Как обновить TextView с GPS-координатами

Question

Я НОВИНКА для разработки Android и Java, поэтому, пожалуйста, будьте терпеливы со мной :) Я пытаюсь получить GPS-координаты своего телефона, а затем обновлять TextView с широтой (мне просто нужна широта на данный момент). Вот то, что я до сих пор:

main.xml: 

[...] 
    <Button 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:text="Get my location" 
     android:id="@+id/button2" 
     android:layout_gravity="center_horizontal" 
     android:onClick="returnMyCoordinates" /> 

<TextView 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textAppearance="?android:attr/textAppearanceMedium" 
    android:text="This is where the lat value will show up" 
    android:id="@+id/latitudeResult" /> 

MapsActivity.java: 

     public void returnMyCoordinates(View v, Location location){ 
     double latiTude; 
     latiTude = location.getLatitude(); 
     String lat_value; 
     lat_value = Double.toString(latiTude); 
     TextView latView = (TextView) findViewById(R.id.latitudeResult); 
     latView.setText(lat_value); 
    } 

Это мое понимание того, что я не могу объединить «View V» с другими параметрами в объявлении метода. Если это так, то почему? И как еще я мог это сделать?

Вот весь файл для контекста:

package com.example.googlemapsandroidapi; 

import android.content.Context; 
import android.content.pm.PackageManager; 
import android.location.Location; 
import android.location.LocationListener; 
import android.location.LocationManager; 
import android.os.Bundle; 
import android.support.annotation.NonNull; 
import android.support.v4.app.ActivityCompat; 
import android.support.v4.app.FragmentActivity; 
import android.util.Log; 
import android.view.View; 
import android.widget.TextView; 
import android.widget.Toast; 

import com.google.android.gms.maps.CameraUpdateFactory; 
import com.google.android.gms.maps.GoogleMap; 
import com.google.android.gms.maps.OnMapReadyCallback; 
import com.google.android.gms.maps.SupportMapFragment; 
import com.google.android.gms.maps.model.BitmapDescriptorFactory; 
import com.google.android.gms.maps.model.LatLng; 
import com.google.android.gms.maps.model.Marker; 
import com.google.android.gms.maps.model.MarkerOptions; 

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback,LocationListener{ 

    private GoogleMap mMap = null; 
    protected LocationManager locationManager; 
    Double lat; 
    Double long1; 
    TextView txtLat; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 

    } 

     public void returnMyCoordinates(View v, Location location){ 
     double latiTude; 
     latiTude = location.getLatitude(); 
     String lat_value; 
     lat_value = Double.toString(latiTude); 
     TextView latView = (TextView) findViewById(R.id.latitudeResult); 
     latView.setText(lat_value); 
    } 


    public void showLocation(View v) { 
    setContentView(R.layout.activity_maps); 
    SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager() 
    .findFragmentById(R.id.map); 
    mapFragment.getMapAsync(MapsActivity.this); 

    ActivityCompat.requestPermissions(MapsActivity.this, 
    new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION}, 
    1); 

    locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); 
    try { 
    locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 250000, 0, this); 
    locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 250000, 0, this); 
    if(mMap!=null){ 
    mMap.setMyLocationEnabled(true); 
    } 
    Log.e("TAG","Location Manager Called Successfully."); 
    }catch (SecurityException e){ 
    e.printStackTrace(); 
    Log.e("TAG","SecurityException:"+e.getMessage()); 
    } 
    } 


    @Override 
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { 
     switch (requestCode) { 
      case 1: 
       if (grantResults.length > 0 
         && grantResults[0] == PackageManager.PERMISSION_GRANTED) { 
        try { 
         locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 250000, 0, MapsActivity.this); 
         locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 250000, 0, MapsActivity.this); 
         if(mMap!=null){ 
          mMap.setMyLocationEnabled(true); 
         } 
         Log.e("TAG","Location Manager Called Successfully."); 
        }catch (SecurityException e){ 
         e.printStackTrace(); 
         Log.e("TAG","SecurityException:"+e.getMessage()); 
        } 
       } else { 
        Toast.makeText(MapsActivity.this,"Sorry We Need All Permissions Open App Again and Allow All.",Toast.LENGTH_LONG).show(); 
        MapsActivity.this.finish(); 
       } 
       return; 
     } 
    } 


    @Override 
    public void onMapReady(GoogleMap googleMap) { 
     mMap = googleMap; 

     // Add a marker in Sydney and move the camera 
     /*LatLng sydney = new LatLng(-34, 151); 
     mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney")); 
     mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));*/ 
    } 


    @Override 
    public void onStatusChanged(String s, int i, Bundle bundle) { 

    } 

    @Override 
    public void onProviderEnabled(String s) { 

    } 

    @Override 
    public void onProviderDisabled(String s) { 

    } 
} 

Answer 1

Попробуйте инициализацию TextView latView = (TextView) findViewById(R.id.latitudeResult); в методе onCreate, так как я думаю, что ваш MapsActivity.java является активностью можете ли вы опубликовать весь MapActivity.java в любом случае.

Answer 2

Просьба попробовать, используя все классы. MainActivity.class:

public class MainActivity extends Activity implements 
    ConnectionCallbacks, OnConnectionFailedListener, View.OnClickListener { 


protected GoogleApiClient mGoogleApiClient; 
protected Location location; 
protected boolean mAddressRequested; 
protected String mAddressOutput; 
private AddressResultReceiver mResultReceiver; 
ProgressBar mProgressBar; 
private Button btnCurrentLocation, btnShowAddress; 
private TextView tvSetLat, tvSetLang, tvAddress; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    setId(); 
    setListener(); 

    mProgressBar = (ProgressBar) findViewById(R.id.progress_bar); 


    updateValuesFromBundle(savedInstanceState); 
    buildGoogleApiClient(); 
} 


private void setId() { 
    tvSetLat = (TextView) findViewById(R.id.tvSetLat); 
    tvSetLang = (TextView) findViewById(R.id.tvSetLang); 
    btnCurrentLocation = (Button) findViewById(R.id.btnCurrentLocation); 


} 


private void setListener() { 
    btnCurrentLocation.setOnClickListener(this); 


} 

private void updateValuesFromBundle(Bundle savedInstanceState) { 

} 

protected synchronized void buildGoogleApiClient() { 
    mGoogleApiClient = new GoogleApiClient.Builder(this) 
      .addConnectionCallbacks(this) 
      .addOnConnectionFailedListener(this) 
      .addApi(LocationServices.API) 
      .build(); 
} 


@Override 
protected void onStart() { 
    super.onStart(); 
    mGoogleApiClient.connect(); 
} 

@Override 
protected void onStop() { 
    super.onStop(); 
    if (mGoogleApiClient.isConnected()) { 
     mGoogleApiClient.disconnect(); 
    } 
} 

@Override 
public void onConnected(Bundle connectionHint) { 
    if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { 
     return; 
    } 
    location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient); 
    if (location != null) { 
     if (!Geocoder.isPresent()) { 
      Toast.makeText(this, R.string.no_geocoder_available, Toast.LENGTH_LONG).show(); 
      return; 
     } 
     if (mAddressRequested) { 
      startIntentService(); 
     } 
    } 
} 


@Override 
public void onConnectionFailed(ConnectionResult result) { 
    Log.i(TAG, "Connection failed: ConnectionResult.getErrorCode() = " + result.getErrorCode()); 
} 


@Override 
public void onConnectionSuspended(int cause) { 
    Log.i(TAG, "Connection suspended"); 
    mGoogleApiClient.connect(); 
} 


protected void showToast(String text) { 
    Toast.makeText(this, text, Toast.LENGTH_SHORT).show(); 
} 

@Override 
public void onSaveInstanceState(Bundle savedInstanceState) { 
    savedInstanceState.putBoolean(ADDRESS_REQUESTED_KEY, mAddressRequested); 
    savedInstanceState.putString(LOCATION_ADDRESS_KEY, mAddressOutput); 
    super.onSaveInstanceState(savedInstanceState); 
} 


@Override 
public void onClick(View view) { 

    switch (view.getId()) { 
     case R.id.btnCurrentLocation: 
      if (location != null) { 
       tvSetLat.setText(String.valueOf(location.getLatitude())); 
       tvSetLang.setText(String.valueOf(location.getLongitude())); 
      } 
      break; 


     default: 
      break; 
    } 
} 

}

ваш XML является activity_main

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:tools="http://schemas.android.com/tools" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:orientation="vertical" 
tools:context="com.example.android.geocoderdemo.MainActivity"> 

<ProgressBar 
    android:id="@+id/progress_bar" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_centerInParent="true" /> 

<LinearLayout 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:weightSum="1"> 

    <TextView 
     android:id="@+id/tvSetLat" 
     android:layout_width="0dp" 
     android:layout_height="wrap_content" 
     android:layout_weight=".50" 
     android:padding="10dp" 
     android:text="set lat" /> 

    <TextView 
     android:id="@+id/tvSetLang" 
     android:layout_width="0dp" 
     android:layout_height="wrap_content" 
     android:layout_weight=".50" 
     android:padding="10dp" 
     android:text="set long" /> 

</LinearLayout> 

<LinearLayout 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:weightSum="1"> 


    <Button 
     android:id="@+id/btnCurrentLocation" 
     android:layout_width="0dp" 
     android:layout_height="wrap_content" 
     android:layout_weight=".50" 
     android:gravity="center" 
     android:text="Get Current Location" /> 

</LinearLayout> 

и добавить разрешение в menifest:

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> 

A Также добавьте playervice в gradle.

compile 'com.google.android.gms:play-services:9.4.0' 

Вы можете увидеть мое приложение gradle.

apply plugin: 'com.android.application' 

андроид { compileSdkVersion 24 buildToolsVersion "24.0.1"

defaultConfig { 
    applicationId "com.example.android.geocoderdemo" 
    minSdkVersion 15 
    targetSdkVersion 24 
    versionCode 1 
    versionName "1.0" 
    multiDexEnabled true 
} 
buildTypes { 
    release { 
     minifyEnabled false 
     proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro' 
    } 
} 

}

зависимостей { компиляции (в том числе дереве файлов: [ '* .jar'], реж: ' libs ') testCompile' junit: junit: 4.12 ' compile' com.android.support:multidex:1.0.0 ' compile' com.android.support:appcompat-v7:24.1.1 ' компиляции 'com.google.android.gms: играть-услуги: 9.4.0' }