【移動應(yīng)用開發(fā)技術(shù)】如何用HMSNearbyService給自己的App添加近距離數(shù)據(jù)傳輸功能

/upload/information/20200717/160/6610.gif/upload/information/20200717/160/6611.png2.1開發(fā)準(zhǔn)備2.2聲明系統(tǒng)權(quán)限<!--

Required

for

Nearby

Discovery

and

Nearby

Transfer

-->

<uses-permission

android:name="android.permission.BLUETOOTH"

/>

<uses-permission

android:name="android.permission.BLUETOOTH_ADMIN"

/>

<uses-permission

android:name="android.permission.ACCESS_WIFI_STATE"

/>

<uses-permission

android:name="android.permission.CHANGE_WIFI_STATE"

/>

<uses-permission

android:name="android.permission.ACCESS_COARSE_LOCATION"

/>

<uses-permission

android:name="android.permission.ACCESS_FINE_LOCATION"

/>

<!--

Required

for

FILE

payloads

-->

<uses-permission

android:name="android.permission.READ_EXTERNAL_STORAGE"/>

<uses-permission

android:name="android.permission.WRITE_EXTERNAL_STORAGE"

/>2.3選擇策略Policy

policy

=

Policy.POLICY_STAR;

BroadcastOption

broadcastOption

=

new

BroadcastOption.Builder().setPolicy

(policy).build();2.4廣播和掃描2.4.1

啟動廣播private

void

doStartBroadcasting()

{

Policy

policy

=

Policy.POLICY_STAR;

BroadcastOption

broadcastOption

=

new

BroadcastOption.Builder().setPolicy(policy).build();

Nearby.getDiscoveryEngine(getApplicationContext())

.startBroadcasting(name,

serviceId,

connectCallback,

broadcastOption)

.addOnSuccessListener(

new

OnSuccessListener<Void>()

{

@Override

public

void

onSuccess(Void

aVoid)

{

/*

We

are

broadcasting.

*/

}

})

.addOnFailureListener(

new

OnFailureListener()

{

@Override

public

void

onFailure(Exception

e)

{

/*

Fail

to

start

broadcasting.

*/

}

});

}2.4.2

啟動掃描private

void

doStartScan()

{

Policy

policy

=

Policy.POLICY_STAR;

ScanOption

scanOption

=

new

ScanOption.Builder().setPolicy(policy).build();

Nearby.getDiscoveryEngine(getApplicationContext())

.startScan(serviceId,

scanEndpointCallback,

scanOption)

.addOnSuccessListener(

new

OnSuccessListener<Void>()

{

@Override

public

void

onSuccess(Void

aVoid)

{

/*

Start

scan

success.

*/

}

})

.addOnFailureListener(

new

OnFailureListener()

{

@Override

public

void

onFailure(Exception

e)

{

/*

Fail

to

start

scan.

*/

}

});

}private

ScanEndpointCallback

scanEndpointCallback

=

new

ScanEndpointCallback()

{

@Override

public

void

onFound(String

endpointId,

ScanEndpointInfo

discoveryEndpointInfo)

{

mEndpointId

=

endpointId;

mDiscoveryEngine.requestConnect(myNameStr,

mEndpointId,

mConnCb);

}

@Override

public

void

onLost(String

endpointId)

{

Log.d(TAG,

"Nearby

Connection

Demo

app:

Lost

endpoint:

"

+

endpointId);

}

};2.4.3

停止廣播2.4.4

停止掃描2.5建立連接2.5.1

請求連接private

void

doStartConnect(String

name,

String

endpointId)

throws

RemoteException

{

Nearby.getDiscoveryEngine(getApplicationContext())

.requestConnect(name,

endpointId,

connectCallback)

.addOnSuccessListener(

new

OnSuccessListener<Void>()

{

@Override

public

void

onSuccess(Void

aVoid)

{

/*

Request

success.

*/

}

})

.addOnFailureListener(

new

OnFailureListener()

{

@Override

public

void

onFailure(Exception

e)

{

/*

Fail

to

request

connect.

*/

}

});

}2.5.2

確認(rèn)連接private

final

ConnectCallback

connectCallback

=

new

ConnectCallback()

{

@Override

public

void

onEstablish(String

endpointId,

ConnectInfo

connectInfo)

{

/*

Accept

the

connection

request

without

notifying

user.

*/

Nearby.getDiscoveryEngine(getApplicationContext())

.acceptConnect(endpointId,

dataCallback);

}

@Override

public

void

onResult(String

endpointId,

ConnectResult

result)

{

switch

(result.getStatus().getStatusCode())

{

case

StatusCode.STATUS_SUCCESS:

/*

The

connection

was

established

successfully,

we

can

exchange

data.

*/

break;

case

StatusCode.STATUS_CONNECT_REJECTED:

/*

The

Connection

was

rejected.

*/

break;

default:

/*

other

unknown

status

code.

*/

}

}

@Override

public

void

onDisconnected(String

endpointId)

{

/*

The

connection

was

disconneted.

*/

}

};2.5.3

驗(yàn)證連接@Override

public

void

onEstablish(String

endpointId,

ConnectInfo

connectInfo)

{

AlertDialog.Builder

builder

=

new

AlertDialog.Builder(getApplicationContext());

builder.setTitle(connectInfo.getEndpointName()

+

"

request

connection")

.setMessage("Please

confirm

the

match

code

is:

"

+

connectInfo.getAuthCode())

.setPositiveButton(

"Accept",

(DialogInterface

dialog,

int

which)

->

/*

Accept

the

connection.

*/

Nearby.getDiscoveryEngine(getApplicationContext())

.acceptConnect(endpointId,

dataCallback))

.setNegativeButton(

"Reject",

(DialogInterface

dialog,

int

which)

->

/*

Reject

the

connection.

*/

Nearby.getDiscoveryEngine(getApplicationContext())

.rejectConnect(endpointId))

.setIcon(android.R.drawable.ic_dialog_alert);

AlertDialog

alert

=

builder.create();

alert.show();

}2.6傳輸數(shù)據(jù)2.6.1數(shù)據(jù)類型static

class

BytesDataReceiver

extends

DataCallback

{

@Override

public

void

onReceived(String

endpointId,

Data

data)

{

/*

BYTES

data

is

sent

as

a

single

block,

so

we

can

get

complete

data.

*/

if

(data.getType()

==

Data.Type.BYTES)

{

byte[]

receivedBytes

=

data.asBytes();

}

}

@Override

public

void

onTransferUpdate(String

endpointId,

TransferStateUpdate

update)

{

/*

We

will

receive

TRANSFER_STATE_SUCCESS

update

after

onReceived()

called.

*/

}

}File

fileToSend

=

new

File(getApplicationContext().getFilesDir(),

"fileSample.txt");

try

{

Data

fileData

=

Data.fromFile(fileToSend);

Nearby.getTransferEngine(getApplicationContext())

.sendData(endpointList,

fileData);

}

catch

(FileNotFoundException

e)

{

/*

Exception

handle.

*/

}ParcelFileDescriptor

pfd

=

getContentResolver().openFileDescriptor(uri,

"r");

Data

fileData

=

Data.fromFile(pfd);/*

We

can

get

the

received

file

in

the

Download

folder.

*/

File

payloadFile

=

fileData.asFile().asJava