Facebook SDK 4 for Android - how to log out programmatically

问题

Recently, Facebook released SDK 4 with new and cool updates. I tried to switch into SDK4 to use new features, however, I am struggling with the Login feature of Facebook.

So far, to log out Facebook programmatically, I used :

Session session = Session.getActiveSession();
session.closeAndClearTokenInformation();

But SDK4 seems not to support Session anymore, and in official docs, they mention:

There are two ways to implement Facebook login on Android:

LoginButton class - Which provides a button you can add to your UI. It follows the current access token and can log people in and out.

Well, seems there's no way to log out Facebook programmatically except using LoginButton. Anyone have any idea, please share it here.

回答1:

You can use LoginManager.getInstance().logOut();, even if you use LoginButton because

This UI element wraps functionality available in the LoginManager.

EDIT: Just to mention that this works for Facebook SDK v4. I don't know if they will change it in the future.

@as batoutofhell mention, don't forget to put FacebookSdk.sdkInitialize(getApplicationContext()); to initialize the facebook sdk. Please see here for the details.

回答2:

SDK4, if you want to completely de-couple, make sure you also remove the app from the user's facebook account. This method disconnects the user completely:

public void disconnectFromFacebook() {

    if (AccessToken.getCurrentAccessToken() == null) {
        return; // already logged out
    }

    new GraphRequest(AccessToken.getCurrentAccessToken(), "/me/permissions/", null, HttpMethod.DELETE, new GraphRequest
            .Callback() {
        @Override
        public void onCompleted(GraphResponse graphResponse) {

            LoginManager.getInstance().logOut();

        }
    }).executeAsync();
}

回答3:

You can use LoginManager.logOut()

Check out https://developers.facebook.com/docs/reference/android/current/class/LoginManager/

回答4:

To handle it with the loginButton:

//Check if user is currently logged in
        if (AccessToken.getCurrentAccessToken() != null && com.facebook.Profile.getCurrentProfile() != null){
            //Logged in so show the login button
            fbLogin.setVisibility(View.VISIBLE);
            fbLogin.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
//log out
                    LoginManager.getInstance().logOut();
                    gotoLogin();
                }
            });
        }

回答5:

You can logout by using LoginManager but you have to use graph request also. I am talking about log out completely so, that next time you can login with different account.

new GraphRequest(AccessToken.getCurrentAccessToken(), "/me/permissions/", null, HttpMethod.DELETE, new GraphRequest
            .Callback() {
        @Override
        public void onCompleted(GraphResponse graphResponse) {

            SharedPreferences pref = DashBoard.this.getPreferences(Context.MODE_PRIVATE);
            SharedPreferences.Editor editor = pref.edit();
            editor.clear();
            editor.commit();
            LoginManager.getInstance().logOut();

            Intent logoutint = new Intent(DashBoard.this,MainActivity.class);
            logoutint.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
               startActivity(logoutint);

        }
    }).executeAsync();

By the help of shared preferences here you can logout completely, and next time you can login with different account.

来源：https://stackoverflow.com/questions/29305232/facebook-sdk-4-for-android-how-to-log-out-programmatically