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What is the best way to build app architecture( activities and fragments)

I am building app right now. I am trying to follow all design patterns and google suggestions for building responsive apps.
Firstly, my app will contain navigation drawer.Of course my app will have several activities. So I have searched the best way to have navigation drawer on all activities, I found that the most correct way is to use some BaseActivity class which will have navigation drawer in its layout and framelaout for storing each activity representation(container for fragment). It can hold fragment, but the problem is that only one fragment.
So I have faced this problem. I am going to design following activity
So as in the picture I wanna to have image slider at the top , and some other layout parts under this slider for example grid layout, list or something other.
I think it would be better to separate image slider and other part, for example when my scree will be in landscape orientation it should be replaced but something other.
Futhermore others activites also gonna to have several independent parts for example list and anything other widget.
But as far as my activities should extend BaseActivity class, they would have only one place(container) for storing fragment.
I have tried to think about ways to solve this problem , and I have only one idea is to create several fram layouts in base activity(equal to max fragments used on child activities) and setting them visible and invisible depending on needs, but this approach pretended to be only way of hidding problem.
I don't know what is the most correct way to implement such type of application, so I need help or advices from more experienced developers to build my app correctly and bring user good experience.
I hope you can help me.
Thanks.

To start with, the container in your BaseActivity does not have to necessarily be a FrameLayout. For example it could easily be a LinearLayout with android:orientation="vertical", so that all fragments you add in it will stack one below the other.
Also each fragment can has other nested fragments in itself (although that's generally not the best practice, as usually it indicates some bad UX decisions).
Both those said, I think you just use the first point I made here. Now if you choose this one, I'd expect the question how to handle tablets and other big screens? Best way to handle them is to create a new landscape layout for your BaseActivity, where the fragments container might be different, for example a RelativeLayout, a LinearLayout with orientation="horizontal" and so on.
Good luck!

When use Android fragments?

I have to write a simple app which will look different depending on the screen size.
On a small screen it would have a list of items and after click it will display details. On a bigger screen it would have a list of items and details next to it.
My question is: should I use fragments to do such an app or just write different layouts and place them in layout-large or layout-land folders?

If it is a new app I would always go with fragments, basically for future proofing your app. You may have a single list now, but later you may want to introduce a menu for selecting different types of lists for example. By using fragments, on a phone you can use two activities, one for selection, and the other for the list, but on a tablet in landscape mode you can place the selection and list side-by-side.
Coding for possible app enhancements and features now, saves you time and headaches later.

You can do it in both way , but the suggested solution is using fragment
check this out :
https://developer.android.com/training/basics/fragments/fragment-ui.html
and this :
http://www.vogella.com/tutorials/AndroidFragments/article.html

You should use Fragments, since Fragments were created for that purpose, besides, if you make 2 layouts, you will have to do 2 completely diferent layouts and that'll mean that the activity would not handle that, at least not in an easy way, so try fragments to achieve that, the official documentation example is a case like yours, that would be enough to believe that the correct way to do it is with fragments.

How and when to use Fragments in applications?

I am very in doubt of the structuring of my application. When to use Fragments is a big question for me still. I understand the concept of fragment, but I would like to know how more experienced programmers use them. Is it really only when there is a specific task the fragment should do?
For instance, POP-UPs, what layout would be better used?
And back to the fragments, do you usually have a skelleton fragment that can be used for more than one thing, and then reshape it to different final forms (minor changes) or would you just use different fragments if the layout changes?

You should use fragments in a few situations but its going to depend on your app really.
If you have a layout that is going to be used in multiple places and the code is relatively the same, that is a very good candidate for a fragment so you can keep code down.
If you are making an app where the layout changes based on orientation or device type (tablet vs phone) then fragments are highly recommended to hold different layouts. It makes it easier to change or show multiple layouts if need be on a tablet.
I'm sure there are more scenarios but I would say these are the basics for fragment decision

The most common way I use them is as a kind of plugin layout for my activities. Let's say I have several activities and all of them need to display an address, phone number and some buttons (call number, launch navigation/gps, etc). I pass the fragment the id and the fragment does the legwork of grabbing the information and populating fields for my activities. This way, if I need to add anything, say an email address, I just need to modify one section of code rather than each activity and layout file.

Change views in android

I'm currently developing a little application that uses a login screen and a main screen. I'd been watching how another developers had been made the screen switch, some developers adds and remove fragments on run time, anothers have an Activity for each view (in my case that will be a MainActivity with the main_activity layout, and the LoginActivity with the login_activity layout). And I don't know wich is the way to go. I think that have a fragment for each view will be the solution with more sense, but I want to listen some opinions before continue.

There might be others who disagree with me, but in my opinion, Fragments are better suited when you want to keep a part of the screen static and change something in the other part (analogous to AJAX in websites).
Activities should be used for individual views in those cases where there is only one thing happening on the application front-end.
On the other hand if you have a Gmail like layout (with static links to Inbox, Sent, etc. on the left hand side and a dynamic list of mails on the right hand side of the screen), Fragments is the answer.
But since you have two different screens for layout and main, in my opinion, it would be neat if you used different Activities for the layouts and used Intents to navigate around.

For two completely different Activitys such as Login and Main I think you want to use two different Layouts and two separate Activitys and no need for fragments. However, you may want to use fragments inside any of them as #swayam suggested depending on what you want to do inside of them. You need to look at the docs and decide which is better suited for your needs. No one can really decide that for you.
Activity
Fragments

Enormous form: how can I do it in Android?

I'm developing an Android Tablet application with Android 3.1 SDK.
I have to implement a form in an Android Tablet. Now I'm doing on one screen with TableLayout, TableRow, TextView, Spinner, buttons, etc.
At this moment I have more than 80 views and then I get a warning about it.
The form is divided into sections and I think I can divide it into tabs but I don't know if I will have the same problem (I'm very new on Android development and now I learning how tabs work).
What do you recommend me? I will have, probably, 160 view or more.

I recommend that you split this huge form into multiple screens / steps somehow, it seems much more useable and managable to me. You could use fragments to hold the steps, and use some paging mechanism to navigate between these fragments. By switching fragments and saving their state you can keep the number of Views on the screen relatively low.
Check out the ViewPager component for this to navigate between fragments by swiping. Or you may use the plain old button based navigation (next/previous step e.g.).
If you really need to display all the form elements on one screen and want to keep the number of instantiated Views, you may be able to do this by using the virtualizing ListView, though it seems quite awkward to me. ListView constructs the rows as needed during scrolling, and you need to tell its adapter that you have X type of rows where X is the number of form-parts.

Why don't you logically break this Enormous form and using something like a Next button show the form in multiple activities. This would keep the screen clean, won't bombard the user with too much of information and finally won't give the warning of excess views on screen.