我正在使用一个SMSReceiver类来接收短信，然后将短信作为额外信息发送到我的主要活动，以便在地图应用程序中使用。在我的onReceive方法中，我提供额外的东西，我得到的值非常好，但是当我尝试使用变量稍后我的代码反转geoCode从地址获取坐标然后突然全局变量再次为null：（
该方法在第324行被称为showOnMapClicked，其中变量再次为null。
短信从DDMS发送。
有人请求帮助，我无法弄明白！
OnReceive Class：
package com.example.maps;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.os.Bundle;
import android.telephony.SmsMessage;
import android.widget.Toast;
import android.content.Intent;
public class SMSReceiver extends BroadcastReceiver
{
@Override
public void onReceive(Context context, Intent intent)
{
//Adding bundle extras to be used by the main class
Bundle bundle = intent.getExtras();
SmsMessage[] msgs = null;
String str = "SMS from ";
//Adding the sms to the array to be stored
if (bundle != null)
{
Object[] pdus = (Object[]) bundle.get("pdus");
msgs = new SmsMessage[pdus.length];
for (int i = 0; i < msgs.length; i++) {
msgs[i] = SmsMessage.createFromPdu((byte[])pdus[i]);
if (i == 0)
{
//Appending the information to the string to be displayed
str += msgs[i].getOriginatingAddress();
str += ": \n";
}
str += msgs[i].getMessageBody().toString();
}
Toast.makeText(context, str, Toast.LENGTH_LONG).show();
//Creating the new intent
Intent mainActivityIntent = new Intent(context, MainActivity.class);
mainActivityIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(mainActivityIntent);
//Making the intent broadcast to the main class and putting the extra in to be displayed
Intent broadcastIntent = new Intent();
broadcastIntent.setAction("SMS_RECEIVED_ACTION");
//Setting the name of the string to "sms"
broadcastIntent.putExtra("sms", str);
context.sendBroadcast(broadcastIntent);
//Stops the sms from going directly into the inbox
this.abortBroadcast();
}
}
}
主要活动类：
package com.example.maps;
//Daniel Tromp - Assignment 2 - 12002076
//Imports for DAYS!
import java.io.IOException;
import java.util.List;
import java.util.Locale;
import com.example.maps.R;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesClient;
import com.google.android.gms.location.LocationClient;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.model.LatLng;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentFilter;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.os.AsyncTask;
import android.os.Bundle;
import android.telephony.SmsManager;
import android.text.InputFilter;
import android.text.InputType;
import android.text.method.DigitsKeyListener;
import android.util.Log;
import android.view.View;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
//Implementing all the needed services
public class MainActivity extends Activity implements
GooglePlayServicesClient.ConnectionCallbacks,
GooglePlayServicesClient.OnConnectionFailedListener, LocationListener {
// Initializing the needed globals
Location mLocation;
String addressSms;
String addressText;
public GoogleMap mMap;
private TextView mAddress;
private ProgressBar mActivityIndicator;
private LocationClient mLocationClient;
BroadcastReceiver smsSentReceiver, smsDeliveredReceiver;
IntentFilter intentFilter;
// Milliseconds per second
private static final int MILLISECONDS_PER_SECOND = 1000;
// Update frequency in seconds
public static final int UPDATE_INTERVAL_IN_SECONDS = 5;
// Update frequency in milliseconds
private static final long UPDATE_INTERVAL = MILLISECONDS_PER_SECOND
* UPDATE_INTERVAL_IN_SECONDS;
// The fastest update frequency, in seconds
private static final int FASTEST_INTERVAL_IN_SECONDS = 1;
// A fast frequency ceiling in milliseconds
private static final long FASTEST_INTERVAL = MILLISECONDS_PER_SECOND
* FASTEST_INTERVAL_IN_SECONDS;
// Define an object that holds accuracy and frequency parameters
private LocationRequest mLocationRequest;
private BroadcastReceiver intentReceiver = new BroadcastReceiver() {
@Override
//On receiving a message, the textview is set to the sms message
public void onReceive(Context context, Intent intent) {
addressSms = intent.getStringExtra("sms");
//Toasting the variable where it displays my sms message
Toast.makeText(getBaseContext(), addressSms, Toast.LENGTH_LONG).show();
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setUpMapIfNeeded();
mAddress = (TextView) findViewById(R.id.address);
// As the app loads, the address bar will be displayed
mActivityIndicator = (ProgressBar) findViewById(R.id.address_progress);
// Setting the map type to be Hybrid
mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
// Create the LocationRequest object
mLocationRequest = LocationRequest.create();
// Use high accuracy
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
// Set the update interval to 5 seconds
mLocationRequest.setInterval(UPDATE_INTERVAL);
// Set the fastest update interval to 1 second
mLocationRequest.setFastestInterval(FASTEST_INTERVAL);
/*
* Create a new location client, using the enclosing class to handle
* callbacks.
*/
mLocationClient = new LocationClient(this, this, this);
//Creating the new intent
intentFilter = new IntentFilter();
intentFilter.addAction("SMS_RECEIVED_ACTION");
registerReceiver(intentReceiver, intentFilter);
}
private void setUpMapIfNeeded() {
// Do a null check to confirm that we have not already instantiated the
// map.
if (mMap == null) {
mMap = ((MapFragment) getFragmentManager().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.
}
}
}
// When the application is started
@Override
protected void onStart() {
super.onStart();
// Connect the client.
mLocationClient.connect();
}
private class GetAddressTask extends AsyncTask<Location, Void, String> {
Context mContext;
public GetAddressTask(Context context) {
super();
mContext = context;
}
protected String doInBackground(Location... params) {
Geocoder geocoder = new Geocoder(mContext, Locale.getDefault());
// Get the current location from the input parameter list
Location loc = params[0];
// Create a list to contain the result address
List<Address> addresses = null;
try {
/*
* Return 1 address.
*/
addresses = geocoder.getFromLocation(loc.getLatitude(),
loc.getLongitude(), 1);
} catch (IOException e1) {
Log.e("LocationSampleActivity",
"IO Exception in getFromLocation()");
e1.printStackTrace();
return ("IO Exception trying to get address");
} catch (IllegalArgumentException e2) {
// Error message to post in the log
String errorString = "Illegal arguments "
+ Double.toString(loc.getLatitude()) + " , "
+ Double.toString(loc.getLongitude())
+ " passed to address service";
Log.e("LocationSampleActivity", errorString);
e2.printStackTrace();
return errorString;
}
// If the reverse geocode returned an address
if (addresses != null && addresses.size() > 0) {
// Get the first address
Address address = addresses.get(0);
/*
* Format the first line of address (if available), city, and
* country name.
*/
addressText = String.format(
"%s, %s, %s",
// If there's a street address, add it
address.getMaxAddressLineIndex() > 0 ? address
.getAddressLine(0) : "",
// Locality is usually a city
address.getLocality(),
// The country of the address
address.getCountryName());
// Return the text
return addressText;
} else {
return "No address found";
}
}
protected void onPostExecute(String address) {
// Set activity indicator visibility to "gone"
mActivityIndicator.setVisibility(View.GONE);
// Display the results of the lookup.
mAddress.setText(address);
}
}
// When the connection is made to get live updates
public void onConnected(Bundle dataBundle) {
// Display the connection status
Toast.makeText(this, "Connected", Toast.LENGTH_SHORT).show();
// Start periodic updates
mLocationClient.requestLocationUpdates(mLocationRequest, this);
}
// When the new coordinates are put into the DDMS, the map will change to
// that location and get the new address
public void onLocationChanged(Location location) {
// Report to the UI that the location was updated
LatLng latlng = new LatLng(location.getLatitude(),
location.getLongitude());
mMap.moveCamera(CameraUpdateFactory.newLatLng(latlng));
mActivityIndicator.setVisibility(View.VISIBLE);
/*
* Reverse geocoding is long-running and synchronous. Run it on a
* background thread. Pass the current location to the background task.
* When the task finishes, onPostExecute() displays the address.
*/
(new GetAddressTask(this)).execute(location);
}
@Override
public void onConnectionFailed(ConnectionResult arg0) {
}
@Override
public void onDisconnected() {
}
// Click on button to get the read me file to know how to use the
// application
public void readMeClicked(View v) {
// Create a dialog to pop up and explain the application to the user
AlertDialog alertDialog = new AlertDialog.Builder(this).create(); // Read
// Update
alertDialog.setTitle("Read Me");
alertDialog
.setMessage("My app was created to be able to quickly send out an emergency SMS to a certain individual which will contain the emergency message as well as their current location. By using the DDMS, the coordinates can be input and then my app will go to that specific location and pull the most correct address of that location");
// Making the dialog show
alertDialog.show();
}
public void getFromLocationClicked(View v) {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(
MainActivity.this);
// Setting Dialog Title
alertDialog.setTitle("Emergency SMS");
// Setting Dialog Message
alertDialog.setMessage("Enter Emergency Contact Number");
final EditText input = new EditText(MainActivity.this);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.MATCH_PARENT);
input.setLayoutParams(lp);
alertDialog.setView(input);
// Setting Positive "Continue" Button
alertDialog.setPositiveButton("Continue",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
String testing = input.getText().toString();
getFromLocation(testing);
}
});
// Setting Negative "Cancel" Button
alertDialog.setNegativeButton("Cancel",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
};
public void getFromLocation(String strAddress) {
Geocoder coder = new Geocoder(this);
List<Address> address;
try {
address = coder.getFromLocationName(strAddress, 5);
if (address != null) {
Address location = address.get(0);
double recLat = location.getLatitude();
double recLng = location.getLongitude();
LatLng p = new LatLng(recLat, recLng);
Toast.makeText(getBaseContext(), p + "", Toast.LENGTH_LONG)
.show();
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(p, 16));
}
} catch (IOException ie) {
ie.printStackTrace();
}
}
//Showing the value when the show button is clicked
public void showOnMapClicked(View v)
{
//When it toasts, the addressSms value is now null!??
Toast.makeText(getBaseContext(), addressSms, Toast.LENGTH_LONG).show();
//getFromLocation(addressSms);
}
public void showToast(String message)
{
String test = message;
Toast.makeText(getBaseContext(), test, Toast.LENGTH_LONG).show();
}
// Click the button to start to generate the emergency SMS
public void sendAddressClicked(final View v) {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(
MainActivity.this);
// Setting Dialog Title
alertDialog.setTitle("Emergency SMS");
// Setting Dialog Message
alertDialog.setMessage("Enter Emergency Contact Number");
final EditText input = new EditText(MainActivity.this);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.MATCH_PARENT);
input.setLayoutParams(lp);
alertDialog.setView(input);
input.setFilters(new InputFilter[] {
// Maximum 2 characters.
new InputFilter.LengthFilter(10),
// Digits only.
DigitsKeyListener.getInstance(), // Not strictly needed, IMHO.
});
// Setting Positive "Continue" Button
alertDialog.setPositiveButton("Continue",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// Setting the SMS message and adding the current
// location which is gathered by the map.
String textMessage = input.getText().toString();
// Checking if the phone number is not blank
if (textMessage.isEmpty()) {
// If the phone number is not entered
Toast.makeText(getBaseContext(),
"Cannot be blank. Enter phone number.",
Toast.LENGTH_LONG).show();
sendAddressClicked(v);
}
else {
enterMessage(textMessage);
}
}
});
// Setting Negative "Cancel" Button
alertDialog.setNegativeButton("Cancel",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
};
// Method to send the emergency method and the current location
private void sendSMS(String phoneNumber, String message) {
// Sending the sms to the emulator number input
SmsManager sms = SmsManager.getDefault();
sms.sendTextMessage(phoneNumber, null, message, null, null);
}
// Once the user has input the number, the message now will be asked for
public void enterMessage(final String number) {
// Creating the dialog to input the emergency message
AlertDialog.Builder alertDialog = new AlertDialog.Builder(
MainActivity.this);
// Setting Dialog Title
alertDialog.setTitle("Emergency SMS");
// Setting Dialog Message
alertDialog.setMessage("Enter Emergency SMS");
final EditText input = new EditText(MainActivity.this);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.MATCH_PARENT);
input.setLayoutParams(lp);
alertDialog.setView(input);
input.setInputType(InputType.TYPE_CLASS_TEXT);
// Setting Positive "SEND SMS" Button
alertDialog.setPositiveButton("SEND SMS",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// Write your code here to execute after dialog
// Setting the SMS message and adding the current
// location which is gathered by the map.
String textMessage = input.getText().toString();
String SMS = textMessage + "\n\n"
+ "My Current Address Is: " + addressText;
String phoneNumber = number;
// Checking to see if the SMS is blank
if (textMessage.isEmpty()) {
Toast.makeText(getBaseContext(),
"Cannot be blank. Enter emergency SMS.",
Toast.LENGTH_LONG).show();
enterMessage(phoneNumber);
}
else {
// Sending the variables through to the sendSMS
// method to be sent
sendSMS(phoneNumber, SMS);
}
}
});
// Setting Negative "Cancel" Button
alertDialog.setNegativeButton("Cancel",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// Write your code here to execute after dialog
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
};
}