I am developing an application for a Bluetooth client side, and inside this application has a listview that will list out all the connected devices. First, the application will check for the availability of the Bluetooth and then try to connect to another device(Server) , beside that, I initialised the intent filter in the manifest file.
Below is my code :
public class MainActivity extends AppCompatActivity {
ArrayAdapter<String> listAdapter;
ListView listView;
BluetoothAdapter mBluetoothAdapter;
Set<BluetoothDevice> bondedDevices;
private BluetoothSocket socket;
Intent discoverableIntent;
private BluetoothDevice remoteDevice;
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
if(intent.getAction().equalsIgnoreCase("android.bluetooth.BluetoothDevice.ACTION_ACL_CONNECTED"))
{
Log.i("Connect", "Connecting.>>>>");
unregisterReceiver(this);
remoteDevice = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
String Temp1 = remoteDevice.getName();
String Temp2 = remoteDevice.getAddress();
listAdapter.add(Temp1 + Temp2);
listView.setAdapter(listAdapter);
new Thread(reader).start();
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
IntentFilter intentFilter = new IntentFilter("com.example.jackpowell.bluetoothclient.ACTION_ACL_CONNECTED");
registerReceiver(mReceiver,intentFilter);
startDiscovery();
}
private void startDiscovery() {
mBluetoothAdapter.cancelDiscovery();
mBluetoothAdapter.startDiscovery();
}
public void init() {
listView = (ListView)findViewById(R.id.listView);
listAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,0);
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter == null) {
Toast.makeText(MainActivity.this, "Bluetooth is not supported in this device", Toast.LENGTH_SHORT).show();
finish();
} else {
if (!mBluetoothAdapter.isEnabled()) {
turnOnBluetooth();
}
}
bondedDevices = mBluetoothAdapter.getBondedDevices();
discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
startActivity(discoverableIntent);
}
private Runnable reader = new Runnable() {
@Override
public void run() {
try {
Log.i("Connect","Connecting...........");
android.util.Log.e("TrackingFlow", "Found: " + remoteDevice.getName());
UUID uuid = UUID.fromString("a60f35f0-b93a-11de-8a19-03002011c456");
socket = remoteDevice.createRfcommSocketToServiceRecord(uuid);
socket.connect();
} catch (Exception e) {
e.printStackTrace();
}
}
};
private void turnOnBluetooth() {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, 1);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_CANCELED) {
Toast.makeText(getApplicationContext(), "Bluetooth must be enabled to continue", Toast.LENGTH_SHORT).show();
finish();
}
}
@Override
protected void onDestroy() {
super.onDestroy();
unregisterReceiver(mReceiver);
}
}
my manifest:
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<receiver android:name="bluetoothclient">
<intent-filter>
<action android:name="android.bluetooth.BluetoothDevice.ACTION_ACL_CONNECTED" />
</intent-filter>
</receiver>
The problem now is onReceive() and registerReceiver() these method never been called, or maybe it already called, I just dont get it. If these method were called, the log cat should be displaying the log command. Why are these method never been called? thank you in advance!
The action name is "android.bluetooth.device.action.ACL_CONNECTED" (to use in manifest) or BluetoothDevice.ACTION_ACL_CONNECTED (to use in code, for intent filter). Action names in your code seem wrong.
Note, to register receiver in manifest the receiver name should be public class based on BroadcastReceiver, not sure what is the "bluetoothclient" meaning in the code above (you didn't show the receiver code).
Usually you don't need both manifest receiver and intent filter receiver in activity, one may be sufficient. The main difference is that manifest receiver can be independent from activity life cycle and receive even when activity is not running.
Try to listen also for ACTION_FOUND (per documentation after startDiscovery you'll receive BluetoothDevice.ACTION_FOUND) and others and try to reduce into minimal example. You need also check result of startDiscovery() which can return false on failure.
Here is slightly modified sample from Discovering devices section:
@Override
protected void onCreate(Bundle savedInstanceState) {
...
// Register for broadcasts
IntentFilter filter = new IntentFilter();
filter.addAction(BluetoothDevice.ACTION_FOUND);
filter.addAction(BluetoothDevice.ACTION_ACL_CONNECTED);
filter.addAction(BluetoothDevice.ACTION_ACL_DISCONNECTED);
filter.addAction(BluetoothDevice.ACTION_ACL_DISCONNECT_REQUESTED);
registerReceiver(mReceiver, filter);
...
if(!mBluetoothAdapter.startDiscovery()){
Log.e("Bluetooth", "discovery error");
}
}
// Create a BroadcastReceiver for bluetooth actions
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
Log.i("Bluetooth", "got action " + action);
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
// Discovery has found a device. Get the BluetoothDevice
// object and its info from the Intent.
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
String deviceName = device.getName();
String deviceHardwareAddress = device.getAddress(); // MAC address
Log.i("Bluetooth", "got device " + deviceName );
}
}
};
@Override
protected void onDestroy() {
super.onDestroy();
...
// Don't forget to unregister the ACTION_FOUND receiver.
unregisterReceiver(mReceiver);
}
Also note, per this question/answer, on some devices discovery does not always work as expected and there is a need for workarounds.
By the way, did you check the logcat for other errors, for example denied permissions etc.? You may try to enable location and add location permission.
Here is a working sample to display all devices:
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.testbluetooth"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="17"
android:targetSdkVersion="21" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
MainActivity.java
package com.example.testbluetooth;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.util.Log;
import android.view.ViewGroup.LayoutParams;
import android.widget.FrameLayout;
import android.widget.TextView;
public class MainActivity extends Activity {
TextView textView;
StringBuilder text = new StringBuilder();
private void addLine(String line)
{
Log.i(getClass().getSimpleName(), line);
text.append("[bluetooth] ").append(line).append('\n');
if(textView!=null)
textView.setText(text);
}
BluetoothAdapter mBluetoothAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.activity_main);
FrameLayout content = new FrameLayout(this);
textView = new TextView(this);
content.addView(textView, new FrameLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
addLine("onCreate");
setContentView(content);
// Register for broadcasts
IntentFilter filter = new IntentFilter();
filter.addAction(BluetoothDevice.ACTION_FOUND);
filter.addAction(BluetoothDevice.ACTION_ACL_CONNECTED);
filter.addAction(BluetoothDevice.ACTION_ACL_DISCONNECTED);
filter.addAction(BluetoothDevice.ACTION_ACL_DISCONNECT_REQUESTED);
registerReceiver(mReceiver, filter);
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
for(BluetoothDevice pairedDevice : mBluetoothAdapter.getBondedDevices())
{
addLine("got paired device " + pairedDevice.getName());
}
if(!mBluetoothAdapter.startDiscovery()){
addLine("ERROR: discovery error");
}
else
{
addLine("starting discovery");
}
}
// Create a BroadcastReceiver for bluetooth actions
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
addLine("got action " + action);
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
// Discovery has found a device. Get the BluetoothDevice
// object and its info from the Intent.
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
String deviceName = device.getName();
//String deviceHardwareAddress = device.getAddress(); // MAC address
addLine("got device " + deviceName );
}
}
};
}
