraw
// now
mapView.postInvalidate();
}
/*
* Class to implement single task on background thread without having to
* manage the threads directly. Launch with
* "new RouteLoader().execute(new URL(urlString)". Must be launched from the
* UI thread and may only be invoked once. Adapted from example in Ch. 10 of
* Android Wireless Application Development. Use this to do data load from
* network on separate thread from main user interface to prevent locking
* main UI if there is network delay.
*/
private class RouteLoader extends AsyncTask<URL, String, String> {
@Override
protected String doInBackground(URL... params) {
// This pattern takes more than one param but we'll just use the
// first
try {
URL text = params[0];
XmlPullParserFactory parserCreator;
parserCreator = XmlPullParserFactory.newInstance();
XmlPullParser parser = parserCreator.newPullParser();
// parser.setInput(text.openStream(), null);
parser.setInput(getResources()
.openRawResource(R.raw.fells_loop), null);
publishProgress("Parsing XML...");
int parserEvent = parser.getEventType();
int pointCounter = -1;
int wptCounter = -1;
int totalWaypoints = -1;
int lat = -1;
int lon = -1;
String wptDescription = "";
int grade = -1;
// Parse the XML returned on the network
while (parserEvent != XmlPullParser.END_DOCUMENT) {
switch (parserEvent) {
case XmlPullParser.START_TAG:
String tag = parser.getName();
if (tag.compareTo("number") == 0) {
numberRoutePoints = Integer.parseInt(parser
.getAttributeValue(null, "numpoints"));
totalWaypoints = Integer.parseInt(parser
.getAttributeValue(null, "numwpts"));
routePoints = new GeoPoint[numberRoutePoints];
routeGrade = new int[numberRoutePoints];
Log.i(TAG, " Total points = " + numberRoutePoints
+ " Total waypoints = " + totalWaypoints);
}
if (tag.compareTo("trkpt") == 0) {
pointCounter++;
lat = Integer.parseInt(parser.getAttributeValue(
null, "lat"));
lon = Integer.parseInt(parser.getAttributeValue(
null, "lon"));
grade = Integer.parseInt(parser.getAttributeValue(
null, "grade"));
routePoints[pointCounter] = new GeoPoint(lat, lon);
routeGrade[pointCounter] = grade;
Log.i(TAG, " trackpoint=" + pointCounter
+ " latitude=" + lat + " longitude=" + lon
+ " grade=" + grade);
} else if (tag.compareTo("wpt") == 0) {
wptCounter++;
lat = Integer.parseInt(parser.getAttributeValue(
null, "lat"));
lon = Integer.parseInt(parser.getAttributeValue(
null, "lon"));
wptDescription = parser.getAttributeValue(null,
"description");
Log.i(TAG, " waypoint=" + wptCounter
+ " latitude=" + lat + " longitude=" + lon
+ " " + wptDescription);
}
break;
}
parserEvent = parser.next();
}
} catch (Exception e) {
Log.i("RouteLoader", "Failed in parsing XML", e);
return "Finished with failure.";
}
return "Done...";
}
protected void onCancelled() {
Log.i("RouteLoader", "GetRoute task Cancelled");
}
// Now that route data are loaded, execute the method to overlay the
// route on the map
protected void onPostExecute(String result) {
Log.i(TAG, "Route data transfer complete");
overlayRoute();
}
protected void onPreExecute() {
Log.i(TAG, "Ready to load URL");
}
protected void onProgressUpdate(String... values) {
super.onProgressUpdate(values);
}
}
}
feel_loop.xml file content from raw folder
<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<gpx
version="1.0"
creator="ExpertGPS 1.1.1 - http://www.topografix.com"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.topografix.com/GPX/1/0"
xmlns:topografix="http://www.topografix.com/GPX/Private/TopoGrafix/0/1"
xsi:schemaLocation="http://www.topografix.com/GPX/1/0 http://www.topografix.com/GPX/1/0/gpx.xsd http://www.topografix.com/GPX/Private/TopoGrafix/0/1 http://www.topografix.com/GPX/Private/TopoGrafix/0/1/topografix.xsd">
<number numpoints="23" numwpts="2"></number>
<wpt lat="35952967" lon="-83929158" description="Construction"></wpt>
<wpt lat="35955038" lon="-83929126" description="Heavy traffic"></wpt>
<trk>
<trkseg>
<trkpt lat="35952967" lon="-83929158" grade="1"></trkpt>
<trkpt lat="35954021" lon="-83930341" grade="1"></trkpt>
<trkpt lat="35954951" lon="-83929075" grade="1"></trkpt>
<trkpt lat="35955038" lon="-83929126" grade="4"></trkpt>
<trkpt lat="35955203" lon="-83928973" grade="1"></trkpt>
<trkpt lat="35955212" lon="-83928855" grade="1"></trkpt>
<trkpt lat="35955603" lon="-83928273" grade="2"></trkpt>
<trkpt lat="35955807" lon="-83928369" grade="1"></trkpt>
<trkpt lat="35955974" lon="-83927943" grade="1"></trkpt>
<trkpt lat="35956063" lon="-83927720" grade="1"></trkpt>
<trkpt lat="35956291" lon="-83927358" grade="1"></trkpt>
<trkpt lat="35956471" lon="-83927229" grade="1"></trkpt>
<trkpt lat="35956541" lon="-83927176" grade="2"></trkpt>
<trkpt lat="35956397" lon="-83927044" grade="3"></trkpt>
<trkpt lat="35956274" lon="-83926685" grade="1"></trkpt>
<trkpt lat="35956213" lon="-83926642" grade="1"></trkpt>
<trkpt lat="35956239" lon="-83926261" grade="1"></trkpt>
<trkpt lat="35956202" lon="-83925722" grade="1"></trkpt>
<trkpt lat="35956226" lon="-83925467" grade="1"></trkpt>
<trkpt lat="35956343" lon="-83925502" grade="1"></trkpt>
<trkpt lat="35956324" lon="-83925617" grade="1"></trkpt>
<trkpt lat="35956445" lon="-83925379" grade="1"></trkpt>
<trkpt lat="35956567" lon="-83925450" grade="1"></trkpt>
</trkseg>
</trk>
</gpx>
回答2:
Building on Kandha's answer, for the actual GPX parsing you can easily use one of the existing libraries to do it. See this other StackOverflow question.
