Android ViewPager get the current View

Question

I have a ViewPager, and I'd like to get the current selected and visible view, not a position.

1. getChildAt(getCurrentItem) returns wrong View

2. This works not all the time. Sometimes returns null, sometimes just returns wrong View.

   @Override
   public void setUserVisibleHint(boolean isVisibleToUser) {
       super.setUserVisibleHint(isVisibleToUser);
   
       if (isVisibleToUser == true) { 
           mFocusedListView = ListView; 
       }
   }
   

3. PageListener on ViewPager with getChildAt() also not working, not giving me the correct View every time.

How can i get current visible View?

View view = MyActivity.mViewPager.getChildAt(MyActivity.mViewPager.getCurrentItem()).getRootView();
ListView listview = (ListView) view.findViewById(R.id.ListViewItems);

Usurious

Answer 1

I've figured it out. What I did was to call setTag() with a name to all Views/ListViews, and just call findViewWithTag(mytag), mytag being the tag.

Unfortunately, there's no other way to solve this.

Usurious

I can't believe this is the best option but it works. I am just setting the index as the tag when the adapter creates the item. – Pitts

+1 to the absurdity of this solution, but it is definitely the best. Using the position as the tag in PagerAdapter.instantiateView and retrieving the View with findViewBy(getCurrentItem()) is the most elegant form of this hack. – Dysgenics

another +1 @Usurious for finding this solution – Sarazen

I didnt completely understand it. – Northwestwards

@usman for example imageView.setTag(R.string.firstname, "Abhishek"); You have to use application-specific resource id, otherwise there's an error https://mcmap.net/q/111806/-the-key-must-be-an-application-specific-resource-id/1645641 – Hoxie

Please tell me there's a better way to do this almost six years later!? – Asymptotic

Where do I set the tag? This is driving me crazy – Endless

@JoelBroström A place where you inflating a view and returning it, it will be in your pager adapter if using simple adapter or it will will be in onCreateView of a fragment if you are using fragment pager adapter – Overpowering

@GraphTheory, The correct way to do this is by overrideing the onViewAttachedToWindow(holder: Holder) method in adapter class (extension of RecyclerView.Adapter). (my answer: https://mcmap.net/q/110254/-android-viewpager-get-the-current-view) – Psychedelic

Could you show a code example please? Or could one of the commentators post an answer? – Pinchbeck

Answer 2

I just came across the same issue and resolved it by using:

View view = MyActivity.mViewPager.getFocusedChild();

Choice

This wont always work, sometimes focus is elsewhere even tho a view from ViewPager is currently displayed – Sahib

That may be so, but works if you request focus on the page that gets visible – Choice

Unless, im misunderstanding something here. What do you mean specifically by "request focus"? Because if i do mViewPager.getChildAt(i).isFocused() for all children, it reports false for all children. Which is probably because I'm putting this code into the options menu which is a part of the MainActivity, thus moving focus from the ViewPager. Therefore, this way wont work in certain situations. – Sahib

yes, this might be a dialog popup or a Toast object. So use method isVisible() instead – Lilongwe

Doesn't seem to work for AndroidX ViewPager 1.0.0/Support library ViewPager 28.0.0 – Greaser

Answer 3

I use this method with android.support.v4.view.ViewPager

View getCurrentView(ViewPager viewPager) {
        try {
            final int currentItem = viewPager.getCurrentItem();
            for (int i = 0; i < viewPager.getChildCount(); i++) {
                final View child = viewPager.getChildAt(i);
                final ViewPager.LayoutParams layoutParams = (ViewPager.LayoutParams) child.getLayoutParams();

                Field f = layoutParams.getClass().getDeclaredField("position"); //NoSuchFieldException
                f.setAccessible(true);
                int position = (Integer) f.get(layoutParams); //IllegalAccessException

                if (!layoutParams.isDecor && currentItem == position) {
                    return child;
                }
            }
        } catch (NoSuchFieldException e) {
            Log.e(TAG, e.toString());
        } catch (IllegalArgumentException e) {
            Log.e(TAG, e.toString());
        } catch (IllegalAccessException e) {
            Log.e(TAG, e.toString());
        }
        return null;
    }

Agreeable

Thank you so much. It's exactly what I want – Cabal

Answer 4

You can get the current element by accessing your list of itens from your adapter calling myAdapter.yourListItens.get(myViewPager.getCurrentItem()); As you can see, ViewPager can retrieve the current index of element of you adapter (current page).

If you is using FragmentPagerAdapter you can do this cast:

FragmentPagerAdapter adapter = (FragmentPagerAdapter)myViewPager.getAdapter();

and call

adapter.getItem(myViewPager.getCurrentItem());

This works very well for me ;)

Malisamalison

Works only in case your adapter is FragmentPagerAdapter – Angelinaangeline

Note that getItem() is supposed to always return a new instance of a Fragment when subclassing Fragment(State)PagerAdapter. Therefore, this isn't right insofar as it just creates a new instance instead of returning the "old" one. – Conference

The above comment is wrong. Directly from the docs: "Return the Fragment associated with a specified position." Says nothing about returning a new Fragment. – Clause

Your answer returns the Fragment, but for me, the Fragment is empty. adapter.getItem(myViewPager.getCurrentItem()).getView() returns null. – Clause

Answer 5

During my endeavors to find a way to decorate android views I think I defined alternative solution for th OP's problem that I have documented in my blog. I am linking to it as the code seems to be a little bit too much for including everything here.

The solution I propose:

• keeps the adapter and the view entirely separated
• one can easily query for a view with any index form the view pager and he will be returned either null if this view is currently not loaded or the corresponding view.

Angelinaangeline

Answer 6

Use an Adapter extending PagerAdapter, and override setPrimaryItem method inside your PagerAdapter.

https://developer.android.com/reference/android/support/v4/view/PagerAdapter.html

class yourPagerAdapter extends PagerAdapter
{
    // .......

    @Override
    public void setPrimaryItem (ViewGroup container, int position, Object object)
    {
        int currentItemOnScreenPosition = position;
        View onScreenView = getChildAt(position);
    }

    // .......

}

Dapper

Doesn't answer the original question to get the actual view. Also, if you wanted the position why not use getCurrentItem()? – Greaser

Yes. I forgot to write that to get the view you just have to use: getChildAt(currentItemOnScreenPosition). – Dapper

On the other hand, the getCurrentItem() function doesn't return the current selected and visible view, as the original question says, getChildAt(getCurrentItem) returns wrong View. I think the getCurrentItem() function returns the item that is currently computed by the viewPager, and this item may not be the same that is currently on screen – Dapper

Answer 7

viewpager.getChildAt(0)

this always returns my currently selected view. this worked for me.

Boxberry

Answer 8

If you do not have many pages and you can safely apply setOffscreenPageLimit(N-1) where N is the total number of pages without wasting too much memory then you could do the following:

public Object instantiateItem(final ViewGroup container, final int position) {      
    CustomHomeView RL = new CustomHomeView(context);
    if (position==0){
        container.setId(R.id.home_container);} ...rest of code

then here is code to access your page

((ViewGroup)pager.findViewById(R.id.home_container)).getChildAt(pager.getCurrentItem()).setBackgroundColor(Color.BLUE);

If you want you can set up a method for accessing a page

RelativeLayout getPageAt(int index){
    RelativeLayout rl =  ((RelativeLayout)((ViewGroup)pager.findViewById(R.id.home_container)).getChildAt(index));
    return rl;
}

Hooten

getChildAt(pager.getCurrentItem()) doesn't do what you want. For example ViewPager can have 1000 pages, but only 5 childen, so you're going out of bounds if current item is the last page. – Kele

@Kele this is true unless you have the option 'setOffscreenPageLimit(N-1)' where N is the number of pages. This is not advised though if you have many pages because it can be an unnecessary waste of memory – Hooten

Answer 9

Try this

 final int position = mViewPager.getCurrentItem();
    Fragment fragment = getSupportFragmentManager().findFragmentByTag("android:switcher:" + R.id.rewards_viewpager + ":"
            + position);

Bobette

Answer 10

I had to do it more general, so I decided to use the private 'position' of ViewPager.LayoutParams

        final int childCount = viewPager.getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = viewPager.getChildAt(i);
            final ViewPager.LayoutParams lp = (ViewPager.LayoutParams) child.getLayoutParams();
            int position = 0;
            try {
                Field f = lp.getClass().getDeclaredField("position");
                f.setAccessible(true);
                position = f.getInt(lp); //IllegalAccessException
            } catch (NoSuchFieldException | IllegalAccessException ex) {ex.printStackTrace();}
            if (position == viewPager.getCurrentItem()) {
                viewToDraw = child;
            }
        }

Jeromejeromy

Answer 11

I'm using ViewPagerUtils from FabulousFilter:

ViewPagerUtils.getCurrentView(ViewPager viewPager)

Sporran

I'm using this method and I can confirm that it works. – Churchgoer

This is not part of the core android SDK. You are probably using a third party library. That is likely why you were downvoted. – Confirmed

Are you using this library? github.com/Krupen/FabulousFilter. This library has a ViewPagerUtils method. It uses the android.support.v4 namespace which is HIGHLY suspect. You should NEVER EVER use android namespaces for your classes, as it can lead to confusion (this being a perfect example of such confusion). It seems the author did this to access package protected fields, which once again is a terrible code practice. I would not recommend this method. – Confirmed

I wrote in the answer that it's the android support library v4. developer.android.com/topic/libraries/support-library – Churchgoer

And the ViewPager is part of the Support Library so no additional dependency needs to be added. – Churchgoer

ViewPager is part of the support library of course, but ViewPagerUtils does not exist in the support library. – Confirmed

Answer 12

The correct way to do this is by overrideing the onViewAttachedToWindow(holder: Holder) method in adapter class (extension of RecyclerView.Adapter).

Also if you want to perform some operations (freeing up resources, stopping animation listeners etc) on the view which just swiped away, it can be done by overriding the onViewDetachedFromWindow(holder: Holder) in the adapter class.

Psychedelic

This absolutely saved me for the final project of my Android class due in 20 hours. Thank you so much! – Pinchbeck

Answer 13

is that your first activity on the screen or have you layered some above each other already?

try this:

findViewById(android.R.id.content).getRootView()

or just:

findViewById(android.R.id.content) 

also depending on what you want try:

((ViewGroup)findViewById(android.R.id.content)).getChildAt(0)

Harakiri

first twoo just give me the TAB 0 item, all the time, and the third code give me a null – Usurious

tried this? this.findViewById(android.R.id.content).getRootView() Maybe you should give some more info about your activities and how you construct and move between them. – Harakiri

None of those suggestions will work. The 3rd one will get a page in the pager but not the centre view but one to the left and the OP wanted the centred/current page. – Greaser

Answer 14

You can find fragment by system tag. It's work for me. I used it in OnMeasure function.

id - viewPager ID

position - fragment which you want to get

Important! You get this fragment if your fragment was created in adapter. So you must to check supportedFragmentManager.findFragmentByTag("android:switcher:" + id + ":" + position) nullify

You can get view like this:

supportedFragmentManager.findFragmentByTag("android:switcher:" + id + ":" + position).view

You shouldn't give custom tag in adapter

Topmast

Answer 15

You can get it by viewpager listener to get slected item position

viewPager.addOnPageChangeListener(object : ViewPager.OnPageChangeListener{
        override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {
            
        }

        override fun onPageSelected(position: Int) {
            
        }

        override fun onPageScrollStateChanged(state: Int) {
            
        }

    })

Isiah

Answer 16

Use this method.

View getCurrentView(ViewPager viewPager) {
        try {
            final int currentItem = viewPager.getCurrentItem();
            for (int i = 0; i < viewPager.getChildCount(); i++) {
                final View child = viewPager.getChildAt(i);
                final ViewPager.LayoutParams layoutParams = (ViewPager.LayoutParams) child.getLayoutParams();

                Field f = layoutParams.getClass().getDeclaredField("position"); //NoSuchFieldException
                f.setAccessible(true);
                int position = (Integer) f.get(layoutParams); //IllegalAccessException

                if (!layoutParams.isDecor && currentItem == position) {
                    return child;
                }
            }
        } catch (NoSuchFieldException e) {
            Log.e(TAG, e.toString());
        } catch (IllegalArgumentException e) {
            Log.e(TAG, e.toString());
        } catch (IllegalAccessException e) {
            Log.e(TAG, e.toString());
        }
        return null;
    }

it will may return null in androidx if anybody knows the solution comment here

Archy

Answer 17

The issue is you can't call getChildAt(getCurrentItem()) directly on the ViewPager. You should call it on the underlying RecyclerViewImpl which exists at getChildAt(0).

View view = viewPager.getChildAt(0).getChildAt(viewPager.getCurrentItem);

Ornas

Answer 18

Please check this

((ViewGroup))mViewPager.getChildAt(MyActivity.mViewPager.getCurrentItem()));

else verify this link.

Coumas

not working, this get not that View that is visible sadly, and sometimes get null – Usurious

This doesn't work. The range of getChildAt() is different than the range of getCurrentItem(). For example if your ViewPager shows 20 items and 1 offscreen page, then getChildAt()'s range is 0-2 while getCurrentItem()'s range is 0-19. You'd mostly get null return values. – Foreordination

Answer 19

If you examine carefully, there are at most 3 views saved by ViewPager. You can easily get the current view by

view     = MyActivity.mViewPager.getChildAt(1);

Illinium

This doesn't work. What if the viewpager is showing its first or last page? What if there's more than 1 offscreen page? – Foreordination

False, you can set ViewPager to cache more than 3 views with setOffscreenPageLimit(int) – Hetrick