你可以从Java/Kotlin Activity中打印哈希键。部分代码已弃用，但这里是包含新旧代码的完整解决方案。

private fun printHashKey(context: Context) {
    try {

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
            val packageInfo: PackageInfo = context.packageManager.getPackageInfo(
                context.packageName,
                PackageManager.GET_SIGNING_CERTIFICATES
            )

            for (signature in packageInfo.signingInfo.apkContentsSigners) {
                val md = MessageDigest.getInstance("SHA")
                md.update(signature.toByteArray())
                Log.d("KeyHash:", Base64.encodeToString(md.digest(), Base64.DEFAULT))
            }
        } else {
            val packageInfo: PackageInfo = context.packageManager.getPackageInfo(
                context.packageName,
                PackageManager.GET_SIGNATURES
            )

            for (signature in packageInfo.signatures) {
                val md = MessageDigest.getInstance("SHA")
                md.update(signature.toByteArray())
                Log.d("KeyHash:", Base64.encodeToString(md.digest(), Base64.DEFAULT))
            }
        }

    } catch (e: PackageManager.NameNotFoundException) {
        Log.d(TAG, "printHashKey: PackageManager.NameNotFoundException -> $e")
    } catch (e: NoSuchAlgorithmException) {
        Log.d(TAG, "printHashKey: NoSuchAlgorithmException -> $e")
    }
}

我找到的最简单的解决方法是:

打开原木猫 尝试使用Android SDK访问Facebook 在日志中寻找这样的行: 04-24 01:14:08.605: I/System.out(31395): invalid_key:Android key mismatch。 您的密钥“abcdefgHIJKLMN+OPqrstuvwzyz”与您的 应用程序设置。检查您的应用程序设置 http://www.facebook.com/developers 复制“abcdefgHIJKLMN+OPqrstuvwzyz”，并将其粘贴到Facebook Android密钥哈希区。

以下是步骤

Download openssl from Google code (If you have a 64 bit machine you must download openssl-0.9.8e X64 not the latest version) Extract it. create a folder- OpenSSL in C:/ and copy the extracted code here. detect debug.keystore file path. If u didn't find, then do a search in C:/ and use the Path in the command in next step. detect your keytool.exe path and go to that dir/ in command prompt and run this command in 1 line- $ keytool -exportcert -alias androiddebugkey -keystore "C:\Documents and Settings\Administrator.android\debug.keystore" | "C:\OpenSSL\bin\openssl" sha1 -binary |"C:\OpenSSL\bin\openssl" base64 it will ask for password, put android that's all. u will get a key-hash

欲了解更多信息，请访问这里

最好的方法是使用以下代码:

private void getHashKey(String pkgName)
{
    try
    {
        PackageInfo info = getPackageManager().getPackageInfo(pkgName, PackageManager.GET_SIGNATURES);
        for (Signature signature : info.signatures)
        {
            MessageDigest md = MessageDigest.getInstance("SHA");
            md.update(signature.toByteArray());
            String hashKey = Base64.encodeBytes(md.digest());
            _hashKey_et.setText(hashKey);
            Log.i("KeyTool", pkgName + " -> hashKey = " + hashKey);
        }
    }
    catch (NameNotFoundException e)
    {
        e.printStackTrace();
    }
    catch (NoSuchAlgorithmException e)
    {
        e.printStackTrace();
    }
}

但我很沮丧，因为没有简单的工具来为Facebook应用程序生成HashKey。每次我都必须使用Openssl和Keytool，或者使用代码从签名中获得哈希值……

所以我写了一个简单的KeyGenTool，将为您做这项工作:-> KeyGenTool谷歌播放<-

享受:)

这是Xamarin的版本

private void printKeyHash()
{
    try
    {
        PackageInfo info = PackageManager.GetPackageInfo(PackageName, PackageInfoFlags.Signatures);
        foreach (var signature in info.Signatures)
        {
            MessageDigest md = MessageDigest.GetInstance("SHA1");
            md.Update(signature.ToByteArray());
            var hash = Base64.EncodeToString(md.Digest(), Base64Flags.Default);
            Log.Debug("KeyHash:", hash);
        }
    }
    catch (PackageManager.NameNotFoundException e)
    {

    }
    catch (NoSuchAlgorithmException e)
    {

    }
}

This required no coding input. Go to Android Studio-> 
Click on Right side panel "Gradle"=>
*Your App Name =>
*Your App Name(root)=>
*Tasks=>
*android =>
*Double click on **signinReport**=>
Will get 
example :
SHA1: [![6A:DE:ED:5A:9F:0B:19:47:38:DC:DE:3B:7B:A2:D7:4C:6C:0A:24:70][1]][1]

Go to 

http://fbkeyhash.com/index.php
Paste your SHA-1