@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    
    // Add code to print out the key hash
    try {
        PackageInfo info = getPackageManager().getPackageInfo(
                "com.facebook.samples.hellofacebook", 
                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 (NameNotFoundException e) {
        
    } catch (NoSuchAlgorithmException e) {
        
    }
    
    ...

保存更改并重新运行示例。检查你的logcat输出是否有类似这样的消息:

D/KeyHash:(936): 478uEnKQV+fMQT8Dy4AKvHkYibo=

将密钥哈希保存在开发人员配置文件中。重新运行示例并验证可以成功登录。

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。

请试试这个，它对我有用:

fun Context.generateSignKeyHash(): String {

    try {

        val info = packageManager.getPackageInfo(
            packageName,
            PackageManager.GET_SIGNATURES
        )

        for (signature in info.signatures) {
            val md = MessageDigest.getInstance("SHA")
            md.update(signature.toByteArray())
            return Base64.encodeToString(md.digest(), Base64.DEFAULT)
        }

    } catch (e: Exception) {
        Log.e("keyHash", e.message.toString())
    }

    return ""

}

在你的应用程序中运行:

FacebookSdk.sdkInitialize(getApplicationContext());
Log.d("AppLog", "key:" + FacebookSdk.getApplicationSignature(this)+"=");

或:

public static void printHashKey(Context context) {
    try {
        final PackageInfo info = context.getPackageManager().getPackageInfo(context.getPackageName(), PackageManager.GET_SIGNATURES);
        for (android.content.pm.Signature signature : info.signatures) {
            final MessageDigest md = MessageDigest.getInstance("SHA");
            md.update(signature.toByteArray());
            final String hashKey = new String(Base64.encode(md.digest(), 0));
            Log.i("AppLog", "key:" + hashKey + "=");
        }
    } catch (Exception e) {
        Log.e("AppLog", "error:", e);
    }
}

然后看看日志。

结果应该以“=”结尾。

解是基于这里和这里。

为了在你的本地计算机上生成你的密钥散列，运行Java的keytool实用程序(它应该在你的控制台路径上)针对Android调试密钥存储库。默认情况下，在你的home .android目录下)。在OS X上运行:

keytool -exportcert -alias androiddebugkey -keystore ~/.android/debug.keystore | openssl sha1 -binary | openssl base64

Windows操作系统使用:-

keytool -exportcert -alias androiddebugkey -keystore %HOMEPATH%\.android\debug.keystore | openssl sha1 -binary | openssl base64

希望这对你有所帮助

参考开发者facebook网站

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。