UsbAccessory
public
class
UsbAccessory
extends Object
implements
Parcelable
java.lang.Object | |
↳ | android.hardware.usb.UsbAccessory |
A class representing a USB accessory, which is an external hardware component that communicates with an android application over USB. The accessory is the USB host and android the device side of the USB connection.
When the accessory connects, it reports its manufacturer and model names, the version of the accessory, and a user visible description of the accessory to the device. The manufacturer, model and version strings are used by the USB Manager to choose an appropriate application for the accessory. The accessory may optionally provide a unique serial number and a URL to for the accessory's website to the device as well.
An instance of this class is sent to the application via the
UsbManager#ACTION_USB_ACCESSORY_ATTACHED
Intent.
The application can then call UsbManager#openAccessory
to open a file descriptor
for reading and writing data to and from the accessory.
Developer Guides
For more information about communicating with USB hardware, read the USB developer guide.
Summary
Inherited constants |
---|
Fields | |
---|---|
public
static
final
Creator<UsbAccessory> |
CREATOR
|
Public methods | |
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int
|
describeContents()
Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. |
boolean
|
equals(Object obj)
Indicates whether some other object is "equal to" this one. |
String
|
getDescription()
Returns a user visible description of the accessory. |
String
|
getManufacturer()
Returns the manufacturer name of the accessory. |
String
|
getModel()
Returns the model name of the accessory. |
String
|
getSerial()
Returns the unique serial number for the accessory. |
String
|
getUri()
Returns the URI for the accessory. |
String
|
getVersion()
Returns the version of the accessory. |
int
|
hashCode()
Returns a hash code value for the object. |
String
|
toString()
Returns a string representation of the object. |
void
|
writeToParcel(Parcel parcel, int flags)
Flatten this object in to a Parcel. |
Inherited methods | |
---|---|
Fields
Public methods
describeContents
public int describeContents ()
Describe the kinds of special objects contained in this Parcelable
instance's marshaled representation. For example, if the object will
include a file descriptor in the output of writeToParcel(android.os.Parcel, int)
,
the return value of this method must include the
CONTENTS_FILE_DESCRIPTOR
bit.
Returns | |
---|---|
int |
a bitmask indicating the set of special object types marshaled
by this Parcelable object instance.
Value is either 0 or CONTENTS_FILE_DESCRIPTOR |
equals
public boolean equals (Object obj)
Indicates whether some other object is "equal to" this one.
The equals
method implements an equivalence relation
on non-null object references:
- It is reflexive: for any non-null reference value
x
,x.equals(x)
should returntrue
. - It is symmetric: for any non-null reference values
x
andy
,x.equals(y)
should returntrue
if and only ify.equals(x)
returnstrue
. - It is transitive: for any non-null reference values
x
,y
, andz
, ifx.equals(y)
returnstrue
andy.equals(z)
returnstrue
, thenx.equals(z)
should returntrue
. - It is consistent: for any non-null reference values
x
andy
, multiple invocations ofx.equals(y)
consistently returntrue
or consistently returnfalse
, provided no information used inequals
comparisons on the objects is modified. - For any non-null reference value
x
,x.equals(null)
should returnfalse
.
An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.
Parameters | |
---|---|
obj |
Object : This value may be null . |
Returns | |
---|---|
boolean |
true if this object is the same as the obj
argument; false otherwise. |
getDescription
public String getDescription ()
Returns a user visible description of the accessory.
Returns | |
---|---|
String |
the accessory description, or null if not set |
getManufacturer
public String getManufacturer ()
Returns the manufacturer name of the accessory.
Returns | |
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String |
the accessory manufacturer
This value cannot be null . |
getModel
public String getModel ()
Returns the model name of the accessory.
Returns | |
---|---|
String |
the accessory model
This value cannot be null . |
getSerial
public String getSerial ()
Returns the unique serial number for the accessory. This is an optional serial number that can be used to differentiate between individual accessories of the same model and manufacturer
Returns | |
---|---|
String |
the unique serial number, or null if not set |
Throws | |
---|---|
SecurityException |
if the app targets SDK >= android.os.Build.VERSION_CODES.Q
and the app does not have permission to read from the accessory. |
getUri
public String getUri ()
Returns the URI for the accessory. This is an optional URI that might show information about the accessory or provide the option to download an application for the accessory
Returns | |
---|---|
String |
the accessory URI, or null if not set |
getVersion
public String getVersion ()
Returns the version of the accessory.
Returns | |
---|---|
String |
the accessory version, or null if not set |
hashCode
public int hashCode ()
Returns a hash code value for the object. This method is
supported for the benefit of hash tables such as those provided by
HashMap
.
The general contract of hashCode
is:
- Whenever it is invoked on the same object more than once during
an execution of a Java application, the
hashCode
method must consistently return the same integer, provided no information used inequals
comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. - If two objects are equal according to the
equals
method, then calling thehashCode
method on each of the two objects must produce the same integer result. - It is not required that if two objects are unequal
according to the
equals
method, then calling thehashCode
method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
Returns | |
---|---|
int |
a hash code value for this object. |
toString
public String toString ()
Returns a string representation of the object.
Returns | |
---|---|
String |
a string representation of the object. |
writeToParcel
public void writeToParcel (Parcel parcel, int flags)
Flatten this object in to a Parcel.
Parameters | |
---|---|
parcel |
Parcel : The Parcel in which the object should be written.
This value cannot be null . |
flags |
int : Additional flags about how the object should be written.
May be 0 or Parcelable.PARCELABLE_WRITE_RETURN_VALUE .
Value is either 0 or a combination of Parcelable.PARCELABLE_WRITE_RETURN_VALUE , and android.os.Parcelable.PARCELABLE_ELIDE_DUPLICATES |