在webview中设置代理

在android1.6之前的api中有有直接的方法来对webview设置代码，但是在之后的API中去掉了。所以只能寻求别的方法来设置代码。

下面代码是用反射原理来对webview设置代理：

    public static boolean setProxy(Context ctx, String host, int port) {        boolean ret = false;        try {            Log.d("WebViewProxySettings", "setProxy defaulthost="+host+"port="+port);            Object requestQueueObject = getRequestQueue(ctx);            if (requestQueueObject != null) {                //Create Proxy config object and set it into request Q                HttpHost httpHost = new HttpHost(host, port, "http");                setDeclaredField(requestQueueObject, "mProxyHost", httpHost);                ret = true;            }        } catch (Exception e) {            e.printStackTrace();        }        return ret;    }            public static String getProxyHostname(Context ctx){    String res = null;    try {            Object requestQueueObject = getRequestQueue(ctx);            if (requestQueueObject != null) {            Object fild = getDeclaredField(requestQueueObject,"mProxyHost");            if(fild!=null){            HttpHost host = (HttpHost)fild;            res = host.getHostName();            }            }     } catch (Exception e) {             e.printStackTrace();         }        return res;    }    public static void cancelProxy(Context ctx){    try {        Object requestQueueObject = getRequestQueue(ctx);        if (requestQueueObject != null) {            setDeclaredField(requestQueueObject, "mProxyHost", null);        }    } catch (Exception e) {            e.printStackTrace();        }    }    public static Object getRequestQueue(Context ctx) throws Exception {        Object ret = null;        Class networkClass = Class.forName("android.webkit.Network");        if (networkClass != null) {            Object networkObj = invokeMethod(networkClass, "getInstance", new Object[]{ctx}, Context.class);            if (networkObj != null) {                ret = getDeclaredField(networkObj, "mRequestQueue");            }        }        return ret;    }    private static Object getDeclaredField(Object obj, String name)            throws SecurityException, NoSuchFieldException,            IllegalArgumentException, IllegalAccessException {        Field f = obj.getClass().getDeclaredField(name);        f.setAccessible(true);        Object out = f.get(obj);        //System.out.println(obj.getClass().getName() + "." + name + " = "+ out);        return out;    }    private static void setDeclaredField(Object obj, String name, Object value)            throws SecurityException, NoSuchFieldException,            IllegalArgumentException, IllegalAccessException {        Field f = obj.getClass().getDeclaredField(name);        f.setAccessible(true);        f.set(obj, value);    }    private static Object invokeMethod(Object object, String methodName, Object[] params, Class... types) throws Exception {        Object out = null;        Class c = object instanceof Class ? (Class) object : object.getClass();        if (types != null) {            Method method = c.getMethod(methodName, types);            out = method.invoke(object, params);        } else {            Method method = c.getMethod(methodName);            out = method.invoke(object);        }        //System.out.println(object.getClass().getName() + "." + methodName + "() = "+ out);        return out;    }