我正在开发使用Map V2 API的android应用程序。我已经编写了所有代码，其中包括权限检查代码和一个Toast当前位置的按钮。
我的问题：第一次运行，当我在手机中安装应用程序时，正在加载的活动会加载地图，但不会显示任何地图控件，例如放大，缩小和缩放到当前位置。但是，当我从正在运行的应用程序中关闭该应用程序并重新打开时，它可以很好地加载所有MAP OPTIONS。 ：（
即使是第一次运行，我也希望加载所有地图选项。当我第一次安装该应用程序时。
这是我的活动代码
import android.Manifest;
import android.app.Activity;
import android.content.Intent;
import android.content.IntentSender;
import android.content.pm.PackageManager;
import android.location.Location;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import com.example.talarir.mapproject.R;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.PendingResult;
import com.google.android.gms.common.api.Status;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.location.LocationSettingsRequest;
import com.google.android.gms.location.LocationSettingsResult;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.location.LocationSettingsStatusCodes;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.OnMapReadyCallback;
import static android.R.attr.permission;
public class MapActivty extends AppCompatActivity implements
OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener,
ResultCallback<LocationSettingsResult> {
protected static final int REQUEST_CHECK_SETTINGS = 0x1;
public static final long UPDATE_INTERVAL_IN_MILLISECONDS = 10000;
public static final long FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS =
UPDATE_INTERVAL_IN_MILLISECONDS / 2;
protected final static String KEY_LOCATION = "location";
protected GoogleApiClient mGoogleApiClient;
protected LocationRequest mLocationRequest;
protected LocationSettingsRequest mLocationSettingsRequest;
public GoogleMap map;
protected Location mCurrentLocation;
Button saveTheLocationBtnNonAdmin;
PendingResult<LocationSettingsResult> result;
static final Integer GPS_SETTINGS = 0x7;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_map_activty);
initializeView();
updateValuesFromBundle(savedInstanceState);
buildGoogleApiClient();
setUpMap();
createLocationRequest();
buildLocationSettingsRequest();
}
private void setUpMap() {
((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMapAsync(this);
}
protected void buildLocationSettingsRequest() {
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder();
builder.addLocationRequest(mLocationRequest);
mLocationSettingsRequest = builder.build();
}
protected void checkLocationSettings() {
PendingResult<LocationSettingsResult> result =
LocationServices.SettingsApi.checkLocationSettings(
mGoogleApiClient,
mLocationSettingsRequest
);
result.setResultCallback(this);
}
protected void createLocationRequest() {
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);
mLocationRequest.setFastestInterval(FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
}
protected synchronized void buildGoogleApiClient() {
Log.i("Map Activity", "Building GoogleApiClient");
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
private void updateValuesFromBundle(Bundle savedInstanceState) {
if (savedInstanceState != null) {
if (savedInstanceState.keySet().contains(KEY_LOCATION)) {
// Since KEY_LOCATION was found in the Bundle, we can be sure that mCurrentLocation
// is not null.
mCurrentLocation = savedInstanceState.getParcelable(KEY_LOCATION);
}
//updateUI();
}
}
private void updateUI() {
if (mCurrentLocation != null) {
Toast.makeText(this,"lat : " + mCurrentLocation.getLatitude() + " \t long : " + mCurrentLocation.getLongitude(),Toast.LENGTH_SHORT).show();
}
}
protected void startLocationUpdates() {
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.
if (ActivityCompat.shouldShowRequestPermissionRationale(MapActivty.this, Manifest.permission.ACCESS_FINE_LOCATION)) {
//This is called if user has denied the permission before
//In this case I am just asking the permission again
ActivityCompat.requestPermissions(MapActivty.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 1);
} else {
ActivityCompat.requestPermissions(MapActivty.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 1);
}
return;
} else {
Toast.makeText(this, "" + permission + " is already granted.", Toast.LENGTH_SHORT).show();
}
LocationServices.FusedLocationApi.requestLocationUpdates(
mGoogleApiClient,
mLocationRequest,
this
).setResultCallback(new ResultCallback<Status>() {
@Override
public void onResult(Status status) {
}
});
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults)
{
switch (requestCode) {
case 1:
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED)
{
// Permission Granted
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED)
{
//mLastLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
askForGPS();
}
startLocationUpdates();
}
else
{
// Permission Denied
Toast.makeText(this, "Permission denied", Toast.LENGTH_SHORT).show();
}
break;
default:
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
private void askForGPS() {
mLocationRequest = LocationRequest.create();
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder().addLocationRequest(mLocationRequest);
builder.setAlwaysShow(true);
result = LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient, builder.build());
result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
@Override
public void onResult(LocationSettingsResult result) {
final Status status = result.getStatus();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
try {
status.startResolutionForResult(MapActivty.this, GPS_SETTINGS);
} catch (IntentSender.SendIntentException e) {
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
break;
}
}
});
}
private void initializeView() {
saveTheLocationBtnNonAdmin = (Button) findViewById(R.id.buttonSaveLocationNonAdmin);
}
public void onClickTheSaveLocationButton(View view) {
//Toast.makeText(this, "hmm : " + mCurrentLocation.getLongitude() + " " + mCurrentLocation.getLatitude(), Toast.LENGTH_SHORT).show();
updateUI();
//stopLocationUpdates();
}
/**
* Removes location updates from the FusedLocationApi.
*/
protected void stopLocationUpdates() {
// It is a good practice to remove location requests when the activity is in a paused or
// stopped state. Doing so helps battery performance and is especially
// recommended in applications that request frequent location updates.
LocationServices.FusedLocationApi.removeLocationUpdates(
mGoogleApiClient,
this
).setResultCallback(new ResultCallback<Status>() {
@Override
public void onResult(Status status) {
}
});
}
@Override
public void onConnected(@Nullable Bundle bundle) {
if (mCurrentLocation == null) {
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.
if (ActivityCompat.shouldShowRequestPermissionRationale(MapActivty.this, Manifest.permission.ACCESS_FINE_LOCATION)) {
//This is called if user has denied the permission before
//In this case I am just asking the permission again
ActivityCompat.requestPermissions(MapActivty.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 1);
} else {
ActivityCompat.requestPermissions(MapActivty.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 1);
}
return;
} else {
Toast.makeText(this, "" + permission + " is already granted.", Toast.LENGTH_SHORT).show();
}
mCurrentLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
//updateUI();
}
}
@Override
public void onConnectionSuspended(int i) {
Log.i("Map Activity", "Connection suspended");
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
Log.i("Map Activity", "Connection failed: ConnectionResult.getErrorCode() = " + connectionResult.getErrorCode());
}
@Override
public void onResult(@NonNull LocationSettingsResult locationSettingsResult) {
final Status status = locationSettingsResult.getStatus();
switch (status.getStatusCode()) {
case LocationSettingsStatusCodes.SUCCESS:
Log.i("Map ACtivity", "All location settings are satisfied.");
startLocationUpdates();
break;
case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
Log.i("Map ACtivity", "Location settings are not satisfied. Show the user a dialog to" +
"upgrade location settings ");
try {
// Show the dialog by calling startResolutionForResult(), and check the result
// in onActivityResult().
status.startResolutionForResult(MapActivty.this, REQUEST_CHECK_SETTINGS);
} catch (IntentSender.SendIntentException e) {
Log.i("Map ACtivity", "PendingIntent unable to execute request.");
}
break;
case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
Log.i("Map ACtivity", "Location settings are inadequate, and cannot be fixed here. Dialog " +
"not created.");
break;
}
}
@Override
public void onLocationChanged(Location location) {
mCurrentLocation = location;
//updateUI();
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
// Check for the integer request code originally supplied to startResolutionForResult().
case REQUEST_CHECK_SETTINGS:
switch (resultCode) {
case Activity.RESULT_OK:
Log.i("Map Activity", "User agreed to make required location settings changes.");
startLocationUpdates();
break;
case Activity.RESULT_CANCELED:
Log.i("Map Activity", "User chose not to make required location settings changes.");
break;
}
break;
}
}
@Override
public void onStart() {
super.onStart();
mGoogleApiClient.connect();
checkLocationSettings();
}
@Override
public void onResume() {
super.onResume();
// Within {@code onPause()}, we pause location updates, but leave the
// connection to GoogleApiClient intact. Here, we resume receiving
// location updates if the user has requested them.
if (mGoogleApiClient.isConnected()) {
startLocationUpdates();
}
}
@Override
protected void onPause() {
super.onPause();
// Stop location updates to save battery, but don't disconnect the GoogleApiClient object.
if (mGoogleApiClient.isConnected()) {
stopLocationUpdates();
}
}
@Override
public void onStop() {
super.onStop();
mGoogleApiClient.disconnect();
}
@Override
public void onMapReady(GoogleMap map) {
this.map = map;
map.setMapType(GoogleMap.MAP_TYPE_NORMAL);
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.
if (ActivityCompat.shouldShowRequestPermissionRationale(MapActivty.this, Manifest.permission.ACCESS_FINE_LOCATION)) {
//This is called if user has denied the permission before
//In this case I am just asking the permission again
ActivityCompat.requestPermissions(MapActivty.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 1);
} else {
ActivityCompat.requestPermissions(MapActivty.this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, 1);
}
return;
}
map.setMyLocationEnabled(true);
map.setTrafficEnabled(true);
map.setIndoorEnabled(true);
map.setBuildingsEnabled(true);
map.getUiSettings().setZoomControlsEnabled(true);
}
}
这是我的布局文件：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
tools:context="com.example.talarir.mapproject.NonAdminClasses.MapActivty">
<Button
android:id="@+id/buttonSaveLocationNonAdmin"
android:layout_width="wrap_content"
android:onClick="onClickTheSaveLocationButton"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:text="Save U!" />
<fragment
android:id="@+id/map"
android:name="com.google.android.gms.maps.MapFragment"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
</RelativeLayout>
我的ManiFest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.talarir.mapproject">
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="com.google.maps.android.utils.permission.MAPS_RECEIVE" />
<uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-feature
android:glEsVersion="0x00020000"
android:required="true" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
<meta-data
android:name="com.google.android.geo.API_KEY"
android:value="key" />
<activity android:name=".LoginActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".SignupActivity" />
<activity android:name=".AdminActivity" />
<activity android:name=".NonAdminACtivity" />
<activity android:name=".AdminClasses.AddMainGroupAdmin" />
<activity android:name=".AdminClasses.AddSubGroupAdmin" />
<activity android:name=".NonAdminClasses.MapActivty"></activity>
</application>
</manifest>
感谢提前：）
在onViewCreated中获得这样的许可
@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState){
super.onViewCreated(view, savedInstanceState);
supportMapFragment = SupportMapFragment.newInstance();
FragmentTransaction ft = getActivity().getSupportFragmentManager().beginTransaction().
replace(R.id.map, supportMapFragment);
ft.commit();
if ((ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED))
{
/*ActivityCompat.requestPermissions(getActivity(),new String[] {Manifest.permission.ACCESS_FINE_LOCATION,Manifest.permission
.ACCESS_COARSE_LOCATION},LOCATION_PERMISSION_REQUEST_CODE);*/
requestPermissions(new String[]{
Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION}, LOCATION_PERMISSION_REQUEST_CODE);
Log.d(TAG, "onViewCreated: in if");
} else {
supportMapFragment.getMapAsync(this);
Log.d(TAG, "onViewCreated: in else");
}
}
以及您的onRequestPermissionsResult
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (requestCode == LOCATION_PERMISSION_REQUEST_CODE)
{
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
supportMapFragment.getMapAsync(this);
} else if (grantResults.length==0)
{
if ((ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED))
{
requestPermissions(new String[]{
Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION}, LOCATION_PERMISSION_REQUEST_CODE);
}
}
}
在应用此代码之前，请检查您的OnRequestPermission方法是否正在调用并grantResults.length==0。这通常是在首次安装后发生]