Android.hardware.USB類介紹

        在最新的Android版本中，android.hardware.USB是一個新增類，提供了USB相關事件的插拔，以及狀態模式的廣播。這裡，可以看到USB連接、斷開、是否為U盤、ADB模式等等。定義如下

java代碼：
public class Usb {

public static final String ACTION_USB_CONNECTED ="android.hardware.action.USB_CONNECTED";
public static final String ACTION_USB_DISCONNECTED ="android.hardware.action.USB_DISCONNECTED";

public static final String ACTION_USB_STATE =
"android.hardware.action.USB_STATE";

public static final String USB_CONNECTED = "connected";
public static final String USB_FUNCTION_MASS_STORAGE = "mass_storage";
public static final String USB_FUNCTION_ADB = "adb";
public static final String USB_FUNCTION_RNDIS = "rndis";
public static final String USB_FUNCTION_MTP = "mtp";
public static final String USB_FUNCTION_ENABLED = "enabled";
public static final String USB_FUNCTION_DISABLED = "disabled";