Everything is in the title.
On the official documentations it is stated that Note that services, like other application objects, run in the main thread of their hosting process and AsyncTask only works if it is executed in the UIThread.
So is it possible to use AsyncTask in a Service class? code...
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I was wondering if it's possible to call specific methods defined within the AsynTask class from another class and/or service ?
In my specific case I have a Service playing some sounds, but the sound is selected from a List with available sounds...
When a sounds is selected it is downloaded from my home server, this takes some time (not much, let's say around the 3-4 seconds, the sounds/effects aren't big in size)...
So my problem at the moment is that I have a service to play those sounds, and when I select one I wanted to show a progressdialog... The way (if I understood correctly) is to use an AsyncTask, but the only thing the AsyncTask will do is telling my Service to play a specific sound from my server... So there is no "callback" from the service to the Asynctask...
How can I call a running AsyncTask, which sits in another class, and tell him all work is done and thus he can stop showing the ProgressDialog ? Or am I over-engineering it and there are other ways ?
What I want is just to have the AsyncTaskTask showing a progressbar an external class. To do this I am passing the context as you can see in the main class. But whatever I try I get NullPointerException.
Working code examples.
Using Android 2.2 by the way.
main:
CODE:............
Update:
I have a follow up question: Using the above code, is it possible to return a value from the onPostExecute method back to the main class, somehow? (Sorry about beeing noobish)
I have tried something like this:
String result = new AsyncClass(this).execute();
and then a method that return back a string. But I can't do that because i got:
Type mismatch: cannot convert from AsyncTask<String,Void,Void> to String
I am trying to create HTTP connection using AsyncTask class.
Is it possible to create HTTP connection ?
Can you suggest sample source code?
I have a service, that requests another class, which launches an AsyncTask
Service->Weather Class->Execute Method->Asynctask->Execute
this is launched in the service by
new Weather(this).execute(); // the execute is a method of the class, not of the AsyncTask
how do I detect in Service that the AsyncTask finished so I can call stopSelf?
I have a Service that creates AsyncTasks for downloading files. In activities, we create Runnables or Threads that we pass to Activity.runOnUiThread(). I can't access that method from a service, so how do I use AsyncTask correctly, (do heavy work without blocking the UI Thread)?
View 1 Replies View RelatedI have an activity which starts a service. In the service there is a network lookup in an AsyncTask. Results from the lookup are saved to a database.
The activity queries to database and shows the newest entries. But at the very first run the database is empty, so there is nothing to show. In this case I would like to show a progress dialog to the user while the network lookup is taking place. I would like to dismiss the progress dialog when the first lookup is finished.
Is there a way to access the progress dialog created in the activity from the service? Or how to do it?
I need a endless loop/while/for.How to do this in a AsyncTask or Service?
[HIGH]public class Back extends AsyncTask<Void, Void, Void>{
@Override
protected Void doInBackground(Void... params) {
handler.postDelayed(new B1(), 2000);
handler.postDelayed(new B2(), 3000);
return null;
}
}[/HIGH]
I want to make my handler endless loop/while/for.
I'm trying to figure out the correct way to create an AsyncTask to retrieve some data from the internet and then to take that data and bundle it up in an Intent and pass it to a new activity(A list display). So in the first activity I just have an EditText and Button. In the event of an OnClick the task should be called and when it is finished the data should be bundled inside an Intent and passed to the next Activity. The problem is when I take the results from onPostExecute and set them to an instance variable of the main activity, that instance variable is still null when the task is complete. Here is the barebones version of the code:
CODE:...........
When I debug the application I see onPostExecute does contain a valid PlacesList full of results, so why is the instance variable places set to null after the task is executed? I am going about "returning data" from an AsyncTask incorrectly?
What is the class name of media scanner service?
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I initially implemented the constructor of the derived class to also take a String argument and passed it along to the derived class. This is wrong. This will cause the startService() call to generated a java.lang.InstantiationException in the application containing the service i.e. you don't get the exception in the application calling startService(). A clue to the actual problem is a little further up in the logs:"newInstance failed: no <init>()"
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public MyIntentService() { super("MyIntentService");
} @Override
protected void onHandleIntent(Intent intent) {
// Handle events on worker thread here }
I am trying to call my service class's stopService() method from my activity. But I don't know how to access stopservice method from my activity class. I have the below code but its not working. This is HomeScreen class:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
enablecheck = (CheckBox)findViewById(R.id.enablecheck);
enablecheck.setOnCheckedChangeListener(new OnCheckedChangeListener(){
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if(enablecheck.isChecked()){
startService(new Intent(HomeScreen.this, AutoService.class));
} else {
stopService(new Intent(HomeScreen.this, AutoService.class));
} } });
}
This is Service Class:
public class AutoService extends Service {
private static final String TAG = "AutoService";
private Timer timer;
private TimerTask task;
@Override
public IBinder onBind(Intent intent) {
return null;
} @Override
public void onCreate() {
Toast.makeText(this, "Auto Service Created", Toast.LENGTH_LONG).show();
Log.d(TAG, "onCreate");
int delay = 5000; // delay for 5 sec.
int period = 5000; // repeat every sec.
timer = new Timer();
timer.scheduleAtFixedRate(task = new TimerTask(){
public void run() {
System.out.println("done");
} }, delay, period);
}
@Override
public boolean stopService(Intent name) {
// TODO Auto-generated method stub
timer.cancel();
task.cancel();
return super.stopService(name);
} }
Hi, custom classes which are part of a framework, so nothing graphical. One of those (singleton) classes is a Logging class which send logs to my server. I noticed that even though I can call the classes methods in my service it actually won't be logging anything... In my specific example it's osmething like : Logger.getInstance().log("Whatever I want to Log"); Obviously the getInstance is a static method so it can be accessed from anywhere within my project right away.. I was wondering though why this method for example isn't getting called ? Also how do I debug a Service ? Btw I am using of IPC from one of my Activities which gets bound to the service and can start/stop the music for example...
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View 3 Replies View RelatedI am trying to create a drools app on android using eclipse. It compiles /builds correctly in Eclipse. But when I run it in emulator or android device, it says
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View 2 Replies View RelatedWhat I want to do, is be able to access the object neoApi inside the Neoseeker class, from its inner class RunningTimer. Now, in my code, you can see what I would think to work, but when I run my application, nothing pops up. Nothing inside my TextView, no Toast, nothing at all. How can I remedy this?
package com.neoseeker.android.app;
import java.util.Timer;
import java.util.TimerTask;
import org.json.JSONObject;
import android.app.Activity;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;.......................
I'm new to Java and android development. In my application I need data which is accessible for a few activities. I've read that a good solution is to use Application class for this. So I use it like this:
public class MyApplication extends Application {
private String str;
public String getStr(){
return str;
}
public void setStr(String s){
str = s;
}
}
and I can access this variable from activity like this:........................................
I have just started android. I just want to know that how can i call activity class from other java class. i just want to pass class object to activity class.
public class GsonParser extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
MagazineThread thread=new MagazineThread();
thread.start();
}
public GsonParser(JsonMagazineParser Obj)
{
}
}
and i am just doing like from other class. GsonParser obj=new GsonParser(this);passing obj to activity class.how can i achieve that.
In my app in one package there are some classes. from those classes i want to run one class that is the Gps functionality class. i want to run that class in background. how i do it, i don't know. i am not able to make it solve from any document. if anybody knows the way to solve it please me by run a "hello world" app in the background. i am not able to solve this problem by going through document.
View 2 Replies View RelatedI'm building a small Android application, but this is more of a Java question than an android question. Looking through the tutorials there are lines that look like: startService(new Intent(this, MyService.class));
What exactly does the "MyService.class" field represent? Is that just a reference to the class for a template?
I made a Dialog Class with it's view classI want to pop up the dialog when I got some packets from network. so I made a Thread which parses packets and then I made if clause in Run() method There is no problem with parsing packet but when I enter "if clause" and call showDialog() I got Error message
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I created a method called insertTable in a class called Table but i can't use it in my onClick method in the main class :
CODE:.......
I want to do a income.insertTable in the onClick method but eclipse say that i need to create a local variable.
I am working on a simple application (studying purposes) which list all the files from a selected folder. On top of that I would like to have a search feature where the user can search for files (the code for that is already in place). Now, I was thinking about having the search running in the background somehow, whilst the user can still navigate, create folders, copy, sort and do other stuffs normally. When the search finishes the user would get a notification and then could click on it and go to that activity (It ideally should be the same ListView I already use for browsing the files, I would just need to update the Adapter there with the latest processed data after clicking in the notification). What's the best answer for that? Threading or AsyncTask?
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