我在我的应用中集成了谷歌登录，适用于L和M设备。但由于某些原因不在KitKat及以下。我调试了它，它总是调用onConnectionFailed，但为什么呢？以下是LoginActivity：
public class LoginActivity extends AppCompatActivity implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
btn_google = (CircleButton) findViewById(R.id.btn_login_google);
btn_google.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (!mGoogleApiClient.isConnecting()) {
mShouldResolve = true;
resolveSignInError();
}
}
});
//Build GoogleApiClient
mGoogleApiClient = new GoogleApiClient.Builder(this).addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(Plus.API)
.addScope(new Scope(Scopes.PROFILE))
.addScope(new Scope(Scopes.EMAIL))
.addScope(new Scope(Scopes.PLUS_LOGIN))
.addScope(new Scope(Scopes.PLUS_ME))
.build();
mGoogleApiClient.connect();
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == RC_SIGN_IN) {
if (resultCode != RESULT_OK) {
mShouldResolve = false;
}
mIntentInProgress = false;
if (!mGoogleApiClient.isConnecting()) {
mGoogleApiClient.connect();
}
}
}
protected void onStart() {
super.onStart();
//connect GoogleApiClient
mGoogleApiClient.connect();
}
protected void onStop() {
super.onStop();
//disconnect GoogleApiClient
if (mGoogleApiClient.isConnected()) {
mGoogleApiClient.disconnect();
}
}
/*
Used for resolving errors during signIn
*/
private void resolveSignInError() {
if (connectionResult.hasResolution()) {
try {
mIntentInProgress = true;
connectionResult.startResolutionForResult(this, RC_SIGN_IN);
} catch (IntentSender.SendIntentException e) {
mIntentInProgress = false;
mGoogleApiClient.connect();
}
}
}
/*
When the GoogleApiClient object is unable to establish a connection onConnectionFailed() is called
*/
@Override
public void onConnectionFailed(ConnectionResult result) {
if (!result.hasResolution()) {
GooglePlayServicesUtil.getErrorDialog(result.getErrorCode(), this,
0).show();
return;
}
if (!mIntentInProgress) {
connectionResult = result;
if (mShouldResolve) {
resolveSignInError();
}
}
}
/*
on the successfull connection onConnected is called
*/
@Override
public void onConnected(Bundle arg0) {
mShouldResolve = false;
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
checkLocationPermission();
}else{
get_user_details();
}
}
private void get_user_details(){
try {
if (Plus.PeopleApi.getCurrentPerson(mGoogleApiClient) != null) {
Person person = Plus.PeopleApi
.getCurrentPerson(mGoogleApiClient);
personName_google = person.getDisplayName();
email_google = Plus.AccountApi.getAccountName(mGoogleApiClient);
} else {
}
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public void onConnectionSuspended(int arg0) {
mGoogleApiClient.connect();
}
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 100;
public boolean checkLocationPermission() {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.GET_ACCOUNTS)
!= PackageManager.PERMISSION_GRANTED) {
// Asking user if explanation is needed
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.GET_ACCOUNTS)) {
// Show an explanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
//Prompt the user once explanation has been shown
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.GET_ACCOUNTS},
MY_PERMISSIONS_REQUEST_LOCATION);
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.GET_ACCOUNTS},
MY_PERMISSIONS_REQUEST_LOCATION);
}
return false;
} else {
return true;
}
}
@Override
public void onRequestPermissionsResult(int requestCode,String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted. Do the
// contacts-related task you need to do.
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.GET_ACCOUNTS)
== PackageManager.PERMISSION_GRANTED) {
get_user_details();
}
} else {
// Permission denied, Disable the functionality that depends on this permission.
Toast.makeText(this, "permission denied", Toast.LENGTH_LONG).show();
dialog_general_prog.dismiss();
}
return;
}
}
}
}