I need to share data between a local service and its hosting activity,
I am using sendBroadcast in order to send data to the hosting activity from the service, but what if I wanted to send data back to the service from the hosting activity?
So I though of creating a static method on the service, and call it from the activity, and through it send the parameter, but then I can't do operations like show a toast inside that static method (which is inside the service)...
This is because you can't use myclass.this inside a static method, I guess there are more limitations...
Maybe there is another solution? Maybe there is a proper way for this task?
Thanks,
moshik.
You could create a sharedpreferences file and store the data in there. That way both activity and service will be able to access and update the same data
I'm not too sure on your use cases, however another option (aside from using intents / shared preferences) is to extend the Application class and put your object onto that.
The benefit of this is that you don't need to worry about intents, but it may not be the best option for your scenarios.
I wrote a tutorial here, give that a try
*disclaimer : this is just one way to solve an issue, not THE way..
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I try to get the foreground activity for a long time, and i didn't managed to get it until now.
I don't know if it even possible, but i am dont intersted in my app activity only.
There is no data transfer between my service and the activity which i want to get.
I saw lot of questions of this kind but i got nothing suitable for my needs.
I just need to get an instance, not a ComponentName, not decription of the current foreground activity.
I've tried through ActivityThread, ActivityManager, ActivityManagerService (even though i couldnt get his instance too), and so on.
Field activitiesField = activityThreadClass.getDeclaredField("mActivities");// won't help
activityManager.getRunningTasks(rnd);// won't help either
If there is any refelection way, listener or something like that, but not a static field.
Without knowing why you want an instance of the Activity, or other background info. I'd suggest the following.
If you're inside a Fragment, then you can do getActivity() - which will give a reference to the Activity, and you can then cast this as your own Activity.
Otherwise, you might want to consider having a BroadcastReceiver, which can start an Activity for you.
You shouldn't be accessing an Activity directly. If you have methods/logic you need to access, you might consider refactoring them into a helper class.
Edit:
"Your application runs in a secure sandbox environment, so other processes on the system cannot access your code or private data." Take from the official Android docs
I'm using IntentServices to call a restful service and then turn over the result to a receiver. The back-end requires a user id and authentication token, which I stored in a singleton class. I've run into issues with this singleton being cleaned up when the process is terminated, and its data isn't around when Android tries to restart my activities. User preferences seem like a great place to start this kind of data, but those require a reference to your context.
Where can I put this data so it can be accessed outside of the view? I realize I could just pass it with every single Intent that triggers my IntentService, but am hoping there's a better way.
Thanks!
Service is a ContextWrapper which is a Context so you can use the keyword this when getting an instance of your shared prefs.
For lightweight data such as a few strings etc, SharedPreferences is fine. Just pass any context, every component has one or is one itself. Or pass the application context. Lack of context shouldn't be an issue. Pass it along into your singleton as a parameter.
Using a database, or inventing a proprietary storage mechanism using a file, or creating a content provider, all seem overkill to me.
If you don't want to pass it all the time (which is not that bad), and you still want to stay in the Android framework philosophy, create a ContentProvider for this task.
Or you can go full classical and save them in some file. Or in a sqlite database (Android offers easy support for this).
I have a main Activity that's happily been working with a Service I created for a while now. Recently I've had to add a DialogFragment to my app and although its working nicely as well, I now need to make a call to my Service and pass along more than the usual Intent type strings. Basically I need to pass an array of Bitmaps to the Service, and I don't think it's reasonable to try and stuff them into an Intent.
So I was hoping, without luck so far, that I could bind to the service while the DialogFragement is open so I can make a direct method call to the Service.
Is there any way to do this? So I have to copy the entire ServiceConnection class and bind to it from onStart()? I figured there must be a less messy way to do this.
Thanks in advance.
As there is no code, I assume that your DialogFragment serves to capture some kind of input from the user (Yes/No or something similar), as most dialogs do. If this is the case, then you can simply return the input back to the calling Activity and make a call to the Service based on this input. Another question is where to the Bitmaps come from? Passing an array of Bitmaps from an Activity to a Service doesn't seem a good decision for me, you should probably consider moving the Bitmap retrieving logic to the Service itself, whether the Bitmaps come from the network or from resources.
Most part of my answer is based on assumptions about the design of your application, so if those assumptions go wrong you can post some code or add a broader description of your app and I'll be glad to review my answer.
I would like to get the class name (*.class) of an Activity which is bound to my local Service. Is there any native method which i could use to achieve this?
I tried to get that information out of the Intent I use to bind to the Service. But it seems there is no function in Intents for this.
If I wasn't blind, additionally I would like to know why there's no information about the calling Activity in an Intent?
Is there any native method which i could use to achieve this?
No, in large part because the class in question may not exist in your app, and may not even be a class.
You are welcome to package whatever identifying information you would like in the Intent, such as via an extra.
Also, if you are allowing third parties to bind to this service, you can use methods like getCallingUid() on your Binder to find out information regarding the process that bound to you.
additionally I would like to know why there's no information about the calling Activity in an Intent?
Because there is not necessarily a calling Activity. The binding engine works with C; C does not have classes, let alone activities.
In my application, I have one activity, which connects to the server and gets certain user information from it. Then, it launches another activity where that information should be processed.
What is the correct way to pass data between activities in Android?
If that data is only needed once, you should use an Intent. Here is a tutorial on it.
If it needs to be accessed all the time, you can put it in an Application subclass or some other singleton.
In general you can use methods like putExtra, to attach data to an Intent, and then use
for example getIntent().getStringExtra(name) to retrieve it in the other activity.