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Question

Its very hard to describe my problem but I'll do my best <<

when I want to make a ViewPager in MainActivity , I go to xml then :

<android.support.v4.view.ViewPager
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/viewPager"
    />

then I make an Adapter

public class MyAdapter extends FragmentPagerAdapter

here , I need to import

android.support.v13.app.FragmentPagerAdapter;

the QUESTION is ;

is there any problem when I use v4 , v13 on one application

note : I add the v13 library and make it as (provided)

Answer 1

Edit: There shouldn't be a problem using both, just don't set it as provided. Use compile as the classes are not provided by the system.

Answer 2

On one hand you can use both v4 and v13 support packages . Sometimes you have to.

For example android.support.v13.app.FragmentPagerAdapter and android.support.v4.app.FragmentPagerAdapter are similar but not identical : they don't use the same kind of fragments (native android.app.Fragment vs support android.support.v4.app.Fragment ).

So if you want to use a ViewPager with native fragment you have to extend the v13 FragmentPagerAdapter and set it on the ViewPager (v4, there is only one). Of course this will only work on v13+ devices.

On the other hand you don't have to declare both library : the v13 support lib includes the v4, adding something like

compile "com.android.support:support-v13:23.1.1"

in your build.gradle gives you access to both v4 an v13 support classes.

By the way, see Fragment or Support Fragment for more details about native vs support fragments.