类型MainActivity没有外围实例是在范围访问 [英] No enclosing instance of the type MainActivity is accessible in scope
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问题描述
我有这样的code，这是我希望得到的 GPS 从 GPSTracker 经纬度类
但错误显示
GPS =新GPSTracker（MainActivity.this）;
gps.getLatitude（）;
类型MainActivity没有外围实例是在范围访问
完整code
BootComplete.java
公共类BootComplete扩展广播接收器{//私有静态最后弦乐preFS_NAME = NULL;
公共静态最后弦乐preFS_NAME =我的preFS
串storedSimSerial;
串currentSimSerial;
字符串电子邮件; //用户的电子邮件地址输入，生成电子邮件，发送到这个地址，
串mobileno; //用户的手机号码输入，产生的短信发送到这个地址
串短信; //生成短信到用户
公共GPSTracker GPS;
@覆盖
公共无效的onReceive（最终上下文的背景下，意图意图）{ 共享preferences preFS = context.getShared preferences（preFS_NAME，0）;
storedSimSerial = prefs.getString（storedSimSerial，）;
mobileno = prefs.getString（trustedNum，）;
电子邮件= prefs.getString（电子邮件，）;
TelephonyManager TM =（TelephonyManager）context.getSystemService（Service.TELEPHONY_SERVICE）;
currentSimSerial = tm.getSimSerialNumber（）; 如果（currentSimSerial！= NULL）{
如果（currentSimSerial.compareToIgnoreCase（storedSimSerial）== 0）{ }其他{ 。preFS = context.getApplicationContext（）getShared preferences（preFS_NAME，0）;
共享preferences.Editor编辑器= prefs.edit（）; GPS =新GPSTracker（MainActivity.this）;
gps.getLatitude（）; 短信=警告！\\ NSIM卡改变\\ NSIM序列号：\\ n+ tm.getSimSerialNumber（）+
\\ n网络：+ tm.getNetworkOperatorName（）+\\ nLatitude：\\ n+ gps.getLatitude（）; editor.putBoolean（SimChangeMail，真正的）;
editor.putString（subjectSimChange，您的SIM卡已经改变了。）;
editor.putString（bodySimChange，辛序列号为：\\ n+ tm.getSimSerialNumber（）+\\ n+
这辛序列号是唯一的，用于识别所有者\\ n网络操作员是：+
tm.getNetworkOperatorName（）+
\\ nThanks使用移动安全应用程序）;
editor.putString（SimChangeSms，短信）;
editor.commit（）; SmsManager SM = SmsManager.getDefault（）;
字符串NUM = mobileno;
sm.sendTextMessage（NUM，空，短信，NULL，NULL）;
}
}其他{ }
}
}
GPSTracker.java
公共类GPSTracker扩展服务实现LocationListener的{ 私人最终上下文mContext; //标志GPS状态
布尔isGPSEnabled = FALSE; //标志网络状态
布尔isNetworkEnabled = FALSE; //标志GPS状态
布尔canGetLocation = FALSE; 地点位置; // 位置
双纬度; //纬度
双经度; //经度 //最小距离改变米的更新
私有静态最后长MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; //10米 //毫秒更新之间的最短时间
私有静态最后长MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1分钟 //声明一个位置管理
受保护的LocationManager的LocationManager; 公共GPSTracker（上下文的背景下）{
this.mContext =背景;
的getLocation（）;
} 公共场所的getLocation（）{
尝试{
的LocationManager =（的LocationManager）mContext
.getSystemService（LOCATION_SERVICE）; //获取GPS状态
isGPSEnabled =的LocationManager
.isProviderEnabled（LocationManager.GPS_PROVIDER）; //获取网络状态
isNetworkEnabled =的LocationManager
.isProviderEnabled（LocationManager.NETWORK_PROVIDER）; 如果（isGPSEnabled＆安培;！＆安培;！isNetworkEnabled）{
//没有启用网络供应商
}其他{
this.canGetLocation = TRUE;
//首先从网络提供商处获取位置
如果（isNetworkEnabled）{
locationManager.requestLocationUpdates（
LocationManager.NETWORK_PROVIDER，
MIN_TIME_BW_UPDATES，
MIN_DISTANCE_CHANGE_FOR_UPDATES，这一点）;
Log.d（网络，网络）;
如果（的LocationManager！= NULL）{
位置=的LocationManager
.getLastKnownLocation（LocationManager.NETWORK_PROVIDER）;
如果（位置！= NULL）{
纬度= location.getLatitude（）;
经度= location.getLongitude（）;
}
}
}
//如果GPS功能的获得纬度/长期使用GPS服务
如果（isGPSEnabled）{
如果（位置== NULL）{
locationManager.requestLocationUpdates（
LocationManager.GPS_PROVIDER，
MIN_TIME_BW_UPDATES，
MIN_DISTANCE_CHANGE_FOR_UPDATES，这一点）;
Log.d（GPS已启用，GPS功能的）;
如果（的LocationManager！= NULL）{
位置=的LocationManager
.getLastKnownLocation（LocationManager.GPS_PROVIDER）;
如果（位置！= NULL）{
纬度= location.getLatitude（）;
经度= location.getLongitude（）;
}
}
}
}
} }赶上（例外五）{
e.printStackTrace（）;
} 返回的位置;
} / **
*停止使用GPS监听器
*调用此函数将停止在你的应用程序中使用GPS
* * /
公共无效stopUsingGPS（）{
如果（的LocationManager！= NULL）{
locationManager.removeUpdates（GPSTracker.this）;
}
} / **
*函数来获取纬度
* * /
公共双getLatitude（）{
如果（位置！= NULL）{
纬度= location.getLatitude（）;
} //返回纬度
返回纬度;
} / **
*函数来获取经度
* * /
公共双getLongitude（）{
如果（位置！= NULL）{
经度= location.getLongitude（）;
} //返回经度
返回经度;
} / **
*功能检查启用GPS / WIFI
* @返回布尔
* * /
公共布尔canGetLocation（）{
返回this.canGetLocation;
} / **
*功能，以显示设置警告对话框
*在pressing设置按钮将劳克设置选项
* * /
公共无效showSettingsAlert（）{
AlertDialog.Builder alertDialog =新AlertDialog.Builder（mContext）; //设置对话框标题
alertDialog.setTitle（GPS是设置）; //设置对话框留言
alertDialog.setMessage（GPS未启用你想要去设置菜单？）; //在pressing设置按钮
alertDialog.setPositiveButton（设置，新DialogInterface.OnClickListener（）{
公共无效的onClick（DialogInterface对话，诠释它）{
意向意图=新意图（Settings.ACTION_LOCATION_SOURCE_SETTINGS）;
mContext.startActivity（意向）;
}
}）; //在pressing取消按钮
alertDialog.setNegativeButton（取消，新DialogInterface.OnClickListener（）{
公共无效的onClick（DialogInterface对话，诠释它）{
dialog.cancel（）;
}
}）; //显示警报信息
alertDialog.show（）;
} @覆盖
公共无效onLocationChanged（地点）{
} @覆盖
公共无效onProviderDisabled（字符串提供商）{
} @覆盖
公共无效onProviderEnabled（字符串提供商）{
} @覆盖
公共无效onStatusChanged（字符串提供商，INT地位，捆绑演员）{
} @覆盖
公众的IBinder onBind（意向为arg0）{
返回null;
}}
解决方案
您只能使用 MainActivity.this 如果BootComplete里面MainActivity一个嵌套类。
作为您GPSTracker只需要一个环境，你可以做
GPS =新GPSTracker（背景）;
I have this code, which i want to get GPS latitude and longitude from GPSTracker class
But the error show
gps=new GPSTracker(MainActivity.this);
gps.getLatitude();
No enclosing instance of the type MainActivity is accessible in scope
The complete code BootComplete.java
public class BootComplete extends BroadcastReceiver{
//private static final String PREFS_NAME = null;
public static final String PREFS_NAME = "MyPrefs";
String storedSimSerial;
String currentSimSerial;
String email; //email address input by user, generate email and sent to this address
String mobileno; //mobile number input by user, generate SMS and send to this address
String sms; //generate sms to user
public GPSTracker gps;
@Override
public void onReceive(final Context context, Intent intent) {
SharedPreferences prefs = context.getSharedPreferences(PREFS_NAME, 0);
storedSimSerial = prefs.getString("storedSimSerial", "");
mobileno = prefs.getString("trustedNum", "");
email = prefs.getString("Email", "");
TelephonyManager tm = (TelephonyManager) context.getSystemService(Service.TELEPHONY_SERVICE);
currentSimSerial = tm.getSimSerialNumber();
if(currentSimSerial != null){
if(currentSimSerial.compareToIgnoreCase(storedSimSerial) == 0){
}else{
prefs = context.getApplicationContext().getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = prefs.edit();
gps=new GPSTracker(MainActivity.this);
gps.getLatitude();
sms = "Alert!!!\nSim card changed.\nSim Serial Number:\n"+tm.getSimSerialNumber()+
"\nNetwork : "+ tm.getNetworkOperatorName()+"\nLatitude:\n" + gps.getLatitude();
editor.putBoolean("SimChangeMail", true);
editor.putString("subjectSimChange", "Your Sim card has changed.");
editor.putString("bodySimChange","Sim Serial Number is :\n"+tm.getSimSerialNumber()+"\n" +
"This Sim serial number is unique and used to identify the owner.\nNetwork Operator is : "+
tm.getNetworkOperatorName()+
"\nThanks for using Mobile Security Application");
editor.putString("SimChangeSms", sms);
editor.commit();
SmsManager sm = SmsManager.getDefault();
String num = mobileno;
sm.sendTextMessage(num, null, sms, null, null);
}
}else{
}
}
}
GPSTracker.java
public class GPSTracker extends Service implements LocationListener {
private final Context mContext;
// flag for GPS status
boolean isGPSEnabled = false;
// flag for network status
boolean isNetworkEnabled = false;
// flag for GPS status
boolean canGetLocation = false;
Location location; // location
double latitude; // latitude
double longitude; // longitude
// The minimum distance to change Updates in meters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters
// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1 minute
// Declaring a Location Manager
protected LocationManager locationManager;
public GPSTracker(Context context) {
this.mContext = context;
getLocation();
}
public Location getLocation() {
try {
locationManager = (LocationManager) mContext
.getSystemService(LOCATION_SERVICE);
// getting GPS status
isGPSEnabled = locationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
// getting network status
isNetworkEnabled = locationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled) {
// no network provider is enabled
} else {
this.canGetLocation = true;
// First get location from Network Provider
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 GPS Enabled get lat/long using GPS Services
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;
}
/**
* Stop using GPS listener
* Calling this function will stop using GPS in your app
* */
public void stopUsingGPS(){
if(locationManager != null){
locationManager.removeUpdates(GPSTracker.this);
}
}
/**
* Function to get latitude
* */
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;
}
/**
* Function to check GPS/wifi enabled
* @return boolean
* */
public boolean canGetLocation() {
return this.canGetLocation;
}
/**
* Function to show settings alert dialog
* On pressing Settings button will lauch Settings Options
* */
public void showSettingsAlert(){
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
// Setting Dialog Title
alertDialog.setTitle("GPS is settings");
// Setting Dialog Message
alertDialog.setMessage("GPS is not enabled. Do you want to go to settings menu?");
// 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();
}
@Override
public void onLocationChanged(Location location) {
}
@Override
public void onProviderDisabled(String provider) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public IBinder onBind(Intent arg0) {
return null;
}
}
解决方案
you can only use MainActivity.this if BootComplete is a nested class inside MainActivity.
as your GPSTracker only needs a context, you can do
gps = new GPSTracker(context);
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