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Multiple fragment listeners in one activity

Hi I have this one Activity, and I need to send data from it to two different fragments. Is there a way to set this up?
public class MainActivity extends AppCompatActivity implements{ FragmentOne.OnEventListener, fragmentTwo.OnEventListener {
private static String TAG = MainActivity.class.getSimpleName();
So basically I am trying to use one interface and I have all the other methods set up in my two fragments and everything works as intended for fragmentOne. I am just trying to figure out how to make the same listener and interface work for the second interface as well. Is there a way to make it work?
Thanks in advance!

As you wrote, "the same listener and interface", so you don't need to hold two instances of the interface, but just make the mainActivity implements the same one. (if it's not the case post your interface and fragments code).

I assume you are semi-following the android fragment tutorial? Please share the rest of your code.
It should work as long as your activity is correctly implementing both interfaces. Java cannot extend multiple classes but can implement multiple interfaces. However your activity must provide implementation for both of the onEventListeners.

Android Class Diagram UML

I'm trying to create a class diagram for an android project.
I want my classes represent the activities, services and interfaces that I will implement.
There are several questions about it on the web, but I couldn't find a definitive answer.
I know that there aren't specific rules for Android and UML, but I have some doubts.
How can I represent the relationship between an Activity and a AsyncTask ?
How can I indicate that an Activity has an intent to another Activity ?
Maybe if someone has an example, will really help.

Maybe something like this?
MyBackgroundTask IS A AsyncTask
MyActivity IS A Activity
MyActivity HAS ONE MyBackgroundTask
You can use a dependency to show that there is an relationship between the AnActivity class and the AnotherActivity class:
In this case, it means that the AnActivity class requires the AnotherActivity class for its specification or implementation. Also, use notes to make it clear.
Update:
Another example:
MainActivity IS A FragmentActivity
MainActivity HAS SOME fragments. The fragments are of type String.

How do I extend two classes

I have this android application and I am trying to extend two classes at the same time. I have this code:
public class TimelineFragment extends Fragment {
public class TimelineFragment extends Activity {
//all codes here
}
}
On my second TimelineFragment, it has an error that says: The nested type TimelineFragment cannot hide an enclosing type

I have this android application and I am trying to extend two classes at the same time
That is not possible. Java does not support multiple inheritance.
I have this code
Given your class name is TimelineFragment, one presumes that it should extend Fragment. Whatever problem you are trying to solve via multiple inheritance will need to be solved in some other way. For example, if you are trying to perform operations on the activity that hosts your fragment, you can call getActivity() from the fragment.

Multiple inharitance is not possible in Java, and therefore in Android.

multiple inheritance is not possible in java so therefore u cant't use it in android as well.
Well one thing you can do is to create interfaces instead of class and implement any no. of interfaces you want and their methods.

Android: How to call a a Class within the Current Class

I'm working on an application that has multiple Activities, and I'm tired of running back and forth between the Manifest and XML layout and stuff. Is there a way to have
Intent intent = new Intent(MainActivity.this, MainActivity.Settings.class);
Or something? Because I've tried it, it doesn't throw me an error, but it just force closes the application. I'm able to bundle all my classes from different .java into one, for ex.
public class MainActivity extends Activity
{
...
#Override
protected void onCreate(Bundle MainActivityState)
{
...
}
public class Settings extends ...
{
...
}
public class Register extends ...
{
...
}
public class Login extends ...
{
...
}
public class BeautifulLady extends personality ...
}

Simple. Just don't even try.
An activity loosely represents a single screen - something the user interacts with. Android is built around this concept and trying to circumvent it will lead to tears.
Stick with it. Having your classes in separate files, and having layout XML separate for each activity, will become your friend and will actually speed things up once you are familiar.
Start with the Activity life cycle document and read it several times until the penny drops. Then expand out from there.
http://developer.android.com/reference/android/app/Activity.html
Object oriented programming, with classes that take care of themselves, is a joy and regardless of which platform you choose to develop on is the way to go for the foreseeable future (old hands, no debates on OOP vs functional please ;)).
If you are going to do mobile development, then the separation of activities, classes and UI is the same concept, just done differently.
See also MVC programming and its' cousins.
http://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller
Good luck.

Perhaps you can define your Activity as 'Single Top', then launch your activity from herself like MainActivity.this.startActivity(new Intent(MainActivity.this, MainActivity.class). It'll then go into onNewIntent() and you will redisplay what you want to redisplay. This way you will have only one screen.

How to extend 2 classes?

This might be a silly question, but I'm struggling on how to make my class extend 2 classes at the same time. I'm trying to make a SERVICE that uses ListActivity. How could I do that?

Java or android Doesn't Support Multiple Inheritance

I assume you are coding in the Java programming language. Then the simple answer is: You don't. Java does not support deriving from multiple classes.
Make your ListActivity contain a Service.
class MyService extends Service{
...
}
class MyList extends ListActivity{
MyService service = new MyService();
}

In Java you can't extend more than 1 class at the same time. However, you can implement more than 1 interface (but this is not about your task).
You should look for bound service

No, it is not possible. You may need to re-architect your implementation.

You can never actually extend 2 classes directly, you need to use a few tricks and make a few interfaces to get it to work. Here is a guide: http://csis.pace.edu/~bergin/patterns/multipleinheritance.html

Assuming you mean this kind of Service, you cannot do this at all; irrespective of Java's lack of multiple inheritance. Services cannot also be Activities. You should create a Service, and a separate ListActivity, and use a binder to communicate between them.
When you do want to inherit the functionality of two classes, use the delegation pattern.