c# - 以编程方式打开/关闭 WiFi 热点

Question

我需要帮助创建一个在热点模式下设置 android WiFi 的 C# 脚本。这是我设法创建的代码。

    public bool setAPEnabled(bool enabled)
{
    using (AndroidJavaObject activity = new AndroidJavaClass("com.unity3d.player.UnityPlayer").GetStatic<AndroidJavaObject>("currentActivity"))
    {
        try
        {
            if(isWifiEnabled()==true){
                setWifiEnabled(false);
            }
            using (var wifiManager = activity.Call<AndroidJavaObject>("getSystemService", "wifi"))
            {
                return wifiManager.Call<bool>("setWifiApEnabled",null, enabled);
            }
        }
        catch (Exception e)
        {
        }
    }
    return false;
}

一切正常 - 但我在设置 SSID 和密码时遇到问题。审查后documentation我知道我必须用设置对象替换我的空值，但我完全不知道如何在 Unity 中执行此操作。

Answer 1

这些方法仅适用于 android 5.0 及更低版本!

简单方式:

尝试实例化 WifiConfiguration第一:

AndroidJavaObject wifiConfiguration = new AndroidJavaClass("android.net.wifi.WifiConfiguration");

现在您可以在该对象中调用方法和设置/获取字段:

// to set SSID
wifiConfiguration.Set("SSID", meSSID); // string
wifiConfiguration.Set("preSharedKey", mePassword); // string

设置所有必填字段后，只需调用您的 setWifiApEnabled 方法:

wifiManager.Call<bool>("setWifiApEnabled", wifiConfiguration, enabled);

也许您必须设置比这两个更多的字段，但要确认您应该检查 source并确保 setWifiApEnabled 方法在内部执行的操作。

---

困难方式:
(使用反射代码)

第 6 步不适用于 android 5.0+!

在 AndroidJavaObject 中使用反射可能有点棘手，因为您必须记住释放每个对象。

所以从头开始:

// android code for that should look like :
// wifiManager.getClass().getMethod("setWifiApEnabled", WifiConfiguration.class, boolean.class);

// but in Unity C# you have to split this into few chunks:
// 1. Get calling class :
using ( AndroidJavaObject classObj = wifiManager.Call<AndroidJavaObject>("getClass") )
{
    // classObj should contains your class object 
    // 2. call get WifiConfiguration class details :
    using ( AndroidJavaObject wifiConfiguration = new AndroidJavaObject("setWifiApEnabled") )
    {
        // 3. Fill that object :
        wifiConfiguration.Set("SSID", meSSID); // string
        wifiConfiguration.Set("preSharedKey", mePassword); // string
        // 4. Get WifiConfiguration class definition
        using (AndroidJavaObject wifiCfgClass = wifiConfiguration.Call<AndroidJavaObject>("getClass") )
        { 
            // 5. Get boolean definition
            using ( AndroidJavaObject booleanObj = new AndroidJavaObject("java.lang.Boolean") )
            {
                using ( AndroidJavaObject booleanClass = booleanObj.Call<AndroidJavaObject>("getClass") )
                // 6. Get method definition
                using ( AndroidJavaObject methodObj = classObj.Call<AndroidJavaObject>("getMethod", "setWifiApEnabled", wifiCfgClass , booleanClass))
                {
                    // 7. Call that method :)
                    methodObj.Call("invoke", wifiManager, wifiConfiguration, enabled);
                }
            }
        }
    }
}

---

Wifi 配置:

我试图找出为什么上面的代码可能无法工作，但对我来说它工作正常(在一些虚拟机和 Samsung Galaxy S5 Neo 上测试过)。

可能是什么情况(我在将近午夜时发现)是一个密码。
根据this wikipedia article在关于 WPA-PSK

的部分

Also referred to as WPA-PSK (pre-shared key) mode, this is designed for home and small office networks and doesn't require an authentication server.[9] Each wireless network device encrypts the network traffic using a 256 bit key. This key may be entered either as a string of 64 hexadecimal digits, or as a passphrase of 8 to 63 printable ASCII characters.[10] If ASCII characters are used, the 256 bit key is calculated by applying the PBKDF2 key derivation function to the passphrase, using the SSID as the salt and 4096 iterations of HMAC-SHA1.[11] WPA-Personal mode is available with both WPA and WPA2.)

我的建议是使用与上面链接的文章中相同的密码以确保其有效。

另外要注意的是 SSID 部分，它有一个简短但很好的描述 here on wikipedia .

A common, albeit incorrect assumption, is that an SSID is a string of human-readable characters (such as ASCII), terminated by a NUL character (as in a C-string). SSIDs must be treated and handled as what they are, a sequence of 0–32 octets, some of which may not be human-readable

根据我的检查，您不需要在 Java 或 C# 中以空字符终止您的字符串，因为它将由 native 代码处理，但您仍然不应超过 31 个字符(32 将是空字符)。

我检查了这个:
SSID:MeHotSpot
WPA-PSK:5260305714217573