startLeScan和stopLeScan在API级别24中折旧？如何扫描BLE设备？

时间：2017-07-13 08:05:44

标签： bluetooth bluetooth-lowenergy

我正在开发一个项目，其中BLE设备（RN-4871 - 蓝牙4.2低能耗模块）连接到目标板。 RN-4871设备可见并连接到从Play商店下载的 BLE扫描仪应用程序。 我正在使用从https://developer.android.com/samples/BluetoothLeGatt/project.html下载的代码段。 我刚刚将项目配置为Android Marshmallow（API＆gt; 21）并使用了上面下载的代码。 我正在使用moto c plus（牛轧糖）。

private LeDeviceListAdapter mLeDeviceListAdapter;
private BluetoothAdapter mBluetoothAdapter;
private void scanLeDevice(final boolean enable) {

    if (enable) {
        // Stops scanning after a pre-defined scan period.
        mHandler.postDelayed(new Runnable() {
            @Override
            public void run() {
                mScanning = false;
                mBluetoothAdapter.stopLeScan(mLeScanCallback);
                invalidateOptionsMenu();
            }
        }, SCAN_PERIOD);
        mScanning = true;
        mBluetoothAdapter.startLeScan(mLeScanCallback);
    } else {
        mScanning = false;
        mBluetoothAdapter.stopLeScan(mLeScanCallback);
    }
    invalidateOptionsMenu();
}

但它显示startLeScan和stopLeScan已折旧。所以我无法扫描可用的设备。

此外，我刚刚使用以下代码段将精确设备与UUID连接。

public static final ParcelUuid MY_UUID = 
ParcelUuid.fromString("00002A05-0000-1000-8000-00805F9B34FB");

 private void scanLeDevice(final boolean enable) {
    if(enable){
        ScanFilter aFilter = new ScanFilter.Builder()
                .setServiceUuid(BluetoothLeService.MY_UUID).build();

        ArrayList<ScanFilter> filters = new ArrayList<>();
        filters.add(aFilter);

        ScanSettings settings = new ScanSettings.Builder()
                .setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
                .build();
        mBluetoothLeScanner.startScan(filters, settings, (ScanCallback) mLeScanCallback);
    }
}

关闭应用程序。

DeviceScanActivity.java 

 import android.app.Activity;
 import android.app.ListActivity;
 import android.bluetooth.BluetoothAdapter;
 import android.bluetooth.BluetoothDevice;
 import android.bluetooth.BluetoothManager;
 import android.bluetooth.le.BluetoothLeScanner;
 import android.bluetooth.le.ScanCallback;
 import android.bluetooth.le.ScanFilter;
 import android.bluetooth.le.ScanSettings;
 import android.content.Context;
 import android.content.Intent;
 import android.content.pm.PackageManager;
 import android.os.Bundle;
 import android.os.Handler;
 import android.view.LayoutInflater;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.BaseAdapter;
 import android.widget.ListView;
 import android.widget.TextView;
 import android.widget.Toast;

 import java.util.ArrayList;
 public class DeviceScanActivity extends ListActivity {
 private LeDeviceListAdapter mLeDeviceListAdapter;
 private BluetoothAdapter mBluetoothAdapter;
 private BluetoothLeScanner mBluetoothLeScanner;

private boolean mScanning;
private Handler mHandler;

private static final int REQUEST_ENABLE_BT = 1;
// Stops scanning after 10 seconds.
private static final long SCAN_PERIOD = 10000;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    getActionBar().setTitle(R.string.title_devices);
    mHandler = new Handler();

    // Use this check to determine whether BLE is supported on the device.  Then you can
    // selectively disable BLE-related features.
    if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
        Toast.makeText(this, R.string.ble_not_supported, Toast.LENGTH_SHORT).show();
        finish();
    }

    // Initializes a Bluetooth adapter.  For API level 18 and above, get a reference to
    // BluetoothAdapter through BluetoothManager.
    final BluetoothManager bluetoothManager =
            (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
    mBluetoothAdapter = bluetoothManager.getAdapter();

    // Checks if Bluetooth is supported on the device.
    if (mBluetoothAdapter == null) {
        Toast.makeText(this, R.string.error_bluetooth_not_supported, Toast.LENGTH_SHORT).show();
        finish();
        return;
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.main, menu);
    if (!mScanning) {
        menu.findItem(R.id.menu_stop).setVisible(false);
        menu.findItem(R.id.menu_scan).setVisible(true);
        menu.findItem(R.id.menu_refresh).setActionView(null);
    } else {
        menu.findItem(R.id.menu_stop).setVisible(true);
        menu.findItem(R.id.menu_scan).setVisible(false);
        menu.findItem(R.id.menu_refresh).setActionView(
                R.layout.actionbar_indeterminate_progress);
    }
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.menu_scan:
            mLeDeviceListAdapter.clear();
            scanLeDevice(true);
            break;
        case R.id.menu_stop:
            scanLeDevice(false);
            break;
    }
    return true;
}

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

    // Ensures Bluetooth is enabled on the device.  If Bluetooth is not currently enabled,
    // fire an intent to display a dialog asking the user to grant permission to enable it.
    if (!mBluetoothAdapter.isEnabled()) {
        if (!mBluetoothAdapter.isEnabled()) {
            Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
        }
    }

    // Initializes list view adapter.
    mLeDeviceListAdapter = new LeDeviceListAdapter();
    setListAdapter(mLeDeviceListAdapter);
    scanLeDevice(true);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    // User chose not to enable Bluetooth.
    if (requestCode == REQUEST_ENABLE_BT && resultCode == Activity.RESULT_CANCELED) {
        finish();
        return;
    }
    super.onActivityResult(requestCode, resultCode, data);
}

@Override
protected void onPause() {
    super.onPause();
    scanLeDevice(false);
    mLeDeviceListAdapter.clear();
}

@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
    final BluetoothDevice device = mLeDeviceListAdapter.getDevice(position);
    if (device == null) return;
    final Intent intent = new Intent(this, DeviceControlActivity.class);
    intent.putExtra(DeviceControlActivity.EXTRAS_DEVICE_NAME, device.getName());
    intent.putExtra(DeviceControlActivity.EXTRAS_DEVICE_ADDRESS, device.getAddress());
    if (mScanning) {
        mBluetoothAdapter.stopLeScan(mLeScanCallback);
        mScanning = false;
    }
    startActivity(intent);
}


private void scanLeDevice(final boolean enable) {
    if (enable) {
        // Stops scanning after a pre-defined scan period.
        mHandler.postDelayed(new Runnable() {
            @Override
            public void run() {
                mScanning = false;
                mBluetoothAdapter.stopLeScan(mLeScanCallback);
                invalidateOptionsMenu();
            }
        }, SCAN_PERIOD);

        mScanning = true;
        mBluetoothAdapter.startLeScan(mLeScanCallback);
    } else {
        mScanning = false;
        mBluetoothAdapter.stopLeScan(mLeScanCallback);
    }
    invalidateOptionsMenu();
}


// Adapter for holding devices found through scanning.
private class LeDeviceListAdapter extends BaseAdapter {
    private ArrayList<BluetoothDevice> mLeDevices;
    private LayoutInflater mInflator;

    public LeDeviceListAdapter() {
        super();
        mLeDevices = new ArrayList<BluetoothDevice>();
        mInflator = DeviceScanActivity.this.getLayoutInflater();
    }

    public void addDevice(BluetoothDevice device) {
        if(!mLeDevices.contains(device)) {
            mLeDevices.add(device);
        }
    }

    public BluetoothDevice getDevice(int position) {
        return mLeDevices.get(position);
    }

    public void clear() {
        mLeDevices.clear();
    }

    @Override
    public int getCount() {
        return mLeDevices.size();
    }

    @Override
    public Object getItem(int i) {
        return mLeDevices.get(i);
    }

    @Override
    public long getItemId(int i) {
        return i;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {
        ViewHolder viewHolder;
        // General ListView optimization code.
        if (view == null) {
            view = mInflator.inflate(R.layout.listitem_device, null);
            viewHolder = new ViewHolder();
            viewHolder.deviceAddress = (TextView) view.findViewById(R.id.device_address);
            viewHolder.deviceName = (TextView) view.findViewById(R.id.device_name);
            view.setTag(viewHolder);
        } else {
            viewHolder = (ViewHolder) view.getTag();
        }

        BluetoothDevice device = mLeDevices.get(i);
        final String deviceName = device.getName();
        if (deviceName != null && deviceName.length() > 0)
            viewHolder.deviceName.setText(deviceName);
        else
            viewHolder.deviceName.setText(R.string.unknown_device);
        viewHolder.deviceAddress.setText(device.getAddress());

        return view;
    }
}

// Device scan callback.
private BluetoothAdapter.LeScanCallback mLeScanCallback =
        new BluetoothAdapter.LeScanCallback() {

    @Override
    public void onLeScan(final BluetoothDevice device, int rssi, byte[] scanRecord) {
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                mLeDeviceListAdapter.addDevice(device);
                mLeDeviceListAdapter.notifyDataSetChanged();
            }
        });
    }
};

static class ViewHolder {
    TextView deviceName;
    TextView deviceAddress;
}

}

如何连接RN-4871 ??

1 个答案:

答案 0 :(得分：0)

代码示例使您的问题变得混乱。 在最后显示的代码示例中，您已经有一个字段mBluetoothLeScanner，  但是你没有使用它。

只是做：

// Initializes a Bluetooth adapter.  For API level 18 and above, get a  reference to
// BluetoothAdapter through BluetoothManager.
final BluetoothManager bluetoothManager =
(BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
 mBluetoothAdapter = bluetoothManager.getAdapter();
 mBluetoothLeScanner =  mBluetoothAdapter.BluetoothLeScanner;

并在其余代码中替换

mBluetoothAdapter.stopLeScan(mLeScanCallback) 和  mBluetoothAdapter.startLeScan(mLeScanCallback) 与

mBluetoothLeScanner.stopScan( mLeScanCallback) 和

mBluetoothLeScanner.startScan( mLeScanCallback)

相关问题
最新问题