我正在尝试开发一个具有按钮的应用程序，单击该按钮应将我带到地图中的当前位置。我的主要困惑是 OnClick 侦听器和地图事件。我哪里可能出错？
这是我的代码：-
package geopoint.ns;
import java.io.IOException;
import java.util.List;
import java.util.Locale;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Point;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapController;
import com.google.android.maps.MapView;
public class GeoPointActivity extends MapActivity {
MapView mapView;
MapController mc;
GeoPoint p;
TextView tvlat,tvlong;
protected LocationManager locationManager;
private static final long MINIMUM_DISTANCE_CHANGE_FOR_UPDATES = 1; // in Meters
private static final long MINIMUM_TIME_BETWEEN_UPDATES = 1000; // in Milliseconds
Button button;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mapView = (MapView) findViewById(R.id.mapView);
mapView.setBuiltInZoomControls(true);
//mapView.displayZoomControls(true);
mapView.setStreetView(false);
mapView.setSatellite(false);
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MINIMUM_TIME_BETWEEN_UPDATES,
MINIMUM_DISTANCE_CHANGE_FOR_UPDATES,
new MyLocationListener()
);
tvlat = (TextView) findViewById(R.layout.main);
tvlong = (TextView) findViewById(R.layout.main);
mc = mapView.getController();
addListenerOnButton();
}
public void addListenerOnButton() {
button = (Button) findViewById(R.id.button1);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
getLoc();
}
});
}
@Override
protected boolean isRouteDisplayed() {
return false;
}
class MapOverlay extends com.google.android.maps.Overlay implements OnClickListener
{
@Override
public boolean draw(Canvas canvas, MapView mapView,
boolean shadow, long when)
{
super.draw(canvas, mapView, shadow);
//---translate the GeoPoint to screen pixels---
Point screenPts = new Point();
mapView.getProjection().toPixels(p, screenPts);
return true;
}
@Override
public boolean onTouchEvent(MotionEvent event, MapView mapView)
{
//---when user lifts his finger---
if (event.getAction() == 1) {
GeoPoint p = mapView.getProjection().fromPixels((int) event.getX(),(int) event.getY());
Geocoder geoCoder = new Geocoder(
getBaseContext(), Locale.getDefault());
try
{
List<Address> addresses = geoCoder.getFromLocation(
p.getLatitudeE6()/1E6,
p.getLongitudeE6()/1E6, 1);
String add = "";
if (addresses.size() > 0)
{
for (int i=0; i<addresses.get(0).getMaxAddressLineIndex();
i++)
add += addresses.get(0).getAddressLine(i) + "\n";
}
Toast.makeText(getBaseContext(), add, Toast.LENGTH_SHORT).show();
}
catch (IOException e) {
e.printStackTrace();
}
return true;
//Toast.makeText(getBaseContext(), p.getLatitudeE6() / 1E6 + "," +p.getLongitudeE6() /1E6 ,Toast.LENGTH_SHORT).show();
}
else
return false;
}
@Override
public void onClick(View arg0) {
getLoc();
}
}
protected void getLoc () {
Location location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
double lat = location.getLatitude();
double lng = location.getLongitude();
p = new GeoPoint(
(int) (lat * 1E6),
(int) (lng * 1E6));
mc.animateTo(p);
mc.setZoom(17);
}
public class MyLocationListener implements LocationListener
{
@Override
public void onLocationChanged(Location loc)
{
loc.getLatitude();
loc.getLongitude();
String Text = "My current location is: " +
"Latitud = " + loc.getLatitude() +
"Longitud = " + loc.getLongitude();
Toast.makeText( getApplicationContext(),
Text,
Toast.LENGTH_SHORT).show();
tvlat.setText(""+loc.getLatitude());
tvlong.setText(""+loc.getLongitude());
this.gpsCurrentLocation();
}
public void gpsCurrentLocation()
{
String coordinates[] = {""+tvlat.getText(), ""+tvlong.getText()};
double lat = Double.parseDouble(coordinates[0]);
double lng = Double.parseDouble(coordinates[1]);
GeoPoint p = new GeoPoint(
(int) (lat * 1E6),
(int) (lng * 1E6));
mc.animateTo(p);
mc.setZoom(7);
mapView.invalidate();
}
@Override
public void onProviderDisabled(String provider)
{
Toast.makeText( getApplicationContext(),
"Gps Disabled",
Toast.LENGTH_SHORT ).show();
}
@Override
public void onProviderEnabled(String provider)
{
Toast.makeText( getApplicationContext(),
"Gps Enabled",
Toast.LENGTH_SHORT).show();
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras)
{
}
}
}
在清单文件中，我拥有 GPS（ACCESS_FINE_LOCATION、ACCESS_MOCK_LOCATION 和 ACCESS_COARSE_LOCATION）和 Internet 所需的所有权限。
我的堆栈跟踪：-
05-18 16:26:50.946: W/dalvikvm(381): Unable to resolve superclass of Lgeopoint/ns/GeoPointActivity; (22)
05-18 16:26:51.026: W/dalvikvm(381): Link of class 'Lgeopoint/ns/GeoPointActivity;' failed
05-18 16:26:51.066: D/AndroidRuntime(381): Shutting down VM
05-18 16:26:51.066: W/dalvikvm(381): threadid=1: thread exiting with uncaught exception (group=0x40015560)
05-18 16:26:51.206: E/AndroidRuntime(381): FATAL EXCEPTION: main
05-18 16:26:51.206: E/AndroidRuntime(381): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{geopoint.ns/geopoint.ns.GeoPointActivity}: java.lang.ClassNotFoundException: geopoint.ns.GeoPointActivity in loader dalvik.system.PathClassLoader[/data/app/geopoint.ns-2.apk]
05-18 16:26:51.206: E/AndroidRuntime(381): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1569)
05-18 16:26:51.206: E/AndroidRuntime(381): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
05-18 16:26:51.206: E/AndroidRuntime(381): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
05-18 16:26:51.206: E/AndroidRuntime(381): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
05-18 16:26:51.206: E/AndroidRuntime(381): at android.os.Handler.dispatchMessage(Handler.java:99)
05-18 16:26:51.206: E/AndroidRuntime(381): at android.os.Looper.loop(Looper.java:130)
05-18 16:26:51.206: E/AndroidRuntime(381): at android.app.ActivityThread.main(ActivityThread.java:3683)
05-18 16:26:51.206: E/AndroidRuntime(381): at java.lang.reflect.Method.invokeNative(Native Method)
05-18 16:26:51.206: E/AndroidRuntime(381): at java.lang.reflect.Method.invoke(Method.java:507)
05-18 16:26:51.206: E/AndroidRuntime(381): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
05-18 16:26:51.206: E/AndroidRuntime(381): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
05-18 16:26:51.206: E/AndroidRuntime(381): at dalvik.system.NativeStart.main(Native Method)
05-18 16:26:51.206: E/AndroidRuntime(381): Caused by: java.lang.ClassNotFoundException: geopoint.ns.GeoPointActivity in loader dalvik.system.PathClassLoader[/data/app/geopoint.ns-2.apk]
05-18 16:26:51.206: E/AndroidRuntime(381): at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:240)
05-18 16:26:51.206: E/AndroidRuntime(381): at java.lang.ClassLoader.loadClass(ClassLoader.java:551)
05-18 16:26:51.206: E/AndroidRuntime(381): at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
05-18 16:26:51.206: E/AndroidRuntime(381): at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
05-18 16:26:51.206: E/AndroidRuntime(381): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1561)
05-18 16:26:51.206: E/AndroidRuntime(381): ... 11 more
05-18 16:26:53.815: I/Process(381): Sending signal. PID: 381 SIG: 9
是我在做任何逻辑错误吗？
更新（AndroidManifest.xml）：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="geopoint.ns"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="10" />
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:name=".GeoPointActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
布局xml文件： http: //pastebin.com/q176i5d2