我有一个使用服务的应用。但由于某种原因，该服务无法识别变量“placeArrayList”，“latitudeArrayList”，“longitudeArrayList”和“destination”。
我能在这做什么？
MainActivity.java
public class MainActivity extends AppCompatActivity {
PlacePicker.IntentBuilder builder;
int PLACE_PICKER_REQUEST;
ListView placeListView;
ArrayList<String> placeArrayList;
ArrayList<String> latitudeArrayList;
ArrayList<String> longitudeArrayList;
ArrayAdapter<String> arrayAdapter;
SharedPreferences sharedPreferences;
SharedPreferences.Editor editor;
ArrayList<Double> latitudeList;
Integer counter;
LocationManager locationManager;
String provider;
double lat;
double lng;
Place place;
static Set<String> set;
static Set<String> set1;
static Set<String> set2;
Location location;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
placeListView = (ListView) findViewById(R.id.placeListView);
latitudeList = new ArrayList<>();
placeArrayList = new ArrayList<String>();
latitudeArrayList = new ArrayList<String>();
longitudeArrayList = new ArrayList<String>();
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
String provider = locationManager.getBestProvider(new Criteria(), false);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
final Location location = locationManager.getLastKnownLocation(provider);
final Location destination = new Location(provider);
destination.setLatitude(location.getLatitude());
destination.setLongitude(location.getLongitude());
Log.e("shit", String.valueOf(location.distanceTo(destination)));
ListView listView = (ListView) findViewById(R.id.placeListView);
SharedPreferences sharedPreferences = this.getSharedPreferences("bro", Context.MODE_PRIVATE);
set = sharedPreferences.getStringSet("names", null);
set1 = sharedPreferences.getStringSet("lats", null);
set2 = sharedPreferences.getStringSet("lngs", null);
placeArrayList.clear();
latitudeArrayList.clear();
longitudeArrayList.clear();
if (set != null) {
placeArrayList.addAll(set);
latitudeArrayList.addAll(set1);
longitudeArrayList.addAll(set2);
} else {
placeArrayList.add("Hold to delete");
set = new HashSet<String>();
set.addAll(placeArrayList);
sharedPreferences.edit().putStringSet("names", set).apply();
latitudeArrayList.add(String.valueOf("66.56083"));
set1 = new HashSet<String>();
set1.addAll(latitudeArrayList);
sharedPreferences.edit().putStringSet("lats", set1).apply();
longitudeArrayList.add(String.valueOf("39.3232"));
set2 = new HashSet<String>();
set2.addAll(longitudeArrayList);
sharedPreferences.edit().putStringSet("lngs", set2).apply();
}
arrayAdapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1, placeArrayList);
listView.setAdapter(arrayAdapter);
placeListView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> parent, View view, final int position, long id) {
new AlertDialog.Builder(MainActivity.this)
.setIcon(android.R.drawable.ic_dialog_alert)
.setTitle("Are you sure?")
.setMessage("Do you want to delete this place?")
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
placeArrayList.remove(position);
latitudeArrayList.remove(position);
SharedPreferences sharedPreferences = MainActivity.this.getSharedPreferences("bro", Context.MODE_PRIVATE);
if (set == null) {
set = new HashSet<String>();
set1 = new HashSet<String>();
set2 = new HashSet<String>();
} else {
set.clear();
set1.clear();
set2.clear();
}
set.addAll(placeArrayList);
set1.addAll(latitudeArrayList);
set2.addAll(longitudeArrayList);
sharedPreferences.edit().remove("names").apply();
sharedPreferences.edit().remove("lats").apply();
sharedPreferences.edit().remove("lngs").apply();
sharedPreferences.edit().putStringSet("names", set).apply();
sharedPreferences.edit().putStringSet("lats", set1).apply();
sharedPreferences.edit().putStringSet("lngs", set2).apply();
arrayAdapter.notifyDataSetChanged();
}
})
.setNegativeButton("No", null)
.show();
return false;
}
});
final android.os.Handler handler = new android.os.Handler();
Runnable run = new Runnable() {
@Override
public void run() {
if (location != null) {
lat = location.getLatitude();
lng = location.getLongitude();
if (placeArrayList.size() != 0) {
for (int i = 0; i < placeArrayList.size(); i++) {
Log.e("hello", String.valueOf(Float.parseFloat(latitudeArrayList.get(i))));
destination.setLatitude(Double.parseDouble(latitudeArrayList.get(i)));
destination.setLongitude(Double.parseDouble(longitudeArrayList.get(i)));
Log.e("distancemeters", String.valueOf(location.distanceTo(destination)));
if (location.distanceTo(destination)<100) {
AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
audioManager.setStreamVolume(AudioManager.STREAM_RING, AudioManager.RINGER_MODE_SILENT, AudioManager.FLAG_SHOW_UI);
} else {
}
}
}
}
handler.postDelayed(this, 10000);
}
};
handler.post(run);
arrayAdapter.notifyDataSetChanged();
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
PLACE_PICKER_REQUEST = 1;
builder = new PlacePicker.IntentBuilder();
pickPlace();
}
});
}
public void pickPlace() {
try {
startActivityForResult(builder.build(this), PLACE_PICKER_REQUEST);
} catch (GooglePlayServicesRepairableException e) {
e.printStackTrace();
} catch (GooglePlayServicesNotAvailableException e) {
e.printStackTrace();
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == PLACE_PICKER_REQUEST) {
if (resultCode == RESULT_OK) {
place = PlacePicker.getPlace(data, this);
// String toastMsg = String.format("Place: %s", place.getName());
//Toast.makeText(this, toastMsg, Toast.LENGTH_LONG).show();
placeArrayList.add(String.valueOf(place.getName()));
latitudeArrayList.add(String.valueOf(place.getLatLng().latitude));
longitudeArrayList.add(String.valueOf(place.getLatLng().longitude));
arrayAdapter.notifyDataSetChanged();
startService(new Intent(getBaseContext(), myService.class));
SharedPreferences sharedPreferences = getSharedPreferences("bro", Context.MODE_PRIVATE);
if (set == null) {
set = new HashSet<String>();
set1 = new HashSet<String>();
set2 = new HashSet<String>();
} else {
set.clear();
set1.clear();
set2.clear();
}
arrayAdapter.notifyDataSetChanged();
set.addAll(placeArrayList);
set1.addAll(latitudeArrayList);
set2.addAll(longitudeArrayList);
sharedPreferences.edit().remove("names").apply();
sharedPreferences.edit().remove("lats").apply();
sharedPreferences.edit().remove("lngs").apply();
sharedPreferences.edit().putStringSet("names", set).apply();
sharedPreferences.edit().putStringSet("lats", set1).apply();
sharedPreferences.edit().putStringSet("lngs", set2).apply();
}
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
myService.java
public class myService extends Service implements LocationListener {
Double lat;
Double lng;
@Override
public IBinder onBind(Intent arg0) {
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// Let it continue running until it is stopped.
Toast.makeText(this, "Service Started", Toast.LENGTH_LONG).show();
return START_STICKY;
}
@Override
public void onDestroy() {
super.onDestroy();
Toast.makeText(this, "Service Destroyed", Toast.LENGTH_LONG).show();
}
@Override
public void onLocationChanged(Location location) {
if (location != null) {
lat = location.getLatitude();
lng = location.getLongitude();
if (placeArrayList.size() != 0) {
for (int i = 0; i < placeArrayList.size(); i++) {
Log.e("hello", String.valueOf(Float.parseFloat(latitudeArrayList.get(i))));
destination.setLatitude(Double.parseDouble(latitudeArrayList.get(i)));
destination.setLongitude(Double.parseDouble(longitudeArrayList.get(i)));
Log.e("distancemeters", String.valueOf(location.distanceTo(destination)));
if (location.distanceTo(destination)<100) {
AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
audioManager.setStreamVolume(AudioManager.STREAM_RING, AudioManager.RINGER_MODE_SILENT, AudioManager.FLAG_SHOW_UI);
} else {
}
}
}
}
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
}
答案 0 :(得分：1)
不要将变量设为静态。因为它可能导致内存泄漏。这根本不是一个好主意。 更好的方法是编写一个接口并在MainActivity类中实现它。 此接口将具有为变量分配新值的方法。 并从您的服务中调用Interface方法。
答案 1 :(得分：0)
由于Service是一个单独的类，因此它无法访问MainAcitivity的字段，因为它们超出了“myService”的范围。
如果要在调用Activity和被调用的服务之间共享信息，您将能够通过intent传递键值存储中的数据。
您可以将键值直接放入Intent：
CGAL::Qt::GraphicsViewNavigation* navFilter = new CGAL::Qt::GraphicsViewNavigation(view);
view->viewport()->installEventFilter(navFilter);
您可以构建一个Bundle并将其添加到intent中。 Bundle有一些方法可以更容易地将丰富的数据放入其中。
Intent intent = new Intent(getBaseContext(), myService.class);
itent.putExtra(key, value);
通过文档查看有关Bundle的更多信息：http://developer.android.com/reference/android/os/Bundle.html
如果您对传递大量无法在键值对中轻松表示的数据感兴趣，那么您可能希望将数据组织到您自己的Parceable类中，该类也可以通过Intent传递。查看有关通过文档制作自己的Parceable的更多信息：http://developer.android.com/reference/android/os/Parcelable.html 并通过这个答案 How to send an object from one Android Activity to another using Intents?
答案 2 :(得分：0)
您可以将变量设为静态 然后通过在Activity名称前加上它们来引用它们。