Bluetooth operations for Android Development

Bluetooth operations for Android Development
Bluetooth operation
1. What is Bluetooth?
1. A wireless communication protocol widely used by Bluetooth
2. Mainly for short-range communication (10 m)
3. It is often used in mobile communication devices such as headphones, mouse, and keyboard.
2. Bluetooth-related APIs
1. effecthadapter: represents a local Bluetooth device.
2. effecthdevice: represents a remote Bluetooth device.
3. settings required for Bluetooth
You must declare the Bluetooth operation permission in AndroidManifest.
<Uses-permission android: name = "android. permission. BLUETOOTH"/>
<Uses-permission android: name = "android. permission. effecth_admin"/>
4. Scan the paired bluetooth device
1. Obtain the thadapter object
Descrithadapter adapter = descrithadapter. getdefaadapter adapter ()
2. Determine whether the current device has a bluetooth device.
If (adapter! = Null ){}
3. Determine whether the bluetooth device on the current device is enabled.
Use the adapter. isEnabled () method
4. Get all paired Bluetooth devices
Set <effecthdevice> devices = adapter. getBondedDevices ();
5. Set the visibility of Bluetooth devices
1. Create an intent object:
Intent discoverableIntent = new Intent (effecthadapter. ACTION_REQUEST_DISCOVERABLE );
2. Set the visibility time. The maximum value is 300 s. If the value exceeds 300 s, the system will automatically set it to s.
DiscoverableIntent. putExtra (effecthadapter. EXTRA_DISCOVERABLE_DURATION, 300 );
3. Start the Android built-in activity and pass the Parameter
StartActivity (discoverableIntent );
6. Scan for visible Bluetooth
1. Call startDiscovery () to scan visible devices
Descrithadapter. getdefaadapter adapter (). startDiscovery ();
2. A broadcast is sent every time the system is scanned.
A. Create A filter to filter broadcast ACTION_FOUND.
IntentFilter intentFilter = new IntentFilter (effecthdevice. ACTION_FOUND );
B. Create a broadcast Receiver
Extends threceiver extends threceiver = new extends threceiver ();
C. register the receiver
RegisterReceiver (FIG, intentFilter );
D. retrieve data from broadcast
String action = intent. getAction ();
// Retrieve the remote Bluetooth device from the intent
Effecthdevice device = intent. getParcelableExtra (effecthdevice. EXTRA_DEVICE );
VII. Source Code
MainActivity. java

 
 

  
  
Package com. example. bluetooth;

  
  


  
  
Import java. util. Iterator;

  
  
Import java. util. Set;

  
  


  
  
Import android. OS. Bundle;

  
  
Import android. app. Activity;

  
  
Import android. app. SearchManager. OnCancelListener;

  
  
Import android. bluetooth. javasthadapter;

  
  
Import android. bluetooth. systthdevice;

  
  
Import android. content. BroadcastReceiver;

  
  
Import android. content. Context;

  
  
Import android. content. DialogInterface;

  
  
Import android. content. IntentFilter;

  
  
Import android. content. DialogInterface. OnClickListener;

  
  
Import android. content. Intent;

  
  
Import android. view. Menu;

  
  
Import android. view. View;

  
  
Import android. webkit. WebView. FindListener;

  
  
Import android. widget. Button;

  
  
Import android. widget. EditText;

  
  


  
  
Public class MainActivity extends Activity

  
  
{

  
  


  
  
Private Button findBtn = null;

  
  
Private Button scanBtn = null;

  
  
Private Button setBtn = null;

  
  
Private EditText edit1 = null;

  
  


  
  
@ Override

  
  
Protected void onCreate (Bundle savedInstanceState)

  
  
{

  
  
Super. onCreate (savedInstanceState );

  
  
SetContentView (R. layout. activity_main );

  
  
// Find the button

  
  
FindBtn = (Button) findViewById (R. id. findBtn );

  
  
ScanBtn = (Button) findViewById (R. id. scanBtn );

  
  
SetBtn = (Button) findViewById (R. id. setBtn );

  
  
// Set the listener

  
  
FindBtn. setOnClickListener (new btnOnclickListener ());

  
  
ScanBtn. setOnClickListener (new btnOnclickListener ());

  
  
SetBtn. setOnClickListener (new btnOnclickListener ());

  
  


  
  
Edit1 = (EditText) findViewById (R. id. edit1 );

  
  
// Create a filter to filter broadcast ACTION_FOUND

  
  
IntentFilter intentFilter = new IntentFilter (effecthdevice. ACTION_FOUND );

  
  
// Create a broadcast Receiver

  
  
Extends threceiver extends threceiver = new extends threceiver ();

  
  
// Register the receiver

  
  
RegisterReceiver (FIG, intentFilter );

  
  
}

  
  


  
  
Class btnOnclickListener implements android. view. View. OnClickListener

  
  
{

  
  


  
  
@ Override

  
  
Public void onClick (View v)

  
  
{

  
  
// TODO Auto-generated method stub

  
  
Switch (v. getId ())

  
  
{

  
  
Case R. id. findBtn:

  
  
// Obtain the thadapter object

  
  
Descrithadapter adapter = descrithadapter. getdefaadapter adapter ();

  
  
// If the device is obtained

  
  
If (adapter! = Null)

  
  
{

  
  
// Update edittext and print the device

  
  
Edit1.append ("have! "+ '\ N ');

  
  
// If the device is not enabled

  
  
If (! Adapter. isEnabled ())

  
  
{

  
  
// Start a new activity and enable Bluetooth

  
  
Intent intent = new Intent (effecthadapter. ACTION_REQUEST_ENABLE );

  
  
StartActivity (intent );

  
  
}

  
  
// Obtain all paired Bluetooth devices to obtain a bluetooth device set

  
  
Set <effecthdevice> devices = adapter. getBondedDevices ();

  
  
If (devices. size ()> 0)

  
  
{

  
  
// If there is a pair of Bluetooth, print them one by one using Iteration

  
  
For (Iterator iterator = devices. iterator (); iterator. hasNext ();)

  
  
{

  
  
Effecthdevice = (effecthdevice) iterator. next ();

  
  
Edit1.append (effecthdevice. getAddress () + '\ n ');

  
  
}

  
  
}

  
  
}

  
  
Else

  
  
{

  
  
Edit1.append ("no device !! ");

  
  
}

  
  
Break;

  
  
Case R. id. scanBtn:

  
  
// Call startDiscovery () to scan visible devices

  
  
Descrithadapter. getdefaadapter adapter (). startDiscovery ();

  
  
Break;

  
  
Case R. id. setBtn:

  
  
// Create intent and pass parameters through intent

  
  
Intent discoverableIntent = new Intent (effecthadapter. ACTION_REQUEST_DISCOVERABLE );

  
  
// Set the duration of the visible State. If the duration exceeds 300 s, the system will automatically set it to 300 s.

  
  
DiscoverableIntent. putExtra (effecthadapter. EXTRA_DISCOVERABLE_DURATION, 300 );

  
  
// Start the activity, which comes with Android

  
  
StartActivity (discoverableIntent );

  
  
Break;

  
  
Default:

  
  
Break;

  
  
}

  
  


  
  
}

  
  
}

  
  


  
  
Private class extends threceiver extends BroadcastReceiver

  
  
{

  
  


  
  
@ Override

  
  
Public void onReceive (Context context, Intent intent)

  
  
{

  
  
// TODO Auto-generated method stub

  
  
// Accept intent

  
  
String action = intent. getAction ();

  
  
// Retrieve the remote Bluetooth device from the intent

  
  
Effecthdevice device = intent. getParcelableExtra (effecthdevice. EXTRA_DEVICE );

  
  
Edit1.append ("find new device:" + device. getAddress () + "\ n ");

  
  
}

  
  


  
  
}

  
  
@ Override

  
  
Public boolean onCreateOptionsMenu (Menu menu)

  
  
{

  
  
// Inflate the menu; this adds items to the action bar if it is present.

  
  
GetMenuInflater (). inflate (R. menu. main, menu );

  
  
Return true;

  
  
}

  
  


  
  
}
 
 

Layout File

 
 

  
  
<RelativeLayout xmlns: android = "http://schemas.android.com/apk/res/android"

  
  
Xmlns: tools = "http://schemas.android.com/tools"

  
  
Android: layout_width = "match_parent"

  
  
Android: layout_height = "match_parent"

  
  
Android: paddingBottom = "@ dimen/activity_vertical_margin"

  
  
Android: paddingLeft = "@ dimen/activity_horizontal_margin"

  
  
Android: paddingRight = "@ dimen/activity_horizontal_margin"

  
  
Android: paddingTop = "@ dimen/activity_vertical_margin"

  
  
Tools: context = ". MainActivity">

  
  


  
  
<Button

  
  
Android: id = "@ + id/findBtn"

  
  
Android: layout_width = "fill_parent"

  
  
Android: layout_height = "wrap_content"

  
  
Android: text = "scanning connected Bluetooth"

  
  
/>

  
  
<Button

  
  
Android: id = "@ + id/setBtn"

  
  
Android: layout_width = "fill_parent"

  
  
Android: layout_height = "wrap_content"

  
  
Android: layout_below = "@ + id/findBtn"

  
  
Android: text = "setting Bluetooth visibility"

  
  
/>

  
  
<Button

  
  
Android: id = "@ + id/scanBtn"

  
  
Android: layout_width = "fill_parent"

  
  
Android: layout_height = "wrap_content"

  
  
Android: layout_below = "@ + id/setBtn"

  
  
Android: text = "scanning Bluetooth visible around"

  
  
/>

  
  
<EditText

  
  
Android: id = "@ + id/edit1"

  
  
Android: layout_width = "fill_parent"

  
  
Android: layout_height = "wrap_content"

  
  
Android: layout_below = "@ + id/scanBtn"

  
  
/>

  
  


  
  
</RelativeLayout>