我试图在应用程序启动时获取用户的 GPS/GeoLocation,但有时它会导致应用程序 UI 没有响应,然后著名的 Android 提示应用程序没有响应!所以我决定尝试 AsyncTask 来获取用户在主活动中的位置信息;但有时 UI 仍会挂起(通常是在禁用 gps 设置时,所以我转到系统设置以启用它,当我按下返回以返回我的应用程序时,它变得如此缓慢/无响应。)那我在这里做错了什么?任何帮助表示赞赏。
我应该获取位置信息的网络类:
package com.parspake.kookojapost;
import android.content.Context;
import android.location.*;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.os.Looper;
import android.util.Log;
import android.widget.Toast;
import java.io.IOException;
import java.util.List;
import java.util.Locale;
public class ConnectionHandler {
private Context ctx;
double mLat;
double mLong;
String currCity;
String currCountry;
String mAddress;
LocationManager currentLoc;
LocationListener locLis;
public ConnectionHandler(Context context) {
this.ctx = context;
}
public boolean internetAccess() {
ConnectivityManager con = (ConnectivityManager) ctx.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = con.getActiveNetworkInfo();
// Simplified: return netInfo != null && netInfo.isConnected();
if (netInfo != null && netInfo.isConnected()) {
return true;
} else {
return false;
}
}
public boolean locationSourceEnabled() {
currentLoc = (LocationManager) ctx.getSystemService(Context.LOCATION_SERVICE);
boolean isInternetLocationAvailable = currentLoc.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
boolean isGpsAvailable = currentLoc.isProviderEnabled(LocationManager.GPS_PROVIDER);
if (isInternetLocationAvailable) {
Log.d("kookojaPost", "internet location avaiable");
return true;
} else if (isGpsAvailable) {
Log.d("kookojaPost", "gps location avaiable");
return true;
}
return false;
}
public void getLocation() {
locLis = new LocationListener() {
@Override
public void onLocationChanged(Location location) {
Geocoder gcd = new Geocoder(ctx, Locale.getDefault());
List<Address> addresses;
try {
addresses = gcd.getFromLocation(location.getLatitude(), location.getLongitude(), 1);
if (addresses.size() > 0) {
currCity = addresses.get(0).getLocality();
currCountry = addresses.get(0).getCountryName();
mAddress = currCity + " - " + currCountry;
}
} catch (IOException e) {
// e.printStackTrace();
Log.d("kookojaPost", e.getMessage());
}
String s = "Loction: \n" + mAddress;
Toast.makeText(ctx, s, Toast.LENGTH_LONG).show();
Toast.makeText(ctx, "Location GPS: " + location.getLatitude() + " - " + location.getLongitude(), Toast.LENGTH_LONG).show();
mLat = location.getLatitude();
mLong = location.getLongitude();
}
@Override
public void onStatusChanged(String s, int i, Bundle bundle) {
}
@Override
public void onProviderEnabled(String s) {
}
@Override
public void onProviderDisabled(String s) {
}
};
currentLoc = (LocationManager) ctx.getSystemService(Context.LOCATION_SERVICE);
if (locationSourceEnabled()) {
if (currentLoc.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
currentLoc.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 10000, 50, locLis, Looper.getMainLooper());
}
if (currentLoc.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
currentLoc.requestLocationUpdates(LocationManager.GPS_PROVIDER, 10000, 50, locLis, Looper.getMainLooper());
}
}
}
}
这是我的主要活动,我在这里使用 AsyncTask 来做背景工作,这显然没有做它应该做的事情!
package com.parspake.kookojapost;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.location.Location;
import android.media.ThumbnailUtils;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Environment;
import android.preference.PreferenceManager;
import android.provider.MediaStore;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.Toast;
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Calendar;
public class MainAct extends Activity {
ProgressBar pg;
ConnectionHandler mNet;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
pg = (ProgressBar) findViewById(R.id.progressBar);
mNet = new ConnectionHandler(this);
// pg.setIndeterminate(true);
// pg.setVisibility(View.VISIBLE);
// new FetchLocation().execute();
}
@Override
protected void onResume() {
super.onResume();
new FetchLocation().execute();
}
private class FetchLocation extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pg.setVisibility(View.VISIBLE);
}
@Override
protected Void doInBackground(Void... params) {
if (mNet.locationSourceEnabled()) {
Log.d("kookojaPost","mLat is: " + mNet.mLat);
// while (mNet.mLat == 0.0) {
// mNet.getLocation();
// }
if (mNet.mLat == 0.0) {
mNet.getLocation();
}
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
pg.setVisibility(View.INVISIBLE);
}
}
}