在这里，我想首先检查 gps 是否启用，如果 gps 启用，然后在谷歌地图上显示用户位置，检查 gps 是否启用，但它没有打开谷歌地图的类，它们是 MainActivity 类中的一些问题。这是我的代码
gpsactivator.java
package com.example.googlemaps;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.location.LocationManager;
import android.os.AsyncTask;
import android.os.Bundle;
import android.provider.Settings;
import android.util.Log;
import android.widget.Toast;
import com.google.android.gms.maps.MapView;
import com.google.android.maps.MapController;
public class Gpsactivator extends Activity {
Boolean enable = false;
LocationManager locationManager;
int x = 0;
private MapView mapView;
private MapController mapController;
//Provider gpsprovider;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
String provider = Settings.Secure.getString(getContentResolver(), Settings.Secure.LOCATION_PROVIDERS_ALLOWED);
// gpsprovider=LocationManager.GPS_PROVIDER;
if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)){
Toast.makeText(this, "GPS is Enabled in your devide", Toast.LENGTH_SHORT).show();
startActivity(new Intent(this,MainActivity.class));
}else
{
showGPSDisabledAlertToUser();
new ultimate().execute("");
//Toast.makeText(this, "GPS is now Enabled in your devide", Toast.LENGTH_SHORT).show();
//
// ProgressDialog dialog = ProgressDialog.show(Gpsactivator.this, "", "Loading. Please wait...", true);
// while(!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER))
// {
// Log.e("TAG",status.toString() );
// if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER))
// {
// startActivity(new Intent(this,MainActivity.class));
// // dialog.dismiss();
// break;
// }
// }
}
}
private void showGPSDisabledAlertToUser(){
// Toast.makeText(this, "Enabled your Gps and restart your app", Toast.LENGTH_SHORT).show();
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
alertDialogBuilder.setMessage("GPS is disabled in your device. Would you like to enable it?")
.setCancelable(false)
.setPositiveButton("Goto Settings Page To Enable GPS",
new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int id){
Intent callGPSSettingIntent = new Intent(
android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(callGPSSettingIntent);
}
}
);
alertDialogBuilder.setNegativeButton("Cancel",
new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int id){
dialog.cancel();
}
});
AlertDialog alert = alertDialogBuilder.create();
alert.show();
}
private class ultimate extends AsyncTask<String,Void ,Integer> {
@Override
protected Integer doInBackground(String... params) {
// TODO Auto-generated method stub
Boolean status=locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
Log.e("TAAAG",status.toString()+"1" );
while(!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER))
{
Log.e("TAG",status.toString() );
if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER))
{
startActivity(new Intent(Gpsactivator.this,MainActivity.class));
// dialog.dismiss();
break;
}
}
return null;
}
}
@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
finish();
}
}
Mainactivity.java
package com.example.googlemaps;
import java.io.IOException;
import java.util.List;
import java.util.Locale;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
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.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;
import com.google.android.maps.Overlay;
//public class MainActivity extends FragmentActivity {
//
//
// private GoogleMap mMap;
//
//
// @Override
// protected void onCreate(Bundle savedInstanceState) {
// super.onCreate(savedInstanceState);
// setContentView(R.layout.activity_main);
//
// // mMap = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();
// setUpMapIfNeeded();
// }
// private void setUpMapIfNeeded() {
// // Do a null check to confirm that we have not already instantiated the map.
// if (mMap == null) {
// mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)).getMap();
// // Check if we were successful in obtaining the map.
// if (mMap != null) {
// // The Map is verified. It is now safe to manipulate the map.
//
// }
// }
// }
//}
public class MainActivity extends MapActivity {
private MapView mapView;
private MapController mapController;
private LocationManager locationManager;
private LocationListener locationListener;
@SuppressWarnings("deprecation")
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationListener = new GPSLocationListener();
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
0,
0,
locationListener);
mapView = (MapView) findViewById(R.id.mapView);
// enable Street view by default
mapView.setStreetView(true);
// enable to show Satellite view
// mapView.setSatellite(true);
// enable to show Traffic on map
// mapView.setTraffic(true);
mapView.setBuiltInZoomControls(true);
mapController = mapView.getController();
mapController.setZoom(16);
}
@Override
protected boolean isRouteDisplayed() {
return false;
}
private class GPSLocationListener implements LocationListener
{
@Override
public void onLocationChanged(Location location) {
if (location != null) {
GeoPoint point = new GeoPoint(
(int) (location.getLatitude() * 1E6),
(int) (location.getLongitude() * 1E6));
/* Toast.makeText(getBaseContext(),
"Latitude: " + location.getLatitude() +
" Longitude: " + location.getLongitude(),
Toast.LENGTH_SHORT).show();*/
mapController.animateTo(point);
mapController.setZoom(16);
// add marker
MapOverlay mapOverlay = new MapOverlay();
mapOverlay.setPointToDraw(point);
List<Overlay> listOfOverlays = mapView.getOverlays();
listOfOverlays.clear();
listOfOverlays.add(mapOverlay);
String address = ConvertPointToLocation(point);
Toast.makeText(getBaseContext(), address, Toast.LENGTH_SHORT).show();
mapView.invalidate();
}
}
public String ConvertPointToLocation(GeoPoint point) {
String address = "";
Geocoder geoCoder = new Geocoder(
getBaseContext(), Locale.getDefault());
try {
List<Address> addresses = geoCoder.getFromLocation(
point.getLatitudeE6() / 1E6,
point.getLongitudeE6() / 1E6, 1);
if (addresses.size() > 0) {
for (int index = 0; index < addresses.get(0).getMaxAddressLineIndex(); index++)
address += addresses.get(0).getAddressLine(index) + " ";
}
}
catch (IOException e) {
e.printStackTrace();
}
return address;
}
@Override
public void onProviderDisabled(String provider) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
}
class MapOverlay extends Overlay
{
private GeoPoint pointToDraw;
public void setPointToDraw(GeoPoint point) {
pointToDraw = point;
}
public GeoPoint getPointToDraw() {
return pointToDraw;
}
@Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when) {
super.draw(canvas, mapView, shadow);
// convert point to pixels
Point screenPts = new Point();
mapView.getProjection().toPixels(pointToDraw, screenPts);
// add marker
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.red);
canvas.drawBitmap(bmp, screenPts.x, screenPts.y - 24, null); // 24 is the height of image
return true;
}
}
}
日志文件
07-26 17:20:18.145: W/dalvikvm(15108): Unable to resolve superclass of Lcom/example/googlemaps/MainActivity; (1197)
07-26 17:20:18.145: W/dalvikvm(15108): Link of class 'Lcom/example/googlemaps/MainActivity;' failed
07-26 17:20:18.145: E/dalvikvm(15108): Could not find class 'com.example.googlemaps.MainActivity', referenced from method com.example.googlemaps.Gpsactivator.onCreate
07-26 17:20:18.145: W/dalvikvm(15108): VFY: unable to resolve const-class 591 (Lcom/example/googlemaps/MainActivity;) in Lcom/example/googlemaps/Gpsactivator;
07-26 17:20:18.145: D/dalvikvm(15108): VFY: replacing opcode 0x1c at 0x0033
07-26 17:20:18.145: D/dalvikvm(15108): VFY: dead code 0x0035-003a in Lcom/example/googlemaps/Gpsactivator;.onCreate (Landroid/os/Bundle;)V
07-26 17:20:18.145: I/ApplicationPackageManager(15108): cscCountry is not German : INS
07-26 17:20:19.036: D/AndroidRuntime(15108): Shutting down VM
07-26 17:20:19.036: W/dalvikvm(15108): threadid=1: thread exiting with uncaught exception (group=0x40018578)
07-26 17:20:19.731: E/AndroidRuntime(15108): FATAL EXCEPTION: main
07-26 17:20:19.731: E/AndroidRuntime(15108): java.lang.NoClassDefFoundError: com.example.googlemaps.MainActivity
07-26 17:20:19.731: E/AndroidRuntime(15108): at com.example.googlemaps.Gpsactivator.onCreate(Gpsactivator.java:37)
07-26 17:20:19.731: E/AndroidRuntime(15108): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
07-26 17:20:19.731: E/AndroidRuntime(15108): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
07-26 17:20:19.731: E/AndroidRuntime(15108): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
07-26 17:20:19.731: E/AndroidRuntime(15108): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
07-26 17:20:19.731: E/AndroidRuntime(15108): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
07-26 17:20:19.731: E/AndroidRuntime(15108): at android.os.Handler.dispatchMessage(Handler.java:99)
07-26 17:20:19.731: E/AndroidRuntime(15108): at android.os.Looper.loop(Looper.java:130)
07-26 17:20:19.731: E/AndroidRuntime(15108): at android.app.ActivityThread.main(ActivityThread.java:3687)
07-26 17:20:19.731: E/AndroidRuntime(15108): at java.lang.reflect.Method.invokeNative(Native Method)
07-26 17:20:19.731: E/AndroidRuntime(15108): at java.lang.reflect.Method.invoke(Method.java:507)
07-26 17:20:19.731: E/AndroidRuntime(15108): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
07-26 17:20:19.731: E/AndroidRuntime(15108): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
07-26 17:20:19.731: E/AndroidRuntime(15108): at dalvik.system.NativeStart.main(Native Method)