ViewPager not Loading Fragments when using TabLayout - xamarin.android

Question

I got a simple layout with TabLayout and PageViewer but can't get them to work together
<com.google.android.material.tabs.TabLayout
android:id="#+id/sliding_tabs_emoji"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="?attr/colorPrimary"
app:tabMode="scrollable"
app:tabGravity="fill"
app:tabIndicatorColor="#color/gray"
app:tabIndicatorHeight="1dp"
android:paddingBottom="2dp"/>
<androidx.viewpager.widget.ViewPager
android:id="#+id/viewpager_emoji"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/red"/>
In my Activity OnCreate initializing the following
//Fragment array
var fragments = new AndroidX.Fragment.App.Fragment[]
{
Library.Fun.Emoji.Fragments.Recent.NewInstance(),
Library.Fun.Emoji.Fragments.People.NewInstance(),
};
//Tab title array
var titles = Android.Runtime.CharSequence.ArrayFromStringArray(new[] {
"Recent" ,
"People"
});
var viewPager = FindViewById<ViewPager>(Resource.Id.viewpager_emoji);
//viewpager holding fragment array and tab title text
viewPager.Adapter = new EmojiTabsPagerAdapter(SupportFragmentManager, fragments, titles);
// Give the TabLayout the ViewPager
TAB_Layout.SetupWithViewPager(viewPager);
Toast.MakeText(this, "SET", ToastLength.Short);
TAB_Layout.GetTabAt(0).SetIcon(Resource.Drawable.ic_camera);
TAB_Layout.GetTabAt(1).SetIcon(Resource.Drawable.ic_camera);
Where the Adapter is simple as it could be as following
public class EmojiTabsPagerAdapter : FragmentPagerAdapter
{
private readonly AndroidX.Fragment.App.Fragment[] fragments;
private readonly ICharSequence[] titles;
public EmojiTabsPagerAdapter(AndroidX.Fragment.App.FragmentManager fm, AndroidX.Fragment.App.Fragment[] fragments, ICharSequence[] titles) : base(fm)
{
this.fragments = fragments;
this.titles = titles;
}
public override int Count
{
get
{
return fragments.Length;
}
}
public override AndroidX.Fragment.App.Fragment GetItem(int position)
{
return fragments[position];
}
public override ICharSequence GetPageTitleFormatted(int position)
{
//return titles[position];
return null;
}
}
Tabs are appearing but Fragments are not loading, The results are the following
Where it should load RECENT and PEOPLE fragments on each tab, my Fragment XML is the following
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="300dp"
android:background="#color/green">
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="RECENTS"/>
</RelativeLayout>
And fragment's code is the following (for RECENT)
public class Recent : AndroidX.Fragment.App.Fragment
{
public static Recent NewInstance()
{
var frag = new Recent { Arguments = new Bundle() };
return frag;
}
public override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
// Create your fragment here
}
public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View view = inflater.Inflate(Resource.Layout.fragment_emoji_recent, container, false);
return view;
}
}
Any Idea what am I doing wrong?

Answer 1

I use two Fragments: TabFragment1, TabFragment2 to test. In your code, you did provide the code about SetupWithViewPager.
The code below works well for me.
void setupViewPager(Android.Support.V4.View.ViewPager viewPager)
{
var adapter = new Adapter(SupportFragmentManager);
adapter.AddFragment(new TabFragment1(), "First Fragment");
adapter.AddFragment(new TabFragment2(), "Second Fragment");
viewPager.Adapter = adapter;
viewpager.Adapter.NotifyDataSetChanged();
//viewpager.OffscreenPageLimit(4);
}
In MainActivity, you could set like below.
var tabLayout = FindViewById<TabLayout>(Resource.Id.tabs);
tabLayout.SetupWithViewPager(viewpager);
You could download the source file from the link: https://www.c-sharpcorner.com/article/xamarin-android-create-viewpager-tablayout-floatingactionbutton-supportacti/

Answer 2

Did this work before moving to AndroidX?
I think you may need to pass ChildFragmentManager instead of FragmentManager to your PagerAdapter.