Android key hashes not configured

Question

]2I implemented facebook login as mentioned in this link. I added my app in facebook's developer page, added hash key and got the app ID. On first run, app was able to log in successfully. But after that, when it comes to the facebook page, it shows error that "This app has no Android key hashes configured. Configure your app key hashes at http://developers.facebook.com/apps/. I don't know what the problem is as the hash key is already added in the facebook account.

Manifest

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.myfblogin"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />
    <uses-permission android:name="android.permission.INTERNET"/>

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <meta-data android:name="com.facebook.sdk.ApplicationId" android:value="@string/facebook_app_id"/>

        <activity android:name="com.facebook.FacebookActivity"
            android:configChanges="keyboard|keyboardHidden|screenLayout|screenSize|orientation"
            android:theme="@android:style/Theme.Translucent.NoTitleBar"
            android:label="@string/app_name" />
        <provider android:authorities="com.facebook.app.FacebookContentProvider<my app id>"
            android:name="com.facebook.FacebookContentProvider"
            android:exported="true"/>
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

Main Activity

public class MainActivity extends Activity {
    CallbackManager callbackManager;
    Button share,details;
    ShareDialog shareDialog;
    LoginButton login;
    ProfilePictureView profile;
    Dialog details_dialog;
    TextView details_txt;


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

        callbackManager = CallbackManager.Factory.create();
        login = (LoginButton)findViewById(R.id.login_button);
        profile = (ProfilePictureView)findViewById(R.id.picture);
        shareDialog = new ShareDialog(this);
        share = (Button)findViewById(R.id.share);
        details = (Button)findViewById(R.id.details);
        login.setReadPermissions("public_profile email");
        share.setVisibility(View.INVISIBLE);
        details.setVisibility(View.INVISIBLE);
        details_dialog = new Dialog(this);
        details_dialog.setContentView(R.layout.dialog_details);
        details_dialog.setTitle("Details");
        details_txt = (TextView)details_dialog.findViewById(R.id.details);
        details.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                details_dialog.show();
            }
        });


        if(AccessToken.getCurrentAccessToken() != null){
            RequestData();
            share.setVisibility(View.VISIBLE);
            details.setVisibility(View.VISIBLE);
        }
        login.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if(AccessToken.getCurrentAccessToken() != null) {
                    share.setVisibility(View.INVISIBLE);
                    details.setVisibility(View.INVISIBLE);
                    profile.setProfileId(null);
                }
            }
        });
        share.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                ShareLinkContent content = new ShareLinkContent.Builder().build();
                shareDialog.show(content);

            }
        });
        login.registerCallback(callbackManager, new FacebookCallback<LoginResult>() {
            @Override
            public void onSuccess(LoginResult loginResult) {

                if(AccessToken.getCurrentAccessToken() != null){
                    RequestData();
                    share.setVisibility(View.VISIBLE);
                    details.setVisibility(View.VISIBLE);
                }
            }

            @Override
            public void onCancel() {

            }

            @Override
            public void onError(FacebookException exception) {
            }
        });

    }
    public void RequestData(){
        GraphRequest request = GraphRequest.newMeRequest(AccessToken.getCurrentAccessToken(), new GraphRequest.GraphJSONObjectCallback() {
            @Override
            public void onCompleted(JSONObject object,GraphResponse response) {

                JSONObject json = response.getJSONObject();
                try {
                    if(json != null){
                        String text = "<b>Name :</b> "+json.getString("name")+"<br><br><b>Email :</b> "+json.getString("email")+"<br><br><b>Profile link :</b> "+json.getString("link");
                        details_txt.setText(Html.fromHtml(text));
                        profile.setProfileId(json.getString("id"));
                    }

                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        });
        Bundle parameters = new Bundle();
        parameters.putString("fields", "id,name,link,email,picture");
        request.setParameters(parameters);
        request.executeAsync();
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        callbackManager.onActivityResult(requestCode, resultCode, data);
    }

}

Answer 1

Add this in your Activity and get key in HashKey Log. Add this HashKey in you Facebook console.

public static void showHashKey(Context context) {

// Set Your Package Name                                                                                                                 
String m_PackageName = "com.example";

    try {
        PackageInfo info = context.getPackageManager().getPackageInfo(m_PackageName, PackageManager.GET_SIGNATURES); 
        for (Signature signature : info.signatures) {
            MessageDigest md = MessageDigest.getInstance("SHA");
            md.update(signature.toByteArray());
            Log.d("HashKey", Base64.encodeToString(md.digest(), Base64.DEFAULT));
        }
    } catch (NameNotFoundException e) {
        Log.d("HashKey", e.getMessage());

    } catch (NoSuchAlgorithmException e) {
        Log.d("HashKey", e.getMessage());

    }
}