Passing Data from Broadcast Receiver to another Ac

问题:

Hi I've been having an issue with Broadcast Receivers and passing information to another activity. I'm trying to create an application that will capture incoming SMS messages, look for a website in the text, then pop up an Alert Dialog box asking if the user wants to go to the website.

public class TextReceiver extends BroadcastReceiver{

public void onReceive(Context context, Intent intent)
{
    // .. other code that
    // sets received SMS into message

    Toast toast = Toast.makeText(context,
            "Received Text: " + message.getMessageBody(), Toast.LENGTH_LONG);
            toast.show();
 }

So that code works fine, receive a text it pops up a toast with the message. The toast is useless but it shows the receiver works. But I want to communicate with an activity to show an Alert Dialog and start up a webView. I already programmed the code that will take a string search for the website and open the webView. Is it possible to get the string from the broadcast receiver and do something like this?:

    public class ReceiveText extends Activity{
public void onCreate(Bundle savedInstanceState) {

// Somehow pass the string from the receiver into this activity, 
//stored in variable messages

findOpen(messages);

// is that possible?

}
public class findOpen(string messages){
// do stuff ... open alert...open site if OK
}

So basically I just want to pass a string from a Broadcast Receiver to another activity that will use that string. The rest of the code is basically in place all I need is that string... I'm new to this and Java and any help would be much appreciated. Thanks

回答1:

If you have your activity named ReceiveText, then in your BroadcastReceiver, you should do the following:

Intent i = new Intent(context, ReceiveText.class);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
i.putExtra("message", message.getMessageBody());
context.startActivity(i);

Then, in your activity, you will need to getExtra as so:

Intent intent = getIntent();
String message = intent.getStringExtra("message");

And then you will use message as you need.

If you simply want the ReceiveText activity to show the message as a dialog, declare <activity android:theme="@android:style/Theme.Dialog" /> in your manifest for ReceiveText and then set the message to a textview in the activity.

Let me know if I need to add anything else.

回答2:

1. Instantiate a BroadcastReceiver in the activity you want to get your data to, for example:

   private BroadcastReceiver mServiceReceiver = new BroadcastReceiver(){
       @Override
       public void onReceive(Context context, Intent intent)
       {
           //Extract your data - better to use constants...
           String IncomingSms=intent.getStringExtra("incomingSms");//
           String phoneNumber=intent.getStringExtra("incomingPhoneNumber");
   
       }
   };
   

2. Unregister your receiver on onPause():

   @Override
   protected void onPause() {
       super.onPause();
       try {
           if(mServiceReceiver != null){
           unregisterReceiver(mServiceReceiver);
           }
       } catch (Exception e) {
          e.printStackTrace();
       }
   }
   

3. Register it on onResume():

   protected void onResume() {
       super.onResume();
       IntentFilter filter = new IntentFilter();
       filter.addAction("android.intent.action.SmsReceiver");
       registerReceiver(mServiceReceiver , filter);
   }
   

4. Broadcast your data from the service via an Intent, for Example:

   Intent i = new Intent("android.intent.action.SmsReceiver").putExtra("incomingSms", message);
   i.putExtra("incomingPhoneNumber", phoneNumber);
   context.sendBroadcast(i);
   

and that's it! goodLuck!