IssueTracker

I face with the same problem. I have different pageMargin in landscape and portrait and when viewpager is scrolled for the more than first position, after rotating device it is shifted.

I beleive the problem is inside onSizeChanged that is called after onConfigurationChanged, it has following code:
        if (w != oldw) {
            recomputeScrollPosition(w, oldw, mPageMargin, mPageMargin);
        }

w always not equals oldw when changing orientation, so recomputeScrollPosition is called, but whit the same values for margin and oldMargin.
This should be fixed.

[Comment deleted]

I found the same problem in suport library v4, wrong align happens only when ViewPager has a page margin > 0.

[Comment deleted]

The issue is still reproducible in support library v4 (rev. 18).

I managed to fix the issue by importing the source code of ViewPager in my project and modifying from onSizeChanged method the following line:

From:
   if (w != oldw) {
       recomputeScrollPosition(w, oldw, mPageMargin, mPageMargin);
   }

To:
   if (w != oldw) {
       recomputeScrollPosition(w, oldw, 0, 0);
   }

I use this little wrapper as a work around for the bug:

ublic class FixedViewPager extends ViewPager {

        public FixedViewPager(Context context, AttributeSet attrs) {
                super(context, attrs);
        }

        public FixedViewPager(Context context) {
                super(context);
        }
       
    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w-this.getPageMargin(), h, oldw-this.getPageMargin(), oldh);
    }
}

Thanks for posting the workaround. Works great. Can't believe this issue still exists after almost 2 years since it's been reported.

Greats !!