4.2 打开wifi

WifiManager wifiManager = (WifiManager) context.getSystemService(context.WIFI_SERVICE);

            Method[] methods = wifiManager.getClass().getDeclaredMethods();
            boolean enabled=false;
            for (Method method : methods) {
                if (method.getName().equals("isWifiApEnabled")) {
                    try {
                       enabled = (Boolean) method.invoke(wifiManager);
                    } catch (Exception ex) {
                    }
                    break;
                }
            }
            for (Method method : methods) {
                if (method.getName().equals("setWifiApEnabled")) {
                    try {
                        method.invoke(wifiManager, null, !enabled);
                    } catch (Exception ex) {
                    }
                    break;
                }
            }

 android.permission.CHANGE_WIFI_STATE