android - 如何在扩展 BroadcastReceiver 的类中注册广播接收器？

Question

我看过所有有关注册 BroadcastReceiver 的示例，并且所有示例都在没有扩展 BroadcastReceiver 类的情况下注册了接收器。但是我有以下代码

package vertex2016.mvjce.edu.bluealert;

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.widget.ArrayAdapter;
import android.widget.ListView;

import java.util.UUID;

public class SearchBLDev extends BroadcastReceiver {

    private BluetoothAdapter BTAdapter = BluetoothAdapter.getDefaultAdapter();
    private ArrayAdapter BTArrayAdapter;
    private ListView BTListView;
    private BluetoothDevice BTD;
    public UUID myUUID;

    IntentFilter filter = new IntentFilter();

    public void discoveryStart()
    {
        filter.addAction(BluetoothDevice.ACTION_FOUND);
        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
        registerReceiver(SearchBLDev, filter) //PROBLEM OCCURS HERE        
    }

    @Override
    public void onReceive(Context context, Intent intent)
    {}
}

我可以使用 registerReceiver 方法注册一个 Receiver。它显示错误。

感谢您的宝贵时间。

Answer 1

您需要一个 Context 来调用 registerReceiver(this, filter)，因此您应该将其作为参数传递。

public void discoveryStart(Context context)
{
    filter.addAction(BluetoothDevice.ACTION_FOUND);
    filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
    filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
    context.registerReceiver(this, filter) //PROBLEM OCCURS HERE
}

然后你可以从你的Activity中调用它:

SearchBLDev broadcastReceiver = new SearchBLDev();
broadcastReceiver.discoveryStart(this);