Question

I’m trying to create an image button that, when pressed, presents the users a list of Paired Bluetooth devices to connect to.

However, I get “Set cannot be resolved as a variable” at point ##1,
and “mArrayAdapber cannot be resolved” at point ##2
(##1 and ##2 are not part of the code…)

I used the code from the Android site, but being in the dark, I find myself in the dark.

I’d appreciate some guidance…

//Search

ImageButton bSearch = (ImageButton) findViewById(R.id.Search);
bSearch.setOnClickListener(new View.OnClickListener() {
    public void onClick(View view) {                        
        ##1Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
        // If there are paired devices
        if (pairedDevices.size() > 0) {
            // Loop through paired devices
            for (BluetoothDevice device : pairedDevices) {
                // Add the name and address to an array adapter to show in a ListView
                ##2mArrayAdapter.add(device.getName() + "\n" + device.getAddress());
            }
        }                                                                           
    }                       
});

Answer 1

For 1) Well if you haven’t done so , add

> import java.util.Set;

in your import statements . This will resolve “Set” error.

For 2) Declare and initialize

mArrayAdapter

For example in your Activity do :

private ArrayAdapter<String> mArrayAdapter;

and then on onCreate:

 mArrayAdapter= new ArrayAdapter<String>(this, <your layout file>);

which should then be added to a ListView

// Find and set up the ListView for newly discovered devices

   ListView newDevicesListView = (ListView)
 findViewById(R.id.<layout_file>);
         newDevicesListView.setAdapter(mArrayAdapter);

 newDevicesListView.setOnItemClickListener(mDeviceClickListener);

---

Refer to Bluetooth Chat example from Android examples. It should help you get going with the Bluetooth api’s

---

Update on comment :

If you look closely on BluetoothChat.java file in BT example, you’ll see this

public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if(D) Log.d(TAG, "onActivityResult " + resultCode);
        switch (requestCode) {
        case REQUEST_CONNECT_DEVICE:
            // When DeviceListActivity returns with a device to connect
            if (resultCode == Activity.RESULT_OK) {
                // Get the device MAC address
                String address = data.getExtras()
                                     .getString(DeviceListActivity.EXTRA_DEVICE_ADDRESS);
                // Get the BLuetoothDevice object
                BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
                // Attempt to connect to the device
                mChatService.connect(device);
            }
            break;
        case REQUEST_ENABLE_BT:
            // When the request to enable Bluetooth returns
            if (resultCode == Activity.RESULT_OK) {
                // Bluetooth is now enabled, so set up a chat session
                setupChat();
            } else {
                // User did not enable Bluetooth or an error occured
                Log.d(TAG, "BT not enabled");
                Toast.makeText(this, R.string.bt_not_enabled_leaving, Toast.LENGTH_SHORT).show();
                finish();
            }
        }
    }

Watch this line :

 // Attempt to connect to the device
 mChatService.connect(device);

This function connects to bluetooth device. First time it’ll ask you to pair it automatically. Once paired, next time it’ll auto connect to the bluetooth device.