请试试这个:

public static void printHashKey(Context pContext) {
        try {
            PackageInfo info = pContext.getPackageManager().getPackageInfo(pContext.getPackageName(), PackageManager.GET_SIGNATURES);
            for (Signature signature : info.signatures) {
                MessageDigest md = MessageDigest.getInstance("SHA");
                md.update(signature.toByteArray());
                String hashKey = new String(Base64.encode(md.digest(), 0));
                Log.i(TAG, "printHashKey() Hash Key: " + hashKey);
            }
        } catch (NoSuchAlgorithmException e) {
            Log.e(TAG, "printHashKey()", e);
        } catch (Exception e) {
            Log.e(TAG, "printHashKey()", e);
        }
    }

Windows:

打开命令提示符并粘贴下面的命令

键盘出口，又名仙女座键盘 HOMEPATH % \调试机器人。keystore | openssl sha1 -binary | openssl base64

输入密码:android——>按Enter键 用你的开发者账号登录Facebook 去你的Facebook应用程序>设置>粘贴哈希键在“键哈希”选项>保存更改。 现在用Facebook登录/分享等测试你的android应用。

这就是我如何获得我的:

private class SessionStatusCallback implements Session.StatusCallback {
        @Override
        public void call(Session session, SessionState state, Exception exception) {

            if (exception != null) {
                new AlertDialog.Builder(FriendActivity.this)
                        .setTitle(R.string.login_failed_dialog_title)
                        .setMessage(exception.getMessage())
                        .setPositiveButton(R.string.ok_button, null)
                        .show();
            }

因此，当您试图在没有密钥的情况下输入时，将会出现异常。Facebook在这个例外中加入了RIGHT键。你所要做的就是复制它。

如果你已经将应用程序上传到Play商店，你可以生成哈希密钥如下:

点击这里进入发布管理 选择“发布管理->应用签名” 你可以看到SHA1密钥十六进制格式的App签名证书。 复制十六进制格式的SHA1，并将其转换为base64格式，你可以使用这个链接做到没有SHA1:十六进制的一部分。 转到Facebook开发者控制台，在设置- > basic - > key哈希值中添加键(转换为base64后)。

https://developers.facebook.com/docs/android/getting-started/

4.19.0 - 2017年1月25日

Facebook SDK

修改

Facebook SDK现在在应用程序启动时自动初始化。在大多数情况下，不再需要手动调用FacebookSDK.sdkInitialize()。有关详细信息，请参见升级指南。

为调试

try {
    PackageInfo info = getPackageManager().getPackageInfo(getPackageName(), PackageManager.GET_SIGNATURES);
    for (Signature signature : info.signatures) {
        MessageDigest md = MessageDigest.getInstance("SHA");
        md.update(signature.toByteArray());
        Log.d("KeyHash:", Base64.encodeToString(md.digest(), Base64.DEFAULT));
    }
} catch (NoSuchAlgorithmException e) {
    e.printStackTrace();
} catch (Exception e) {
    e.printStackTrace();
}

this will help newbees also. just adding more details to @coder_For_Life22's answer. if this answer helps you don't forget to upvote. it motivates us. for this you must already know the path of the app's keystore file and password for this example consider the key is stored at "c:\keystorekey\new.jks" 1. open this page https://code.google.com/archive/p/openssl-for-windows/downloads 2. download 32 or 64 bit zip file as per your windows OS. 3. extract the downloaded file where ever you want and remember the path. 4. for this example we consider that you have extracted the folder in download folder. so the file address will be "C:\Users\0\Downloads\openssl-0.9.8e_X64\bin\openssl.exe"; 5. now on keyboard press windows+r button. 6. this will open run box. 7. type cmd and press Ctrl+Shift+Enter. 8. this will open command prompt as administrator. 9. here navigate to java's bin folder: if you use jre provided by Android Studio you will find the path as follows: a. open android studio. b. file->project structure c. in the left pane, click 'SDK location' d. in the right pane, below 'JDK location' is your jre path. e. add "\bin" at the end of this path as the file "keytool.exe", we need, is inside this folder. for this example i consider, you have installed java separately and following is the path "C:\Program Files\Java\jre-10.0.2\bin" if you have installed 32bit java it will be in "C:\Program Files (x86)\Java\jre-10.0.2\bin" 10. now with above paths execute command as following:

keytool -exportcert -alias androiddebugkey -keystore "c:\keystorekey\new.jks" | "C:\Users\0\Downloads\openssl-0.9.8e_X64\bin\openssl.exe" sha1 -binary |"C:\Users\0\Downloads\openssl-0.9.8e_X64\bin\openssl.exe" base64

您将被要求输入密码，请输入您在创建密钥存储库密钥时所提供的密码。 ! ! 这将给你钥匙

错误: 如果你得到: --- 'keytool'不能被识别为内部或外部命令 --- 这意味着Java安装在其他地方。