我制作了一个 android 应用程序，它有助于在 A-GPS 的帮助下找到 GPS 位置，从设置中打开 GPS 后，我想运行进度对话框，直到纬度和经度大于零。我是新手，我编写了以下无法正常工作的代码。任何帮助将不胜感激
谢谢
package com.example.gpsutility;
import android.os.Bundle;
import android.app.Activity;
import android.app.ProgressDialog;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class GPSActivity extends Activity implements OnClickListener {
Button search,exit;
TextView location_tv;
GpsService gps;
ProgressDialog progressDialog = null;
double latitude,longitude;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_gps);
search = (Button)findViewById(R.id.search_button);
exit = (Button)findViewById(R.id.exit_button);
location_tv =(TextView)findViewById(R.id.textview2);
gps = new GpsService(this);
search.setOnClickListener(this);
exit.setOnClickListener(this);
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(v==search)
{
progressDialog = ProgressDialog.show(this, "", "getting location...", true);
new Thread(new Runnable() {
public void run() {
runOnUiThread(new Runnable() {
public void run() {
if(latitude<=0 && longitude<=0)
{
do{
latitude =gps.getLatitude();
longitude = gps.getLongitude();
// location_tv.setText("Location is -\nLat: "+latitude+ "\nLong: "+longitude );
}while(latitude<=0 && longitude<=0);
location_tv.setText(" Location is-\nLat:"+latitude+"\nLong: "+longitude );
progressDialog.dismiss();
}else{
location_tv.setText(" Location is-\nLat:"+latitude+"\nLong: "+longitude );
Log.e("latlong", latitude + ""+longitude);
progressDialog.dismiss();
}
}
});
}
}).start(); }
if(v==exit)
{
finish();
}
}
}
我使用的 GPS SERVICE 类是
package com.example.gpsutility;
public class GpsService extends Service implements LocationListener {
private final Context mContext;
boolean isGPSEnabled = false;
boolean isNetworkEnabled = false;
boolean canGetLocation = false;
Location location;
double latitude;
double longitude;
public static final long MIN_DISTANCE_CHANGE_FOR_UPDATES=10;
public static final long MIN_TIME_BW_UPDATES=1000*60*1;
protected LocationManager locationManager;
public GpsService(Context context)
{
this.mContext=context;
getLocation();
}
@Override
public void onLocationChanged(Location location) {
// TODO Auto-generated method stub
}
@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
@Override
public IBinder onBind(Intent arg0) {
// TODO Auto-generated method stub
return null;
}
public Location getLocation()
{
try {
locationManager =(LocationManager)
mContext.getSystemService(LOCATION_SERVICE); isGPSEnabled=locationManager.isProviderEnabled(locationManager.GPS_PROVIDER);
isNetworkEnabled = locationManager.isProviderEnabled(locationManager.NETWORK_PROVIDER);
if(!isGPSEnabled || !isNetworkEnabled)
{
showSettingsAlert();
}
else {
this.canGetLocation=true;
if(isNetworkEnabled)
{
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("Network", "Network");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
if (isGPSEnabled) {
if (location == null) {
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return location;
}
public double getLatitude(){
if(location != null){
latitude = location.getLatitude();
}
// return latitude
return latitude;
}
/**
* Function to get longitude
* */
public double getLongitude(){
if(location != null){
longitude = location.getLongitude();
}
// return longitude
return longitude;
}
public boolean canGetLocation() {
return this.canGetLocation;
}
public void showSettingsAlert(){
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
// Setting Dialog Title
alertDialog.setTitle("GPS settings");
// Setting Dialog Message
alertDialog.setMessage("GPS is not enabled. Do you want to go to settings menu?");
// Setting Icon to Dialog
//alertDialog.setIcon(R.drawable.delete);
// On pressing Settings button
alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int which) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
}
});
// on pressing cancel button
alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
}
}