Question

我正在做蓝牙here的基本教程。

到目前为止，我的代码是

import java.util.Set;

import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.BroadcastReceiver;
import android.content.IntentFilter;
import android.os.Bundle;
import android.view.Menu;
import android.widget.ArrayAdapter;

public class MainActivityBlueTooth extends Activity {

    //private static final int REQUEST_ENABLE_BT = 0;
    ArrayAdapter<String> mArrayAdapter ;    


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

        BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        if (mBluetoothAdapter == null) {
            // Device does not support Bluetooth
        }


        /*if (!mBluetoothAdapter.isEnabled()) {
            Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
        }*/

        Set<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
                mArrayAdapter.add(device.getName() + "\n" + device.getAddress());
            }
        }

    }



    // Create a BroadcastReceiver for ACTION_FOUND
    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            // When discovery finds a device
            if (BluetoothDevice.ACTION_FOUND.equals(action)) {
                // Get the BluetoothDevice object from the Intent
                BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
                // Add the name and address to an array adapter to show in a ListView
                mArrayAdapter.add(device.getName() + "\n" + device.getAddress());
            }
        }
    };



    // Register the BroadcastReceiver
    IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
    registerReceiver(mReceiver, filter); // Don't forget to unregister during onDestroy


}

Eclipse在registerReceiver中为我提供了缺少方法的返回类型错误。你能告诉我一些我在这里做错了什么吗？我应该在onResume方法中注册我的接收器吗？很抱歉问一些如此微不足道的事情，但我找不到答案就是StackOverflow。

我也看了here和here没有运气。

Answer 1

它给你错误，因为你已经在方法之外定义了它。你的代码

IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
registerReceiver(mReceiver, filter); // Don't forget to unregister during onDestroy

不在任何方法内，只需创建一个如下所示的onResume（）方法并在其中移动代码。

@Override 
public void onResume()
{
    super.onResume();
    // Register the BroadcastReceiver
    IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
    registerReceiver(mReceiver, filter); // Don't forget to unregister during onDestroy
}

registerReceiver中缺少该方法的返回类型

1 个答案: