android搜索周边蓝牙并以listview展示

要搜索周围的蓝牙设备并在Android应用程序中以ListView的形式显示它们，您需要执行以下步骤：

1. 确保您的应用程序已获得所需的蓝牙权限。

2. 通过调用BluetoothAdapter.getDefaultAdapter()来获取蓝牙适配器实例。

3. 使用BluetoothAdapter实例启用蓝牙。

4. 实现一个BroadcastReceiver来处理搜索结果和状态更改。

5. 在列表视图中显示蓝牙设备。

下面是一个简单的代码示例：

public class MainActivity extends AppCompatActivity {
    private BluetoothAdapter bluetoothAdapter;
    private ArrayAdapter<String> deviceListAdapter;
    private List<String> deviceList = new ArrayList<String>();

    private BroadcastReceiver bluetoothReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            if (BluetoothAdapter.ACTION_STATE_CHANGED.equals(action)) {
                final int state = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE, BluetoothAdapter.ERROR);
                if (state == BluetoothAdapter.STATE_ON) {
                    Toast.makeText(getApplicationContext(), "Bluetooth is ON", Toast.LENGTH_SHORT).show();
                }
            } else if (BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)) {
                deviceList.clear();
                Toast.makeText(getApplicationContext(), "Discovering Bluetooth devices...", Toast.LENGTH_SHORT).show();
            } else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
                deviceListAdapter.notifyDataSetChanged();
                Toast.makeText(getApplicationContext(), "Discovery completed", Toast.LENGTH_SHORT).show();
            } else if (BluetoothDevice.ACTION_FOUND.equals(action)) {
                BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
                if (!deviceList.contains(device.getName() + "\n" + device.getAddress())) {
                    deviceList.add(device.getName() + "\n" + device.getAddress());
                }
            }
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ListView listView = findViewById(R.id.listView);
        deviceListAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, deviceList);
        listView.setAdapter(deviceListAdapter);

        bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        if (bluetoothAdapter == null) {
            Toast.makeText(getApplicationContext(), "Bluetooth not supported on this device", Toast.LENGTH_SHORT).show();
        } else {
            if (!bluetoothAdapter.isEnabled()) {
                Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
                startActivityForResult(enableBtIntent, 0);
            }
        }
    }

    @Override
    protected void onResume() {
        super.onResume();

        IntentFilter filter = new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED);
        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
        filter.addAction(BluetoothDevice.ACTION_FOUND);
        registerReceiver(bluetoothReceiver, filter);
    }

    @Override
    protected void onPause() {
        super.onPause();
        unregisterReceiver(bluetoothReceiver);
    }

    public void discoverDevices(View view) {
        if (bluetoothAdapter.isDiscovering()) {
            bluetoothAdapter.cancelDiscovery();
        }
        bluetoothAdapter.startDiscovery();
    }
}

在此示例中，我们在onCreate方法中设置ListView并获取BluetoothAdapter实例。我们还检查蓝牙是否可用，并在需要时请求用户启用它。

在onResume方法中，我们注册了BroadcastReceiver以接收蓝牙状态更改和搜索结果。discoverDevices方法处理开始搜索的点击事件。

在BroadcastReceiver中，我们处理各种操作，并更新设备列表。在发现设备时，我们检查该设备是否已添加到列表中，如果没有，则添加它。

最后，在onPause方法中，我们取消注册BroadcastReceiver以避免内存泄漏。