我正在制作天气应用程序，目前的问题是天气正在根据位置的默认值进行更新，而不是等待方法getLocation()更新位置。一旦我刷新，一切正常，但这不是我喜欢在我的应用程序中发生的事情。这是我的MainActivity.java：请原谅这个烂摊子。它是在代码片段之后从代码片段编译的，需要重新组织。
package com.nrsmac.stormy.ui;
import android.content.Context;
import android.content.Intent;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.Toast;
import com.nrsmac.stormy.R;
import com.nrsmac.stormy.weather.Current;
import com.nrsmac.stormy.weather.Day;
import com.nrsmac.stormy.weather.Forecast;
import com.nrsmac.stormy.weather.Hour;
import com.squareup.okhttp.Call;
import com.squareup.okhttp.Callback;
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.Response;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.IOException;
import java.util.List;
import java.util.Locale;
import butterknife.ButterKnife;
import butterknife.InjectView;
import butterknife.OnClick;
public class MainActivity extends ActionBarActivity {
public static final String TAG = MainActivity.class.getSimpleName();
public static final String DAILY_FORECAST = "DAILY_FORECAST";
public static final String HOURLY_FORECAST = "HOURLY_FORECAST";
//9.927128 -84.082012 San José, Costa Rica
private double mLatitude = 0;
private double mLongitude = 0;
public static String cityName = null;
public static int backgroundColor;
private Forecast mForecast;
@InjectView(R.id.relativeLayout)
RelativeLayout mRelativeLayout;
@InjectView(R.id.timeLabel)
TextView mTimeLabel;
@InjectView(R.id.temperatureLabel)
TextView mTemperatureLabel;
@InjectView(R.id.humidityValue)
TextView mHumidityValue;
@InjectView(R.id.precipValue)
TextView mPrecipValue;
@InjectView(R.id.summaryLabel)
TextView mSummaryLabel;
//@InjectView(R.id.iconImageView) ImageView mIconImageView;
@InjectView(R.id.refreshImageView)
ImageView mRefreshImageView;
@InjectView(R.id.progressBar)
ProgressBar mProgressBar;
@InjectView(R.id.locationLabel)
TextView mLocationLabel;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.inject(this);
mProgressBar.setVisibility(View.INVISIBLE);
getLocation();
mRefreshImageView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
getForecast(mLatitude, mLongitude);
}
});
getForecast(mLatitude, mLongitude);
Log.d(TAG, "Main UI code is running!");
}
public void getLocation() {
LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
LocationListener ll = new LocationListener() {
@Override
public void onLocationChanged(Location location) {
if (location != null){
double pLong = location.getLongitude();
double pLat = location.getLatitude();
mLongitude = pLong;
mLatitude = pLat;
}
String longitude = "Longitude: " + location.getLongitude();
Log.v(TAG, longitude);
String latitude = "Latitude: " + location.getLatitude();
Log.v(TAG, latitude);
/*----------to get City-Name from coordinates ------------- */
Geocoder gcd = new Geocoder(getBaseContext(), Locale.getDefault());
List<Address> addresses;
try {
addresses = gcd.getFromLocation(location.getLatitude(),
location.getLongitude(), 1);
if (addresses.size() > 0)
System.out.println(addresses.get(0).getLocality());
cityName = addresses.get(0).getLocality();
} catch (IOException e) {
e.printStackTrace();
}
mLocationLabel.setText(cityName);
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
};
//took this to line 123 out to test for gps always on bug, using only line 124 right now
//exceptions will be thrown if provider is not permitted.
// try{gps_enabled=lm.isProviderEnabled(LocationManager.GPS_PROVIDER);}catch(Exception ex){}
//try{network_enabled=lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);}catch(Exception ex){}
// if(gps_enabled) {
// lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 100, 100, ll);
//if(network_enabled)
// lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 100, 100, ll);
// }
lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 100, 100, ll);
// if update broke it, try un-commenting this line, comment out above line?
//lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 10, 10, ll);
}
private void getForecast(double latitude, double longitude) {
String apiKey = "7a73984cc278e10ed332f1e5d6db96e9";
String forecastUrl = "https://api.forecast.io/forecast/" + apiKey + "/" + latitude + "," + longitude;
if (isNetworkAvailable()) {
toggleRefresh();
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url(forecastUrl)
.build();
Call call = client.newCall(request);
call.enqueue(new Callback() {
@Override
public void onFailure(Request request, IOException e) {
runOnUiThread(new Runnable() {
@Override
public void run() {
toggleRefresh();
}
});
alertUserAboutError();
}
@Override
public void onResponse(Response response) throws IOException {
runOnUiThread(new Runnable() {
@Override
public void run() {
toggleRefresh();
}
});
try {
String jsonData = response.body().string();
Log.v(TAG, jsonData);
if (response.isSuccessful()) {
mForecast = parseForecastDetails(jsonData);
runOnUiThread(new Runnable() {
@Override
public void run() {
updateDisplay();
}
});
} else {
alertUserAboutError();
}
} catch (IOException e) {
Log.e(TAG, "Exception caught", e);
} catch (JSONException e) {
Log.e(TAG, "Exception caught", e);
}
}
});
} else {
Toast.makeText(this, getString(R.string.network_unavailible_message),
Toast.LENGTH_LONG).show();
}
}
private void toggleRefresh() {
getLocation();
if (mProgressBar.getVisibility() == View.INVISIBLE) {
mProgressBar.setVisibility(View.VISIBLE);
mRefreshImageView.setVisibility(View.INVISIBLE);
}
else {
mProgressBar.setVisibility(View.INVISIBLE);
mRefreshImageView.setVisibility(View.VISIBLE);
}
}
private void updateDisplay() {
getLocation();
Current current = mForecast.getCurrent();
mTemperatureLabel.setText(current.getTemperature() + " degrees");
mTimeLabel.setText(current.getFormattedTime());
mHumidityValue.setText(current.getHumidity() + "");
mPrecipValue.setText(current.getPrecipChance() + "%");
mSummaryLabel.setText(current.getSummary());
// Drawable drawable = getResources().getDrawable(current.getIconId());
// mIconImageView.setImageDrawable(drawable);
backgroundColor = current.getBackgroundColor();
mRelativeLayout.setBackgroundColor(backgroundColor);
}
private Forecast parseForecastDetails(String jsonData) throws JSONException {
Forecast forecast = new Forecast();
forecast.setCurrent(getCurrentDetails(jsonData));
forecast.setHourlyForecast(getHourlyForecast(jsonData));
forecast.setDailyForecast(getDailyForecast(jsonData));
return forecast;
}
private Day[] getDailyForecast(String jsonData) throws JSONException {
JSONObject forecast = new JSONObject(jsonData);
String timezone = forecast.getString("timezone");
JSONObject daily = forecast.getJSONObject("daily");
JSONArray data = daily.getJSONArray("data");
Day[] days = new Day[data.length()];
for (int i = 0; i < data.length(); i++) {
JSONObject jsonDay = data.getJSONObject(i);
Day day = new Day();
day.setSummary(jsonDay.getString("summary"));
day.setIcon(jsonDay.getString("icon"));
day.setTemperatureMax(jsonDay.getDouble("temperatureMax"));
day.setTime(jsonDay.getLong("time"));
day.setTimezone(timezone);
days[i] = day;
}
return days;
}
private Hour[] getHourlyForecast(String jsonData) throws JSONException{
JSONObject forecast = new JSONObject(jsonData);
String timezone = forecast.getString("timezone");
JSONObject hourly = forecast.getJSONObject("hourly");
JSONArray data = hourly.getJSONArray("data");
Hour[] hours = new Hour[data.length()];
for (int i = 0; i < data.length(); i++) {
JSONObject jsonHour = data.getJSONObject(i);
Hour hour = new Hour();
hour.setSummary(jsonHour.getString("summary"));
hour.setTemperature(jsonHour.getDouble("temperature"));
hour.setIcon(jsonHour.getString("icon"));
hour.setTime(jsonHour.getLong("time"));
hour.setTimezone(timezone);
hours[i] = hour;
}
return hours;
}
private Current getCurrentDetails(String jsonData) throws JSONException {
JSONObject forecast = new JSONObject(jsonData);
String timezone = forecast.getString("timezone");
Log.i(TAG, "From JSON: " + timezone);
JSONObject currently = forecast.getJSONObject("currently");
Current current = new Current();
current.setHumidity(currently.getDouble("humidity"));
current.setTime(currently.getLong("time"));
current.setIcon(currently.getString("icon"));
current.setPrecipChance(currently.getDouble("precipProbability"));
current.setSummary(currently.getString("summary"));
current.setTemperature(currently.getDouble("temperature"));
current.setTimeZone(timezone);
Log.d(TAG, current.getFormattedTime());
return current;
}
private boolean isNetworkAvailable() {
ConnectivityManager manager = (ConnectivityManager)
getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = manager.getActiveNetworkInfo();
boolean isAvailible = false;
if (networkInfo != null && networkInfo.isConnected()) {
isAvailible = true;
}
return isAvailible;
}
private void alertUserAboutError() {
AlertDialogFragment dialog = new AlertDialogFragment();
dialog.show(getFragmentManager(), "error_dialog");
}
@OnClick (R.id.dailyButton)
public void startDailyActivity(View view) {
Intent intent = new Intent(this, DailyForecastActivity.class);
intent.putExtra(DAILY_FORECAST, mForecast.getDailyForecast());
startActivity(intent);
}
@OnClick (R.id.hourlyButton)
public void startHourlyActivity(View view) {
Intent intent = new Intent(this, HourlyForecastActivity.class);
intent.putExtra(HOURLY_FORECAST, mForecast.getHourlyForecast());
startActivity(intent);
}
}
答案 0 :(得分：2)
我和你的一样，我们在同一条船上:)
删除getForecast()中的onCreate。您需要使用google new FusedLocationApi更新当前位置，
因为这可以避免getLastKnowLocation崩溃。如何使用此功能请参阅here，并获取代码here。
然后，您需要handleNewLocation方法onLocationChanged（更新天气）。
和示例代码：
@Override
public void onLocationChanged(Location location) {
handleNewLocation(location);
}
private void handleNewLocation(Location location) {
Log.d(TAG, location.toString());
mLatitude = location.getLatitude();
mLongitude = location.getLongitude();
getForecast(mLatitude, mLongitude);
getCityName();
}
请记住，在更新天气信息之前，请务必先检查mLongitude != 0 && mLatitude != 0。
如果您仍然无法弄清楚，请参阅我的Github here。
答案 1 :(得分：0)
在onCreate中删除对getForecast的调用。这将使它不会立即根据错误的位置获得预测。只有在调用onLocationUpdates后调用getForecast，才能找到正确的位置。