How to programmatically show next view in ViewPager?

Question

I created a ViewPager and everything is working fine, however I want to have a previous next button outside of ViewPager which can be used to navigate inside ViewPager. How can I go to next Item on ViewPager without swiping manually?

Rite

Doesn't this work viewpager.setCurrentItem(int index); ? – Salaidh

it did , I suppose this question is a duplicate. – Rite

Possible duplicate of How to change ViewPager's page? – Meneses

Answer 1

As blessenm answered viewpager.setCurrentItem(int index) is the way to go.

Rite

Unfortunately I do get different behavior, when the user swipes manually and when I jump using setCurrentItem. The order of calls is reversed. When I swipe, it first calls OnPageChangeListener#onPageSelected and then it calls setUserVisibleHint in the fragments. If I use setCurrentItem, it first calls setUserVisibleHint in the fragments and then it calls OnPageChangeListener#onPageSelected, which really is a problem in my case :/ so I was hoping to find a way to keep the natural behavior but still programmtically move to another page. – Hellman

@Vaibhav what if I want to show the next view of activity – Bank

@Hellman Did you manage to find a solution for this issue ? I also see this weird behavior but can't find a way to keep the flow of the regular swipe when I programmatically switch to the next/prev fragment. – Brittney

@Gil I am afraid not - i removed the programmatical changing of the current view and just allowed swiping. However we completely changed the implementation later so I didn't pursue this issue any further. – Hellman

Answer 2

A complete implementation just for completeness:

public void MoveNext(View view) {
    //it doesn't matter if you're already in the last item
    pager.setCurrentItem(pager.getCurrentItem() + 1);
}

public void MovePrevious(View view) {
    //it doesn't matter if you're already in the first item
    pager.setCurrentItem(pager.getCurrentItem() - 1);
}

Mourant

You might need it. For instance, if the change is triggered by a click, you could use (nextBt.getId() == view.id) to know what caused it – Gathers

@Sagar he might have set the click listener of button in xml, in that case you must have the view parameter, even if you don't need it. – Chiarra

page swiping animation not coming? – Disquisition

Answer 3

Easiest way is:

nextButton.setOnClickListener { pager.arrowScroll(View.FOCUS_RIGHT) }
prevButton.setOnClickListener { pager.arrowScroll(View.FOCUS_LEFT) }

Hypsometry

Answer 4

i fix it Better, ty Androiderson.

  private void MoveNextTopSlideShow(View view)
    {
        if (_viewPager_TopImageSlide.CurrentItem == _viewPager_TopImageSlide.ChildCount)
        {
            if (_viewPager_TopImageSlide.ChildCount > 0)
            {
                _viewPager_TopImageSlide.SetCurrentItem(0,true);
            }
        }
        else
        {
            //it doesn't matter if you're already in the last item
            _viewPager_TopImageSlide.SetCurrentItem(_viewPager_TopImageSlide.CurrentItem + 1, true);
        }
    }

    private void MovePreviousTopSlideShow(View view)
    {
        if (_viewPager_TopImageSlide.CurrentItem == 0)
        {
            if (_viewPager_TopImageSlide.ChildCount > 0)
            {
                _viewPager_TopImageSlide.SetCurrentItem(_viewPager_TopImageSlide.ChildCount-1, true);
            }
        }
        else
        {
            //it doesn't matter if you're already in the first item
            _viewPager_TopImageSlide.SetCurrentItem(_viewPager_TopImageSlide.CurrentItem - 1, true);
        }
    }

Bizarre

Answer 5

viewPager.setCurrentItem(currentStep, true), where the second parameter it's boolean smoothScroll.

Callery