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Calling ShowViewModel on activity, does not show Child fragment

Following the MvvmCross sample here
I am trying to show an activity, that contains a fragment. When I call ShowViewModel on the Activity, I see the activity, without the contained fragment.
If I call ShowViewModel on the Fragment, the Activity AND the Fragment are created.
Does this mean, in order to show a fragment I need to call ShowViewModel on the fragment and not on the parent activity? surly I should be able to call ShowViewModel on the activity and have that create the fragment.
Sorry if i'm missing something here.
Thanks

Start loading url in fragment from othere fragment

I have two fragments in app. When user launch the app, in main layout fragment container shows first fragment, when user click on the button, second fragment replaces first fragment.
I want to do this: when app launch, in second fragment loading some text from the GET url request. And when user click on button to show seecond fragment, all text has already been loaded.
How can I do this ?
Maybe, make function "loadContent" in second fragment and when app launches call this function..
Is anybody have any ideas/info about this, please provide me^)

Make the GET call in Activity's onCreate method. Define your own interface which has an abstract getter. Implement the interface on Activity, and override the getter to return GET response.
In fragment onAttach(Activity) initialize interface like :
Interface callback = new Interface(activity);
now get the data, anywhere in fragment lifecycle after onAttach, from callback object like :
callback.getterFunction();

How to update TextView in a fragment when exiting from another fragment?

So I have a fragment A which has a button to open another a fragment B. In fragment B I can pick some options, which is bundled into an Bundleobject. When I exit from fragment B, I want to refresh a TextView in fragment A.
Right now I'm using dismiss() method to remove the fragment, and then call back the fragment again so that onCreateView() is called. It works fine, but I don't want the animation where the fragment windows is run. So I like to not use dismiss() to remove the fragment instead I want to keep it on the Activity, but I need to know how I can refresh fragment A. I've tried overriding onActivityCreated() but it didn't result in the action I wanted.
So I wonder what's the approach if I want to refresh fragment A without having to dismiss it first so that onCreateView() can be called again.
I can attach code if needed. But maybe just an explanation is enough here?

you can use the life cycle function onResume() in fragment A to update the textview.

You can create your own Listener interface ( example how to do it or this) that listens when you remove your fragment, and you can get the event on Fragment A where you can setText to your TextView.

Fragment without activity

I have been asked an interview question: Can a fragment exist without activity? I searched for answers but didn't get a proper answer and explanation. Can someone help?

Yes, you can do this anywhere:
new YourFragment();
As fragments must have a parameter-less constructor.
However its lifecycle doesn't kick in until it is attached. So onAttach, onCreate, onCreateView, etc. are only called when it is attached. So most fragments do nothing until they are attached.

It can exist as an object in memory (by creating it with new), but it needs to be attached to an Activity in order to appear on the screen, assuming it has any UI (fragments don't have to have UI).

A Fragment can exist independently, but in order to display it, you need the help of an Activity. The Activity will act like a container for the Fragment(s).

A fragment is not required to be a part of the Activity layout; you may also use a fragment without its own UI as an invisible worker for the Activity but it needs to be attached to an Activity in order to appear on the screen.

As soon as you create an instance of the Fragment class, it exists, but in order for it to appear on the UI, you must attach that fragment to an activity because a fragment's lifecycle runs parallel to an activity's lifecycle. Without any call to Activity's onCreate(), there will be no call for onAttach(), onCreate(), onCreateView() and onActivityCreated() of fragment and so it can't be started.

I read above top rated answer , i am not disagreeing but android already provides to make independent fragment without activity DialogFragment , which extends fragment . if you want show in full screen first extends DialogFragment then
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setStyle(STYLE_NO_FRAME, android.R.style.Theme_Holo_Light);
}

Android app must have an Activity or FragmentActivity that handles the fragment.
Fragment can't be initiated without Activity or FragmentActivity.

Dialog Fragment onactivity result

my question is for Dialog Fragment being cshown from a activity, then on the dialog fragment we initiate the onactivityresult(..) the dialog is waiting for result from activity.
when activity top one returns, the dialog fragment is not visible.
the fragment is actually there, under the parent activity who originally showed the fragment.
wired case
in case the orientation were changed when fragment was displayed the flow works flawlessly.
this has only started to happen 4.2 on Nexus 7, any body can help so that the fragment still keeps visible and get the result back

Have you looked at the google documentation on dialog fragments?
http://developer.android.com/guide/topics/ui/dialogs.html
I think the easiest way would be to create an interface for your dialog fragment,
then your caller activity would implement that interface.
Then you can show your dialog fragment by doing something like:
MyDialogFragment dialog = new MyDialogFragment();
dialog.show(getSupportFragmentManager(), "fragment_new");
The documentation has plenty of examples.