将数据从BroadcastReceiver类传递到Android Activity

Question

我正在开发一个Android应用程序,它具有一个功能,当应用程序运行时,如果我收到一条新的SMS消息,则需要使用TextToSpeech读取该消息的内容.我知道如何使用TextToSpeech阅读文本.我在我的应用程序上写了两个类.一个是MainActivity从Activity扩展而另一个是SmsReceiver从BroadcastReceiver扩展.当MainActivity运行时收到Sms我希望使用SmsReceiver获取sms消息的内容并将其传递给MainActivity,然后使用TextToSpeech在MainActivity中读取它.如何将sms的内容从SmsReceiver传递给我的MainActivity.我的SmsReceiver类的副本粘贴在下面.

public class SmsReceiver extends BroadcastReceiver{


@Override
public void onReceive(Context context, Intent intent) {
    //this stops notifications to others
    this.abortBroadcast();

    //---get the SMS message passed in---
    Bundle bundle = intent.getExtras();   
    SmsMessage[] msgs = null;
    String from = null;
    String msg= null;
    String str = "";            
    if (bundle != null)
    {
        //---retrieve the SMS message received---
        Object[] pdus = (Object[]) bundle.get("pdus");
        msgs = new SmsMessage[pdus.length];            
        for (int i=0; i<msgs.length; i++){
            msgs[i] = SmsMessage.createFromPdu((byte[])pdus[i]);                
            str += "SMS from " + msgs[i].getOriginatingAddress();
            from = msgs[i].getOriginatingAddress();
            str += " :";
            str += msgs[i].getMessageBody().toString();
            msg = msgs[i].getMessageBody().toString();
            str += "\n"; 
        }
        System.out.println("from "+from);
        System.out.println("msg "+msg);
        Toast.makeText(context, "SMS Received : ",Toast.LENGTH_LONG).show();

        //continue the normal process of sms and will get alert and reaches inbox
            this.clearAbortBroadcast();
        }
}

}

Answer 1

使用界面是一个适合我的解决方案.

在你的BroadcastReceiver中放入以下内容

public interface OnSmsReceivedListener {
    public void onSmsReceived(String sender, String message);
}

然后添加监听器

private OnSmsReceivedListener listener = null;

然后向BroadcastReceiver添加一个方法..

public void setOnSmsReceivedListener(Context context) {
    this.listener = (OnSmsReceivedListener) context;
}

然后在你的onReceive方法中,你可以做这样的事......

if (listener != null) {
    listener.onSmsReceived(sender, msg);
}

在通过实现OnSmsReceivedListener接口创建并注册BroadcastReceiver的活动中,然后执行以下操作

public class SomeActivity extends Activity implements OnSmsReceivedListener.....

private MissedCallActivity receiver;

在onCreate方法中添加

receiver = new MissedCallActivity();
receiver.setOnSmsListener(this);

然后覆盖接口使用的方法.

@Override
public void onSmsReceived(String sender, String message) {
    //Insert your text to speech code here
}

这应该够了吧.

另外,不要忘记在onResume()方法中注册接收器并在onPause()方法中注销它.另外,看看"from"如何以蓝色突出显示？这意味着它是Java语法的一部分,不能用作变量.

Answer 2

您可以使用意图传递数据。

在您的 BroadcastReceiver 中，创建一个 Intent：

Intent i = new Intent(getApplicationContext(), MainActivity.class);
i.putExtra("msgContent", msg);
i.putExtra("sender",from);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); // adding this flag starts the new Activity in a new Task 
startActivity(i);

然后在另一个活动中，您可以获得这些值，例如：

Bundle extras = getIntent().getExtras();
if (extras != null) {
    String messageContent = extras.getString("msgContent");
    String messageSender = extras.getString("sender");
}