An android activity that sets up a view page that changes background color as you scroll. As seen in https://play.google.com/store/apps/details?id=ch.bitspin.timely

ColorTransformingPagerExample.java

public class MainActivity extends ActionBarActivity {


    private ViewPager mViewPager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        final int[] mColors = new int[3];
        mColors[0] = Color.BLUE;
        mColors[1] = Color.RED;
        mColors[2] = Color.GREEN;

        mViewPager = new ViewPager(this);
        mViewPager.setOffscreenPageLimit(mColors.length/2);
        mViewPager.setAdapter(new PagerAdapter() {
            @Override
            public int getCount() {
                return mColors.length;
            }

            @Override
            public boolean isViewFromObject(View view, Object o) {
                return view == o;
            }

            @Override
            public Object instantiateItem(ViewGroup container, int position) {
                TextView view = new TextView(MainActivity.this);
                view.setText("Page position: "+position);
                view.setBackgroundColor(Color.TRANSPARENT);
                container.addView(view);
                return view;
            }

            @Override
            public void destroyItem(ViewGroup container, int position, Object object) {
                View view = (View) object;
                container.removeView(view);
            }
        });
        setContentView(mViewPager);
        mViewPager.setBackgroundColor(mColors[mViewPager.getCurrentItem()]);

        final ArgbEvaluator argbEvaluator = new ArgbEvaluator();
        mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener(){
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
                if (positionOffset < 1.f && positionOffset > 0) {
                    mViewPager.setBackgroundColor((Integer) (argbEvaluator.evaluate(positionOffset, mColors[position], mColors[position + 1])));
                }
            }

            @Override
            public void onPageSelected(int position) {
                mViewPager.setBackgroundColor(mColors[position]);
            }
        });
    }
}