android - 如何在不使用 onCreate() 的情况下将数据从 BroadcastReceiver 传递到 Activity

Question

关于将数据从 BroadcastReceiver 传递到 Activity，我遇到了一个严重的问题。让我仔细看看我的问题。我有一个用于接收来电的类 PhoneStateReceiver extends BroadcastReceiver。

public class PhoneStateReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        try {
            System.out.println("Receiver start");
            String state = intent.getStringExtra(TelephonyManager.EXTRA_STATE);
            String incomingNumber = intent.getStringExtra(TelephonyManager.EXTRA_INCOMING_NUMBER);
            if(state.equals(TelephonyManager.EXTRA_STATE_RINGING)){

            }            
        }
        catch (Exception e){
            e.printStackTrace();
        }
    }
}

来电将被发送到一个名为ReceiverActivity 的Activity。 ReceiverActivity 接收来电并通过套接字连接将其发送到服务器。套接字连接在 onCreate 函数中初始化。我用谷歌搜索并找到了将数据从 BroadcastReceiver 传递到 Activity 的服务器方式。常见的方式是通过putExtra函数发送数据，调用startActivity。但是，该方法会再次调用onCreate，然后连接套接字，重新绘制UI。因此，这对我的情况没有帮助。

在我的目标中，如果手机收到来电，它将把来电发送到ReceiverActivity。 ReceiverActivity 接收消息并调用发送函数。哪种方法最好？谢谢

将数据从 BroadcastReceiver 传递到 ReceiverActivity 的常用方法如下所示

在 PhoneStateReceiver 类中:

Intent intent_phonenum = new Intent(context, ReceiverActivity.class);
intent_phonenum.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent_phonenum.putExtra("phone_num", incomingNumber);
context.startActivity(intent_phonenum);

在 ReceiverActivity 类中:

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        connect_socket();
        Intent intent = getIntent();
        phone_num = intent.getStringExtra("phone_num");
        send(phone_num);
}

Answer 1

简单，无需任何第三方库。

确保 BroadcastReceiver 必须在 OnPause() 上注册和注销。

你必须做两件事

在您的 Activity 中注册一个接收器，如下所示。

public class MainActivity extends Activity {

    Context context;
    BroadcastReceiver updateUIReciver;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        context = this;

        IntentFilter filter = new IntentFilter();
        filter.addAction("service.to.activity.transfer");
        updateUIReciver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                //UI update here
                if (intent != null)
                    Toast.makeText(context, intent.getStringExtra("number").toString(), Toast.LENGTH_LONG).show();
            }
        };
        registerReceiver(updateUIReciver, filter);
    }
}

现在为您服务

public class PhoneStateReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        try {
            System.out.println("Receiver start");
            String state = intent.getStringExtra(TelephonyManager.EXTRA_STATE);
            String incomingNumber = intent.getStringExtra(TelephonyManager.EXTRA_INCOMING_NUMBER);
            if (state.equals(TelephonyManager.EXTRA_STATE_RINGING)) {
                Intent local = new Intent();
                local.setAction("service.to.activity.transfer");
                local.putExtra("number", incomingNumber);
                context.sendBroadcast(local);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}