Question

我是Android Studio的新手，我尝试在第一个活动中使用Google登录按钮制作一个小型应用程序。在我点击Google登录按钮并选择帐户后，该应用程序会与登录按钮保持相同的活动，并且不会切换到下一个帐户。

我厌倦了更改google-services.json文件，但没有希望。

这是带有按钮的MainActivity

package routes.example.route;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

import com.google.android.gms.auth.api.signin.GoogleSignIn;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.gms.auth.api.signin.GoogleSignInClient;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.common.SignInButton;
import com.google.android.gms.common.api.ApiException;
import com.google.android.gms.tasks.Task;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    int RC_SIGN_IN = 0;
    SignInButton signInButton;
    GoogleSignInClient mGoogleSignInClient;

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

        signInButton = findViewById(R.id.sign_in_button);

        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestEmail()
                .build();

        mGoogleSignInClient = GoogleSignIn.getClient(this, gso);
        GoogleSignInAccount account = GoogleSignIn.getLastSignedInAccount(this);
        updateUI();
        findViewById(R.id.sign_in_button).setOnClickListener(this);
    }


    protected void updateUI(){
        GoogleSignInAccount account = GoogleSignIn.getLastSignedInAccount(this);
        if(account!=null){
            startActivity(new Intent(MainActivity.this, Main2Activity.class));
        }
        super.onStart();
    }
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.sign_in_button:
                signIn();
                break;
        }
    }
    private void signIn() {
        Intent signInIntent = mGoogleSignInClient.getSignInIntent();
        startActivityForResult(signInIntent, RC_SIGN_IN);
    }
    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        // Result returned from launching the Intent from GoogleSignInClient.getSignInIntent(...);
        if (requestCode == RC_SIGN_IN) {
            // The Task returned from this call is always completed, no need to attach
            // a listener.
            Task<GoogleSignInAccount> task = GoogleSignIn.getSignedInAccountFromIntent(data);
            handleSignInResult(task);
        }
    }
    private void handleSignInResult(Task<GoogleSignInAccount> completedTask) {
        try {
            GoogleSignInAccount account = completedTask.getResult(ApiException.class);

            // Signed in successfully, show authenticated UI.
            updateUI();
        } catch (ApiException e) {
            // The ApiException status code indicates the detailed failure reason.
            // Please refer to the GoogleSignInStatusCodes class reference for more information.
            updateUI();
        }
    }

}

这是登录按钮单击并选择帐户后以及登录期间logcat所显示的内容。

2019-07-23 09:10:18.413 8908-8908/routes.example.route D/HwCust: Create obj success use class android.app.HwCustActivityImpl
2019-07-23 09:10:18.415 8908-8908/routes.example.route D/HwCust: Create obj success use class android.app.HwCustHwWallpaperManagerImpl
2019-07-23 09:10:18.431 8908-10612/routes.example.route D/FA: Logging event (FE): user_engagement(_e), Bundle[{firebase_event_origin(_o)=auto, engagement_time_msec(_et)=624539, firebase_screen_class(_sc)=MainActivity, firebase_screen_id(_si)=190881185532362415}]
2019-07-23 09:10:18.445 8908-8908/routes.example.route D/ActivityThread: add activity client record, r= ActivityRecord{463f641 token=android.os.BinderProxy@2d1f2c5 {routes.example.route/com.google.android.gms.auth.api.signin.internal.SignInHubActivity}} token= android.os.BinderProxy@2d1f2c5
2019-07-23 09:10:18.451 8908-8920/routes.example.route I/zygote64: Do full code cache collection, code=124KB, data=103KB
2019-07-23 09:10:18.452 8908-8920/routes.example.route I/zygote64: After code cache collection, code=111KB, data=63KB
2019-07-23 09:10:18.453 8908-8978/routes.example.route D/OpenGLRenderer:   HWUI Binary is  enabled
2019-07-23 09:10:18.460 8908-8908/routes.example.route I/PressGestureDetector: onAttached begin
2019-07-23 09:10:18.461 8908-8908/routes.example.route I/PressGestureDetector: onAttached end
2019-07-23 09:10:18.462 8908-10613/routes.example.route I/PressGestureDetector: HiTouch restricted: AboardArea.
2019-07-23 09:10:18.478 8908-8978/routes.example.route D/mali_winsys: EGLint new_window_surface(egl_winsys_display *, void *, EGLSurface, EGLConfig, egl_winsys_surface **, egl_color_buffer_format *, EGLBoolean) returns 0x3000
2019-07-23 09:10:18.487 8908-10612/routes.example.route D/FA: Logging event (FE): screen_view(_vs), Bundle[{firebase_event_origin(_o)=auto, firebase_previous_class(_pc)=MainActivity, firebase_previous_id(_pi)=190881185532362415, firebase_screen_class(_sc)=SignInHubActivity, firebase_screen_id(_si)=190881185532362419}]
2019-07-23 09:10:18.534 8908-8978/routes.example.route D/OpenGLRenderer:   HWUI Binary is  enabled
2019-07-23 09:10:18.536 8908-8908/routes.example.route W/InputMethodManager: startInputReason = 1
2019-07-23 09:10:18.537 8908-8908/routes.example.route W/InputMethodManager: startInputOrWindowGainedFocus failed. Window focus may have already been lost. win=android.view.ViewRootImpl$W@6a02c79 view=DecorView@845ffd4[SignInHubActivity],focus=false,windowFocus=true,window=android.view.ViewRootImpl$W@6a02c79,temporaryDetach=false
2019-07-23 09:10:18.551 8908-10612/routes.example.route D/FA: Connected to remote service
2019-07-23 09:10:22.583 8908-8908/routes.example.route W/InputMethodManager: startInputReason = 1
2019-07-23 09:10:22.713 8908-8908/routes.example.route W/InputMethodManager: startInputReason = 1
2019-07-23 09:10:22.729 8908-8978/routes.example.route W/libEGL: EGLNativeWindowType 0x739775c010 disconnect failed
2019-07-23 09:10:22.730 8908-10612/routes.example.route D/FA: Logging event (FE): screen_view(_vs), Bundle[{firebase_event_origin(_o)=auto, firebase_previous_class(_pc)=SignInHubActivity, firebase_previous_id(_pi)=190881185532362419, firebase_screen_class(_sc)=MainActivity, firebase_screen_id(_si)=190881185532362415}]
2019-07-23 09:10:22.760 8908-8908/routes.example.route D/ActivityThread: Remove activity client record, r= ActivityRecord{463f641 token=android.os.BinderProxy@2d1f2c5 {routes.example.route/com.google.android.gms.auth.api.signin.internal.SignInHubActivity}} token= android.os.BinderProxy@2d1f2c5

Answer 1

在UpdateUI方法中，为什么要调用GoogleSignInAccount account = GoogleSignIn.getLastSignedInAccount(this);以及super.onStart（）？我不知道。

我认为您在handleSignInResult方法中遇到了例外情况

您需要优化几件事。

您是否在handleSignInResult方法中检查了任何异常？因为你在UpdateUI中也称为catch block
在handleSignInResult中，您获得了GoogleSignInAccount，可以在account方法中传递updateUI变量。
通过updateUI方法，您可以检查account参数是否为空，然后转到下一个活动。

代码时间： 更新您的updateUi方法：

protected void updateUI(GoogleSignInAccount account){

        if(account!=null){
            startActivity(new Intent(MainActivity.this, Main2Activity.class));
        }else{
  //Show alert that an exception occured.
}
        //super.onStart(); remove this line
    }

现在您必须修改以下方法：

private void handleSignInResult(Task<GoogleSignInAccount> completedTask) {
        try {
            GoogleSignInAccount account = completedTask.getResult(ApiException.class);

            // Signed in successfully, show authenticated UI.
            updateUI(account);
        } catch (ApiException e) {
           Log.d("ExceptionTag",e.getMessage());
            // Please check that you got any exception here or not.
            updateUI(null);
        }
    }

Answer 2

此代码很好用，祝您好运

public class MainActivity extends AppCompatActivity {

    int RC_SIGN_IN = 0;
    SignInButton signInButton;
    GoogleSignInClient mGoogleSignInClient;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        signInButton = findViewById(R.id.sign_in_button);
        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestEmail()
                .build();
        mGoogleSignInClient = GoogleSignIn.getClient(this,gso);
        signInButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                signIn();
            }
        });
    }

    private void signIn() {
        Intent signInIntent = mGoogleSignInClient.getSignInIntent();
        startActivityForResult(signInIntent,RC_SIGN_IN);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == RC_SIGN_IN){
            Task<GoogleSignInAccount> task = GoogleSignIn.getSignedInAccountFromIntent(data);
            handleSignInResult(task);
        }
    }

    private void handleSignInResult(Task<GoogleSignInAccount> completedTask) {
        try {
            GoogleSignInAccount account = completedTask.getResult(ApiException.class);
            startActivity(new Intent(MainActivity.this,Main2Activity.class));

        } catch (ApiException e) {

            Log.w("Google Sign In Error " , "signInResult:failed code : "  + e.getStatusCode());
            Toast.makeText(this, "Failed", Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    protected void onStart() {
        GoogleSignInAccount account = GoogleSignIn.getLastSignedInAccount(this);
        if (account != null){
            startActivity(new Intent(MainActivity.this,Main2Activity.class));
        }
        super.onStart();
    }
}

ClassTwo

public class Main2Activity extends AppCompatActivity {

    GoogleSignInClient mGoogleSignInClient;
    Button sign_out;
    TextView nameTV,emailTV,idTV;
    ImageView photoIV;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);

        sign_out = findViewById(R.id.log_out);
        nameTV = findViewById(R.id.name);
        emailTV = findViewById(R.id.email);
        idTV = findViewById(R.id.id);
        photoIV = findViewById(R.id.photo);

        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
        .requestEmail()
                .build();

        mGoogleSignInClient = GoogleSignIn.getClient(this,gso);
        GoogleSignInAccount acct = GoogleSignIn.getLastSignedInAccount(Main2Activity.this);

        if (acct != null){
            String personName = acct.getDisplayName();
            String personGivenName = acct.getGivenName();
            String personFamilyName = acct.getFamilyName();
            String personEmail = acct.getEmail();
            String personId = acct.getId();
            Uri personPhoto = acct.getPhotoUrl();

            nameTV.setText("Name : " + personName);
            emailTV.setText("Email : " + personEmail);
            idTV.setText("ID : " + personId);

            Glide.with(this).load(personPhoto).into(photoIV);

        }
        sign_out.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                signOut();
            }
        });
    }

    private void signOut() {
        mGoogleSignInClient.signOut()
               .addOnCompleteListener(this, new OnCompleteListener<Void>() {
                   @Override
                   public void onComplete(@NonNull Task<Void> task) {
                       Toast.makeText(Main2Activity.this, "Successfully signed out ", Toast.LENGTH_SHORT).show();
                       startActivity(new Intent(Main2Activity.this,MainActivity.class));
                       finish();
                   }
               });

    }

}

登录后，活动不会切换

2 个答案: