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Get activity that called parent activity of a Fragment

In my fragment I have a 'dismiss' button that should behave in a different way dependent on which Activity called its parent activity (say TutorialActivity).
In the TutorialActivity I am already determining which Activity called it. How to pass that data down to the fragment?
My fragments reside in a PagerAdapter and I wouldn't like to need to pass this info as a 'newInstance()' parameter every time, as it seems an overkill, taking into consideration that this parameter would be the same for each fragment in my FragmentStatePagerAdapter.

You can access the variable from Tutorial Activity by making this variable public. Suppose variable name is parent. You can access it by using instance of TutorailActivity (suppose instance of Activity used in fragment is mTutorialActivity) then it should be like mTutorialActivity.parent.
But you need to pass instance of TutorialActivity as it may be used for other purposes also like fetching strings from strings.xml and other purpose. So it would be beneficial to pass Activity instance instead of variable.

What I ended up doing: I implemented said "different behavior" in the TutorialActivity itself, having moved the dismiss button up from the fragment. Then a simple onClickListener and a switch statement inside of it.

Who will be create on object for Activity?

I am new to android.I need some clarification about Activity and Activity life Cycle.
My Questions are:
1.Who is going to create an object for Activity.
2.Who is calling all life cycle methods of android.Please can any one clarify it.
Thanking in Advance.

You cannot just create objects of Activities by using:
MyActivity activity = new MyActivity();
Android itself call at runtime both activity and its lifecycle..
as you would with normal Java classes. All Activities in Android must go through the Activity lifecycle so that they have a valid context attached to them.
By treating an Activity as a normal Java class, you end up with a null context. As most methods in an Activity are called on its Context, you will get a null pointer exception, which is why your app crashes.
Instead, move all such methods which need to be called from other classes into a Utility class which accepts a valid context in its constructor, and then use that context in the methods to do the work.
LifeCycle of Activity:

How to get current focus view object in Service?

How can i get the current focus view in my Service.
I found some methods to do this, like Activity.getCurrentFocus() and
Windows.getCurrentFocus().
But these methods are used in a Activity.
If I want to use these, I have to get the current focus activity.
I tried to use WindowManager to get current task.
It only got the current Activity's class name in this way. not
Activity Object.
List<RunningAppProcessInfo> rList =activityManager.getRunningAppProcesses();
RunningTaskInfo rt = rtList.get(0);
rt.topActivity.getClassName(); // the class name of the current Activity
How can I use these methods to get the current focus View in a
Service? Or is there another way to
do?

A service is a background work, so is not tied to any UI.
What you can do is bind your service to an Activity and call some method (through an interface) on this activity to return the focused view of this activity.
Anyway, can you explain better what you want to achieve? normally a Service don't apply to do things with UI, so maybe there is a better way to do what you want.

Android - Parent activity should determine what child activity had called it

I have 2 activities in my project, lets say Activity A, and Activity B. Both A and B extend the same superclass: BaseActivity.
We know that in this case, lets say if the Activity A is opened, then the superclass method onCreate() is called, and then the Activity A's onCreate() follows.
Being in the onCreate() method of the parent BaseActivity class, how can I determine which child activity has been started?

I would suggest a different approach. Basically don't do inheritance. Use composition instead. Remember most operations that you think you need to extend for really just need a reference to the context. Activities extend from context. So really you can provide most base functionality in any class that has reference to an active context. No need to do inheritance at all.
So if you want to share some functionality between ActivityA and ActivityB just put it in HelperC
HelperC.someOperation(Context c, otherParams)
HelperC can do anything that some base activity could do. Ultimately the base activity will never exist any way. It will always be an instantiated version A or B

I don't think you should do it this way.
As far as I remember the idea of extending, superclass method should contain only universal code. Puttin the differenting code in child classes would be much easier to do and as I believe more proper.
You can initilize some values in parent onCreate(), and then re-set it in childs'.

Android: Access method in an activity from another activity

My launch activity starts up another activity whose launch is set to single instance. In this 2nd activity, I have a public method. I then start up a 3rd activity and that activity needs to access the public method in the 2nd activity. I don't want to use startActivity and pass it extras because I assume the onCreate will get called (or am I wrong?) and I need to avoid the 2nd activity from reinitializing itself.
When an activity is started using startActivity, is it possible to gain access to the underlying class instance itself and simply call the method?

I actually came up with a simple solution. As a matter of fact you can access the underlying class of an activity. First, you create a class that is used to hold a public static reference to activity 2. When activity 2 is created, in its onCreate method you store "this" in the static reference. Activity 2 implements an interface with the methods that you want available to any other activity or object. The static reference you hold would be of a data type of this interface. When another activity wants to call a method in this activity, it simply accesses the public static reference and calls the method. This is no hack but is intrinsic to how Java operates and is totally legitimate.

It is not a good idea.
As I can understand method from second activity is actually not connected to particular activity while you want to call it from another one. So carry the method out to other (non-activity) class (maybe static method) and use it from both activities.

It's not directly possible to gain access to activity object started using startActivity (without using some hacks). And frankly you shouldn't even trying to accomplish this.
One Activity component can cycle through several Activity java object while its alive. For example, when user rotates the screen, old object is discarded and new activity object is created. But this is still one Activity component.
From my experience, when you need to do things you described, there is something wrong with your architecture. You either should move part of activity's responsibilities to Service or to ContentProvider, or use Intents, etc. Its hard to recommend anything more specific without knowing more details.

No there is no way to pass a reference via startActivity() however you can use some sort of shared memory to keep reference to your Activity. This is probably a bad design. However passing an extra with your Intent will not cause onCreate, that is completely related to the lifecycle.