纬度和经度值未显示在 TextView 中
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【中文标题】纬度和经度值未显示在 TextView 中【英文标题】：Latitude and Longitude values not displayng in TextView 【发布时间】：2013-01-11 18:24:03 【问题描述】：我正在编写一个应用程序，用户可以在其中填写活动表单并将其同步到网络服务。应用程序的一部分涉及地理定位，因此，纬度和经度值。我希望我的应用程序自动定位一个人的智能手机的地理位置（它成功地做到了这一点），然后自动填写活动表单上的 TextView。我尝试了一些方法，但无济于事。谁能告诉我我哪里出错了？
这是 DataEntry 类：-
package application.prototype.mfb;
import android.location.Location;
import android.location.LocationManager;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
import application.prototype.mfb.MyLocation.LocationResult;
/**
* Records a new data form entry for a favourite building
* @author DanielD
*
*/
public class DataEntry extends Activity implements OnClickListener
Button btnClear;
Button btnSync;
EditText txtBuildingName;
EditText txtDescription;
TextView txtLongitude;
TextView txtLatitude;
Spinner project;
public static Location loc;
private static double longitude;
private static double latitude;
private static String name;
private static String description;
private static String projectString;
private static String lngString = String.valueOf(longitude);
private static String latString = String.valueOf(latitude);
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_data_entry);
LocationResult locationResult = new LocationResult()
@Override
public void gotLocation(Location location)
loc = location;
latitude = loc.getLatitude();
longitude = loc.getLongitude();
System.out.println("Latitude: " + latitude);
System.out.println("Longitude: " + longitude);
;
MyLocation myLocation = new MyLocation();
myLocation.getLocation(DataEntry.this, locationResult);
txtBuildingName=(EditText)this.findViewById(R.id.nameContent);
txtDescription=(EditText)this.findViewById(R.id.descriptionContent);
project=(Spinner)findViewById(R.id.type_project);
ArrayAdapter<CharSequence> adapterTwo = ArrayAdapter.createFromResource(this, R.array.type_project_array, android.R.layout.simple_spinner_item);
project.setAdapter(adapterTwo);
txtLatitude=(TextView)this.findViewById(R.id.TextViewLat);
txtLongitude=(TextView)this.findViewById(R.id.TextViewLong);
/*These checks will ensure that if a variable still has user data in it, it will refill the fields with that data preventing users entering
* the same information multiple times
*/
if(name != null)
txtBuildingName.setText(name);
if(description != null)
txtDescription.setText(description);
if(projectString != null)
project.getItemAtPosition(project.getSelectedItemPosition()).toString();
if(latString != null)
txtLatitude.setText(latString);
if(lngString != null)
txtLongitude.setText(lngString);
btnClear=(Button)findViewById(R.id.btnClear);
btnClear.setOnClickListener(this);
btnSync=(Button)findViewById(R.id.btnSync);
btnSync.setOnClickListener(new OnClickListener()
public void onClick(View v) //NEW VERSION OF COMMIT DATA - WILL PRESERVE DATA OVER ACTIVITY
if(txtBuildingName.getText().toString().length() > 0)
name = txtBuildingName.getText().toString();
if(txtDescription.getText().toString().length() > 0)
description = txtDescription.getText().toString();
if(project.getItemAtPosition(project.getSelectedItemPosition()).toString().length() > 0)
projectString = project.getItemAtPosition(project.getSelectedItemPosition()).toString();
Intent intent = new Intent(DataEntry.this, DataSummary.class);
startActivity(intent);
);
public static String getName()
return name;
public static String getDescription()
return description;
public static String getLongitude()
return lngString;
public static String getLatitude()
return latString;
/*public Location getLongitude()
LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
longitude = location.getLongitude();
return longitude;
public Location getLatitude()
LocationManager lm = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
Location location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
latitude = location.getLatitude();
latitudeString = String.valueOf(latitude);
return latitudeString;
*/
public static String getProject()
return projectString;
public void onSaveInstanceState(Bundle outState)
super.onSaveInstanceState(outState);
public void onRestoredInstanceState(Bundle returnState)
super.onRestoreInstanceState(returnState);
@Override
public boolean onCreateOptionsMenu(Menu menu)
getMenuInflater().inflate(R.menu.activity_favourite_building, menu);
return true;
public void onClick(View v)
switch(v.getId())
case R.id.btnClear : clearFields();
break;
/**
* Switch statement governing the different options available on the Action Bar
*/
public boolean onOptionsItemSelected(MenuItem item)
switch(item.getItemId())
case R.id.app_camera:
Intent intentZero = new Intent(this, CameraDemo.class);
intentZero.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intentZero);
return true;
case R.id.app_dataentry:
Intent intent = new Intent(this, DataEntry.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
return true;
case R.id.app_syncorsave:
Intent intentOne = new Intent(this, DataSummary.class);
intentOne.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intentOne);
return true;
case R.id.app_discard:
Intent intentTwo = new Intent(this, DeleteProjects.class);
intentTwo.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intentTwo);
return true;
case R.id.app_homescreen:
Intent intentThree = new Intent(this, ProjectGrid.class);
intentThree.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intentThree);
return true;
default:
return super.onOptionsItemSelected(item);
public void clearFields()
Toast.makeText(DataEntry.this, "All fields Reset", Toast.LENGTH_LONG).show();
txtBuildingName.getEditableText().clear();
txtDescription.getEditableText().clear();
name = ""; //must also set the static variables to blank otherwise previous data still assigned in variable.
description = "";
projectString = "";
这里是 MyLocation.java 类：-
package application.prototype.mfb;
import java.util.Timer;
import java.util.TimerTask;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
public class MyLocation
Timer timer1;
LocationManager lm;
LocationResult locationResult;
boolean gps_enabled=false;
boolean network_enabled=false;
public boolean getLocation(Context context, LocationResult result)
//I use LocationResult callback class to pass location value from MyLocation to user code.
locationResult=result;
if(lm==null)
lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
//exceptions will be thrown if provider is not permitted.
try
gps_enabled=lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
catch(Exception ex)
ex.printStackTrace();
try
network_enabled=lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
catch(Exception ex)
ex.printStackTrace();
//don't start listeners if no provider is enabled
if(!gps_enabled && !network_enabled)
return false;
if(gps_enabled)
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps);
if(network_enabled)
lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork);
timer1=new Timer();
timer1.schedule(new GetLastLocation(), 20000);
return true;
LocationListener locationListenerGps = new LocationListener()
public void onLocationChanged(Location location)
timer1.cancel();
locationResult.gotLocation(location);
// lm.removeUpdates(this);
//lm.removeUpdates(locationListenerNetwork);
public void onProviderDisabled(String provider)
public void onProviderEnabled(String provider)
public void onStatusChanged(String provider, int status, Bundle extras)
;
LocationListener locationListenerNetwork = new LocationListener()
public void onLocationChanged(Location location)
timer1.cancel();
locationResult.gotLocation(location);
// lm.removeUpdates(this);
// lm.removeUpdates(locationListenerGps);
public void onProviderDisabled(String provider)
public void onProviderEnabled(String provider)
public void onStatusChanged(String provider, int status, Bundle extras)
;
class GetLastLocation extends TimerTask
@Override
public void run()
//lm.removeUpdates(locationListenerGps);
//lm.removeUpdates(locationListenerNetwork);
Location net_loc=null, gps_loc=null;
if(gps_enabled)
gps_loc=lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(network_enabled)
net_loc=lm.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
//if there are both values use the latest one
if(gps_loc!=null && net_loc!=null)
if(gps_loc.getTime()>net_loc.getTime())
locationResult.gotLocation(gps_loc);
else
locationResult.gotLocation(net_loc);
return;
if(gps_loc!=null)
locationResult.gotLocation(gps_loc);
return;
if(net_loc!=null)
locationResult.gotLocation(net_loc);
return;
locationResult.gotLocation(null);
public static abstract class LocationResult
public abstract void gotLocation(Location location);
现在，我添加了 System.out.println 方法，以在 logcat 日志中识别是否找到了位置值并且它们已经找到（见下文）。那么如何获取这些值并将它们转换为合适的格式以显示在 TextView 中？
01-11 18:04:01.885: I/System.out(541): Latitude: -4.066498333333333
01-11 18:04:01.885: I/System.out(541): Longitude: 52.410999999999994
*从生成的 logcat 文件中提取。
【问题讨论】：
您只需使用坐标设置文本字段 合适的格式是什么意思？？ 【参考方案1】：那么我如何获取这些值并将它们转换为合适的格式以显示在 TextView 中？
显示它们很容易，您已经完成了 98% 的工作，只需添加：
LocationResult locationResult = new LocationResult()
@Override
public void gotLocation(Location location)
loc = location;
latitude = loc.getLatitude();
longitude = loc.getLongitude();
txtLatitude.setText(latitude + "");
txtLongitude.setText(longitude + "");
System.out.println("Latitude: " + latitude);
System.out.println("Longitude: " + longitude);
;
但是“合适的格式”有点模糊……你想要什么格式？您可以使用Location.convert() 来使用更传统的hour:minute:second.fraction 格式。
【讨论】：
抱歉，对合适的格式含糊其辞，我只是指一种符合 TextView 的格式，因此本质上是一个字符串。感谢您的帮助，这是一种享受。正确答案。【参考方案2】：TextView tvLongitude=(TextView)findViewById(R.id.textViewlongitude);
TextView tvLatitude=(TextView)findViewById(R.id.textViewlatitude);
tvLongitude.setText("Longitude is"+longitude );
tvLatitude.setText("Latitude is"+latitude );
这样你就可以在textview上设置值了
【讨论】：
【参考方案3】：嗯，快速查看您的代码，您正在 System.out 中打印您在 Result 回调中收到的双精度值，但您永远不会填充您试图放在 TextViews 上的两个字符串变量。
你应该在 Location 回调中重新填充你的变量
LocationResult locationResult = new LocationResult()
@Override
public void gotLocation(Location location)
loc = location;
latitude = loc.getLatitude();
longitude = loc.getLongitude();
lngString = String.valueOf(longitude);
latString = String.valueOf(latitude);
System.out.println("Latitude: " + latitude);
System.out.println("Longitude: " + longitude);
;
【讨论】：
【参考方案4】：在 textview 上显示
你的布局activity_data_entry.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/LinearLayout1"
android:layout_
android:layout_
android:orientation="vertical" >
<TextView
android:id="@+id/textViewlatitude"
android:layout_
android:layout_ />
<TextView
android:id="@+id/textViewlongitude"
android:layout_
android:layout_/>
</LinearLayout>
内部代码：
LocationResult locationResult = new LocationResult()
@Override
public void gotLocation(Location location)
loc = location;
latitude = loc.getLatitude();
longitude = loc.getLongitude();
TextView tvLongitude=(TextView)findViewById(R.id.textViewlongitude);
TextView tvLatitude=(TextView)findViewById(R.id.textViewlatitude);
tvLongitude.setText("Longitude is"+longitude );
tvLatitude.setText("Latitude is"+latitude );
;
但是你说的合适的格式是什么意思？？
【讨论】：
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