一个可能的解决方案是在应用程序中编码数据，并在运行时(当你想使用该数据时)使用解码。我还建议使用progaard来增加应用程序反编译源代码的阅读和理解难度。例如，我把一个编码的密钥在应用程序，然后使用解码方法在我的应用程序解码我的秘密密钥在运行时:

// "the real string is: "mypassword" "; 
//encoded 2 times with an algorithm or you can encode with other algorithms too
public String getClientSecret() {
    return Utils.decode(Utils
            .decode("Ylhsd1lYTnpkMjl5WkE9PQ=="));
}

一个受保护的应用程序的反编译源代码如下:

 public String c()
 {
    return com.myrpoject.mypackage.g.h.a(com.myrpoject.mypackage.g.h.a("Ylhsd1lYTnpkMjl5WkE9PQ=="));
  }

至少对我来说够复杂了。当我别无选择只能在我的应用程序中存储一个值时，我就是这样做的。当然我们都知道这不是最好的方法，但对我来说很管用。

/**
 * @param input
 * @return decoded string
 */
public static String decode(String input) {
    // Receiving side
    String text = "";
    try {
        byte[] data = Decoder.decode(input);
        text = new String(data, "UTF-8");
        return text;
    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    }
    return "Error";
}

反编译版本:

 public static String a(String paramString)
  {
    try
    {
      str = new String(a.a(paramString), "UTF-8");
      return str;
    }
    catch (UnsupportedEncodingException localUnsupportedEncodingException)
    {
      while (true)
      {
        localUnsupportedEncodingException.printStackTrace();
        String str = "Error";
      }
    }
  }

你可以在谷歌中找到这么多的加密类。

很少有想法，在我看来，只有第一个想法给了一些保证:

Keep your secrets on some server on internet, and when needed just grab them and use. If user is about to use dropbox then nothing stops you from making request to your site and get your secret key. Put your secrets in jni code, add some variable code to make your libraries bigger and more difficult to decompile. You might also split key string in few parts and keep them in various places. use obfuscator, also put in code hashed secret and later on unhash it when needed to use. Put your secret key as last pixels of one of your image in assets. Then when needed read it in your code. Obfuscating your code should help hide code that will read it.

如果你想快速看看阅读你的apk代码是多么容易，然后获取APKAnalyser:

http://developer.sonymobile.com/knowledge-base/tool-guides/analyse-your-apks-with-apkanalyser/

将秘密保存在firebase数据库中，并在应用程序启动时从中获取， 它比调用web服务好得多。

As it is, your compiled application contains the key strings, but also the constant names APP_KEY and APP_SECRET. Extracting keys from such self-documenting code is trivial, for instance with the standard Android tool dx. You can apply ProGuard. It will leave the key strings untouched, but it will remove the constant names. It will also rename classes and methods with short, meaningless names, where ever possible. Extracting the keys then takes some more time, for figuring out which string serves which purpose. Note that setting up ProGuard shouldn't be as difficult as you fear. To begin with, you only need to enable ProGuard, as documented in project.properties. If there are any problems with third-party libraries, you may need to suppress some warnings and/or prevent them from being obfuscated, in proguard-project.txt. For instance: -dontwarn com.dropbox.** -keep class com.dropbox.** { *; } This is a brute-force approach; you can refine such configuration once the processed application works. You can obfuscate the strings manually in your code, for instance with a Base64 encoding or preferably with something more complicated; maybe even native code. A hacker will then have to statically reverse-engineer your encoding or dynamically intercept the decoding in the proper place. You can apply a commercial obfuscator, like ProGuard's specialized sibling DexGuard. It can additionally encrypt/obfuscate the strings and classes for you. Extracting the keys then takes even more time and expertise. You might be able to run parts of your application on your own server. If you can keep the keys there, they are safe.

In the end, it's an economic trade-off that you have to make: how important are the keys, how much time or software can you afford, how sophisticated are the hackers who are interested in the keys, how much time will they want to spend, how much worth is a delay before the keys are hacked, on what scale will any successful hackers distribute the keys, etc. Small pieces of information like keys are more difficult to protect than entire applications. Intrinsically, nothing on the client-side is unbreakable, but you can certainly raise the bar.

(我是ProGuard和DexGuard的开发者)

旧的不安全的方式:

遵循3个简单的步骤来保护API/密钥(旧答案)

我们可以使用Gradle来保护API密钥或秘密密钥。

1. gradle。properties(项目属性):创建带有key的变量。

GoogleAPIKey = "Your API/Secret Key"

2. 构建。gradle (Module: app):在build中设置变量。Gradle在活动或片段中访问它。将以下代码添加到buildTypes{}。

buildTypes.each {
    it.buildConfigField 'String', 'GoogleSecAPIKEY', GoolgeAPIKey
}

3.通过应用程序的BuildConfig在Activity/Fragment中访问它:

BuildConfig.GoogleSecAPIKEY

更新:

上述解决方案对通过Git提交的开源项目很有帮助。(感谢David Rawson和riyazi -ali的评论)。

根据Matthew和Pablo Cegarra的评论，上述方式是不安全的，反编译器将允许某人使用我们的密钥查看BuildConfig。

解决方案:

我们可以使用NDK来保护API密钥。我们可以在原生C/ c++类中存储键，并在Java类中访问它们。

请跟随这个博客使用NDK保护API密钥。

关于如何在Android中安全地存储令牌的后续内容

一个可能的解决方案是在应用程序中编码数据，并在运行时(当你想使用该数据时)使用解码。我还建议使用progaard来增加应用程序反编译源代码的阅读和理解难度。例如，我把一个编码的密钥在应用程序，然后使用解码方法在我的应用程序解码我的秘密密钥在运行时:

// "the real string is: "mypassword" "; 
//encoded 2 times with an algorithm or you can encode with other algorithms too
public String getClientSecret() {
    return Utils.decode(Utils
            .decode("Ylhsd1lYTnpkMjl5WkE9PQ=="));
}

一个受保护的应用程序的反编译源代码如下:

 public String c()
 {
    return com.myrpoject.mypackage.g.h.a(com.myrpoject.mypackage.g.h.a("Ylhsd1lYTnpkMjl5WkE9PQ=="));
  }

至少对我来说够复杂了。当我别无选择只能在我的应用程序中存储一个值时，我就是这样做的。当然我们都知道这不是最好的方法，但对我来说很管用。

/**
 * @param input
 * @return decoded string
 */
public static String decode(String input) {
    // Receiving side
    String text = "";
    try {
        byte[] data = Decoder.decode(input);
        text = new String(data, "UTF-8");
        return text;
    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    }
    return "Error";
}

反编译版本:

 public static String a(String paramString)
  {
    try
    {
      str = new String(a.a(paramString), "UTF-8");
      return str;
    }
    catch (UnsupportedEncodingException localUnsupportedEncodingException)
    {
      while (true)
      {
        localUnsupportedEncodingException.printStackTrace();
        String str = "Error";
      }
    }
  }

你可以在谷歌中找到这么多的加密类。