Passing parameters between service and activity

Question

Code for passing float value from service to activity:

call.putExtra("floatvalue", fv);
call.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(call);

Code for getting float value in the activity:

Bundle extras=new Bundle();
float value = extras.getFloat("floatvalue");

The problem is no matter what is passed as the float value from the service, I get only 0.0 in the activity.

What is the problem with the code?

EDIT

I changed the code in the activity to

Bundle extras=new Bundle();
extras=getIntent().getExtras();
float value = extras.getFloat("floatvalue");

It didnt work.

have u added `extras = getIntent().getExtras();` before getting value from bundle ? — ρяσѕρєя K, Jan 14 '13 at 13:14
As ρяσѕρєя K mentioned, you should get your extras from intent in onStartCommand, not construct the new one. — Yaroslav Mytkalyk, Jan 14 '13 at 13:16
@ρяσѕρєяK - I tried it now, doesn't seem to be working. It's still 0. — Karthik Balakrishnan, Jan 14 '13 at 13:20
@Torcellite : first make sure you are trying this code in onCreate method and if u are getting still null then also try as `float value=getIntent().getFloatExtra("floatvalue",0);` — ρяσѕρєя K, Jan 14 '13 at 13:27
@ρяσѕρєяK Yeah, it's in the onCreate method of the activity. "getFloatExtra()" requires two parameters, the string value and a default float value. If I set the float value, to 0 or 1, then "value" becomes only 0 or 1. Not what was passed. — Karthik Balakrishnan, Jan 14 '13 at 13:29

N Jay · Accepted Answer · 2013-01-14T15:25:46.613

1

Try this:

float value =  getIntent().getFloatExtra("floatvalue", 0.0f);

Since you added the float to your intent before starting it, you should get the float from that intent not from the bundle.

edited Jan 14 '13 at 15:25

answered Jan 14 '13 at 13:17

N Jay

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In a service it is better to get intent.getFloat from onStartCommand, since onStartCommand can be called several times, but onCreate only once a lifecycle. – Yaroslav Mytkalyk Jan 14 '13 at 13:18
Can you please explain why this is answering OP's question? This answer was flagged due to length. – Jonas G. Drange Jan 14 '13 at 13:38
@JonasG.Drange can u please clarify what you just said? – N Jay Jan 14 '13 at 13:40
Nader, please expand your answer with a short explanation as to why this piece of code would solve the problem. See http://stackoverflow.com/questions/how-to-answer – Jonas G. Drange Jan 14 '13 at 13:43
@NaderAyyad I got this error `The method getFloat(String) is undefined for the type Intent` – Karthik Balakrishnan Jan 14 '13 at 14:24
@NaderAyyad `getIntent()` only has `getFloatExtra(String string, float defaultValue)` when I pass the parameters as `getFloatExtra("floatvalue", 0);` I get the value set to only 0. – Karthik Balakrishnan Jan 14 '13 at 14:39

score 1 · Answer 2 · edited May 23 '17 at 12:12

Define a listener in your service like this:

// listener ----------------------------------------------------
static ArrayList<OnNewLocationListener> arrOnNewLocationListener =
        new ArrayList<OnNewLocationListener>();

// Allows the user to set a OnNewLocationListener outside of this class and
// react to the event.
// A sample is provided in ActDocument.java in method: startStopTryGetPoint
public static void setOnNewLocationListener(
        OnNewLocationListener listener) {
    arrOnNewLocationListener.add(listener);
}

public static void clearOnNewLocationListener(
        OnNewLocationListener listener) {
    arrOnNewLocationListener.remove(listener);
}

// This function is called after the new point received
private static void OnNewLocationReceived(float myValue) {
    // Check if the Listener was set, otherwise we'll get an Exception when
    // we try to call it
    if (arrOnNewLocationListener != null) {
        // Only trigger the event, when we have any listener
        for (int i = arrOnNewLocationListener.size() - 1; i >= 0; i--) {
            arrOnNewLocationListener.get(i).onNewLocationReceived(
                    myValue);
        }
    }
}
}

And register it in your Activity like this:

 OnNewLocationListener onNewLocationListener = new OnNewLocationListener() {
            @Override
            public void onNewLocationReceived(float myValue) {

                //use your value here

                MyService.clearOnNewLocationListener(this);
            }
        };

        // start listening for new location
        MyService.setOnNewLocationListener(
                onNewLocationListener);

For more information look at this link: https://stackoverflow.com/a/7709140/779408

How is this related to my question? I'm just trying to pass a primitive float value. — Karthik Balakrishnan, Jan 14 '13 at 13:25
@Torcellite you must customize it. I changed it. look at it again. — Bob, Jan 14 '13 at 13:28
Torcellite's question is how to pass parameter from service to a "to be newly created activity". The answer is how to pass parameter or anything to a already running activity. — fangzhzh, May 01 '14 at 13:35

Passing parameters between service and activity

2 Answers2