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Android Call Fragment Method from Fragment

I have 4 Fragments and I am trying to click a button on FragmentA and call a method that changes the visibility of some views on FragmentB and populate it.
I tried an interface, but I can't seem to get it to work between 2 fragments. I can call the interface method from a fragment if I implement it in the activity, but I can't implement it in a fragment and call it in a fragment.
Is there a different way to do this? I don't think I can use the static keyword.

I am suggesting you can use broadcast receiver its, good to perform action anywhere and easy to use.
In your first fragment you can define receiver and from another fragment, you can send broadcast or action.
Example are following.
Write following code in your first fragment in which you want to update view,
private void registerReciver() {
broadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
if (intent != null && intent.getAction().equals("UPDATE_FRAG_A")) {
// here you can fire your action which you want also get data from intent
}
}
};
IntentFilter intentFilter = new IntentFilter("UPDATE_FRAG_A");
getActivity().registerReceiver(broadcastReceiver, intentFilter);
}
And In your second fragment write following code for fire action,
Intent intent=new Intent();
// Here you can also put data on intent
intent.setAction("UPDATE_FRAG_A");
getActivity().sendBroadcast(intent);

Assume that all the fragments are in the same activity.
Define a interface in FragmentA, which is a Listener
Expose what you want to do in FragmentB via a public method
Implement FragmentA's interface in the parent activity by calling the public method of FragmentB
For more inforamtion,see Communicating with Other Fragments

how to setup a globally used broadcastreceiver that manipulates views in android

I have a custom title bar used in every activity in my app. I have a broadcast receiver that I want manipulating said title bar,
I have this in my custom application class,
public class MyApplication extends Application {
public static final String ACTION_RESPONSE = "org.company.com.action.MESSAGE_PROCESSED";
private final BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
MyApplication.log("received");
//hide the visible progress dialog spinner in title bar
}
};
public BroadcastReceiver getBroadcastReceiver() {
return receiver;
}
}
I have this in every one of my Activities' onCreate,
MyApplication application = ((MyApplication) getApplication());
registerReceiver(application.getBroadcastReceiver(), new IntentFilter(MyApplication.ACTION_RESPONSE));
What I am trying to do is to find a nice OOP way to do this. I realize that in every activity I can bind a broadcastreceiver that manipulates the view as long as the braodcastreceiver is declared in the activity, but copy pasting that same code 15+ times doesn't make sense to me. Then the next issue is that inside of the MyApplication class, I don't have access to any of the views. Has anyone experienced this issue?

How to pass value to another tab without starting Activity?

I have 2 Tabs - Tab1 and Tab2, Tab1Activity and Tab2Activity.
I want to pass values from Tab1Actvity to Tab2Activity but dont want to start Tab2Activity.
When i try below code it gives null value:
In Tab1Activity
getParent().getIntent().putExtra("key", "value");
In Tab2Activity
String valueString=getParent().getIntent().getStringExtra("key");
System.out.println("Testing.....: "+valueString);

I really discourage you from using global variables by extending the Application class. If your application goes to the background, (e.g. due a phone call) the android system might decide to kill your application. When the call is finished your application and the activity stack will be restored, but your activity state will be lost.
I'd rather suggest you to use broadcasts to send data to another activity.
In your Tab1Activity:
Intent dataIntent = new Intent();
dataIntent.setAction("com.your.app.DATA_BROADCAST");
dataIntent.putExtra("tag", "your data");
sendBroadcast(dataIntent);
Tab2Activity:
BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String yourData = intent.getStringExtra("tag");
}
};
IntentFilter filter = new IntentFilter();
filter.addAction("com.your.app.DATA_BROADCAST");
registerReceiver(receiver, filter);

You definitely want to reconsider using Activities as the content of your tabs. The more standard approach is to use one Activity that uses Tabs to only show part of the layout when a particular tab is selected.
The Android documentation has an excellent worked example, check out Hello, TabWidget.
Alternative
If for some reason you do need to use Activities, you can pass information between them by either adding values to the extras bundle within the Intent your using to open each Activity, or by extending the Application class.
By extending the Application class (and implementing it as a Singleton) you get an object that will exist whenever any of your application components exist, providing a centralized place to store and transfer complex object data between application components.

Also you can use static classes or SharedPreferences for data transfer between tabs.
the correct way is setting a static field into the activity that creates the tabs
public class greformanews extends TabActivity {
public static String JorgesysTitle;
...
...
...
so in your Activity defined in tab 1
#Override
protected void onPause() {
greformanews.JorgesysTitle = "JORGESYS =)";
super.onPause();
}
in your Activity defined in tab 2
//get value defined in Activity 1 !:)
String Title = greformanews.JorgesysTitle

Sending data from one tab to another which contains a spinner

I want to send data from one tab to another. The one which will receive the data contains a spinner. When that data is passed on, I want to the spinner to change its selection to the one given within the data (it'll be the same as one of the spinner items).
Any ideas how I can use Bundle to do this?

is this in same activity or in a new activity ?
Same activity:
make an onClickListener and change the items in the spinner.
New Activity:
use
Inten intent = new Intent(yourclassname.this, targetClassname.class);
intent.putExtra("ID",DATA);
this.startActivity(intent);
it would help if you provide some code, but for now I hope this helps

As option make array holding data for a spinner static and then create a static method in you destination activity something like this:
public static void setSpinnerData (String[] data) {
spinnerData = data;
}
Then call something like this YourActivity.setSpinnerData (myArray);
Alternativerly you can consider saving data to the application object which is the same for all activities.

You may send the data (something small like a string or an ID) using a broadcast.
In the tab where the data is generated
final Intent i = new Intent(IConstants.UPDATE_SPINNER);
i.putExtra(IConstants.DATA_UPDATE, data);
this.sendBroadcast(i)
IConstants.UPDATE_SPINNER and DATA_UPDATE are just Strings used to identify your message by the receiver. You may also put them in your main activity instead of the interface I used.
In the tab with your spinner, declare an inner class for a broadcast receiver, it can access the spinner of the outer class.
private final class MyBroadcastReceiver extends BroadcastReceiver {
#Override
public void onReceive(final Context context, final Intent intent) {
if( IConstants.UPDATE_SPINNER.equals(intent.getAction()) ) {
final String data = intent.getIntExtra(IConstants.DATA_UPDATE, "");
// update your spinner
return;
}
// process other messages ...
}
}
Register the broadcast receiver like this, e.g. in onCreate() or onResume()
this.broadcastReceiver = new MyBroadcastReceiver();
final IntentFilter f = new IntentFilter(IConstants.UPDATE_SPINNER);
// for more actions you can add them like this:
// f.addAction(IConstants.UPDATE_ONOTHER_WIDGET);
this.registerReceiver(this.broadcastReceiver, f);
Remember to unregister in onDestroy() or onPause().
Another option would be to use a handler and send messages to the handler. However, you would need the handler, which is located in the receiver, to be accessible in the sender. This way your fragments or activities (the tabs) would be stronger coupled.

handle SMS- onReceive to trigger event in another activity/class

so, what i'm trying to do is change some ui elements which are expanded in my main activity- and i want the changes to be triggered by the onReceive, which is from broadcastreceiver extended in a different separate class.
I'd like to do something like this
public class SmsReceiver extends BroadcastReceiver {
public void onReceive(context, intent){
MainActivity main = new MainActivity(); //this is my... main activity :)
main.button.setBackgroundColor(Color.green);
}//end onReceive
}//end class
in my MainActivity, i've set values to the GUI button element like this:
public class mainactivity extends activity... implements onclick... bla bla (){
Button button;
onCreate....{
button = (Button)findViewById(R.id.button);
so i'd like to know if when onReceive is activated, can i edit the state of a widget in ANOTHER activity by instantiating that activity and calling a setter method on it?

Your method will not work because you are creating a new instance of MainActivity. This will not reference your currently active main activity. One solution you may try is sending another intent to your activity and implementing onNewIntent(Intent newIntent) in your activity. That way you can update your main activity in that function, try passing extras in with the new information you have received.