Determine when a ViewPager changes pages

Question

I have three pages (Fragments) inside a ViewPager, however I only want to display a menu item for two of those pages.

The code given in a previous SO answer does not seem to work:

@Override
public void setUserVisibleHint(boolean isVisibleToUser) {
    super.setUserVisibleHint(isVisibleToUser);

    if (isVisibleToUser == true) { }
    else if (isVisibleToUser == false) {  }

}

Eclipse says @Override isn't needed and super can't be set. It's never called by the system, and even if it was how would I determine which page was being shown at the moment? Could I have some help here?

This one worked for me, and gives a little more context about how to use the given solution: [Detect ViewPager tab change inside Fragment](http://stackoverflow.com/questions/9779397/detect-viewpager-tab-change-inside-fragment). — gcl1, Nov 30 '12 at 17:15

score 326 · Accepted Answer · edited Dec 03 '17 at 19:33

326

Use the ViewPager.onPageChangeListener:

viewPager.addOnPageChangeListener(new OnPageChangeListener() {
    public void onPageScrollStateChanged(int state) {}
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {}

    public void onPageSelected(int position) {
        // Check if this is the page you want.
    }
});

edited Dec 03 '17 at 19:33

chinmish

99
1
11

answered Jul 02 '12 at 13:16

Joru

4,406
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54

You can use a SimpleOnPageChangeListener instead and only override onPageSelected – clocksmith Jul 15 '14 at 16:24

score 126 · Answer 2 · edited Jul 08 '15 at 17:26

126

ViewPager.setOnPageChangeListener is deprecated now. You now need to use ViewPager.addOnPageChangeListener instead.

for example,

viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
        @Override
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

        }

        @Override
        public void onPageSelected(int position) {

        }

        @Override
        public void onPageScrollStateChanged(int state) {

        }
    });

edited Jul 08 '15 at 17:26

Ryan C

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answered Jun 16 '15 at 12:32

Jaydipsinh Zala

16,558
7
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4

I seem not to understand. Am an absolute beginner. So what do we put inside those methods. Please help me on where to learn `addOnPageChangeListener`. – Karue Benson Karue May 14 '16 at 02:20
+1 for the info, but what is the difference of these two `ViewPager.SimpleOnPageChangeListener` and `ViewPager.OnPageChangeListener` as what mention above? – RoCkDevstack Jun 13 '16 at 11:28
2

@RoCk With SimpleOnPageChangeListener you only need to override the methods you actually want to use. See http://stackoverflow.com/a/31961397/608312 for example. – Jake Lee Sep 10 '16 at 07:32

score 44 · Answer 3 · edited Sep 22 '19 at 04:47

For ViewPager2,

viewPager.registerOnPageChangeCallback(object : ViewPager2.OnPageChangeCallback() {
  override fun onPageSelected(position: Int) {
    super.onPageSelected(position)
  }
})

where OnPageChangeCallback is a static class with three methods:

onPageScrolled(int position, float positionOffset, @Px int positionOffsetPixels),
onPageSelected(int position), 
onPageScrollStateChanged(@ScrollState int state)

Hemant Sharma · Answer 4 · 2016-02-01T04:45:52.360

40

You can also use ViewPager.SimpleOnPageChangeListener instead of ViewPager.OnPageChangeListener and override only those methods you want to use.

viewPager.addOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {

    // optional 
    @Override
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { }

    // optional 
    @Override
    public void onPageSelected(int position) { }

    // optional 
    @Override
    public void onPageScrollStateChanged(int state) { }
});

Hope this help :)

Edit: As per android APIs, setOnPageChangeListener (ViewPager.OnPageChangeListener listener) is deprecated. Please check this url:- Android ViewPager API

edited Feb 01 '16 at 04:45

answered Aug 12 '15 at 09:36

Hemant Sharma

1,239
12
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1

As `mViewPager.setOnPageChangeListener();` is deprecated now, this one is working fine. – BST Kaal Nov 23 '15 at 07:09
In the above code, to detect whether a state has changed save the current position and compare it when the page is scrolled in onPageScrolled method. – AnupamChugh Feb 27 '18 at 12:14

Kishan Solanki · Answer 5 · 2020-05-15T07:41:32.403

Kotlin Users,

viewPager.addOnPageChangeListener(object : ViewPager.OnPageChangeListener {

            override fun onPageScrollStateChanged(state: Int) {
            }

            override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {

            }

            override fun onPageSelected(position: Int) {
            }
        })

Update 2020 for ViewPager2

        viewPager.registerOnPageChangeCallback(object : ViewPager2.OnPageChangeCallback() {
        override fun onPageScrollStateChanged(state: Int) {
            println(state)
        }

        override fun onPageScrolled(
            position: Int,
            positionOffset: Float,
            positionOffsetPixels: Int
        ) {
            super.onPageScrolled(position, positionOffset, positionOffsetPixels)
            println(position)
        }


        override fun onPageSelected(position: Int) {
            super.onPageSelected(position)
            println(position)
        }
    })

Determine when a ViewPager changes pages

5 Answers5

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