How to achieve a ViewPager with previous and next page shown and bigger focused page

Question

I'm trying to create something that will display my pages on a viewpager for it to have nice feel and design and I checked out this link which somehow helps and also follow this link on how I can implement it but I ended up with some issues. First is that it won't really work or look that good for devices that runs below API11 (API8 is my target). and Second is that I can't manage to make the focused page to be bigger than the next and previous page. I wanted it look something like this for the sake of design:

Hope someone can help me on this or any other way to achieve this.

Answer 1

Read this first. Then apply your own PageTransformer implementation. Something like this:

public class DepthPageTransformer implements ViewPager.PageTransformer {
    private static final float MIN_SCALE = 0.5f;
    private static final float MAX_SCALE = 0.8f;
    private static final float MIN_FADE = 0.2f;

    public void transformPage(View view, float position) {
        int pageWidth = view.getWidth();

        if (position < -1) {
            view.setAlpha(MIN_FADE);
        } else if (position < 0) {
            view.setAlpha(1 + position * (1 - MIN_FADE));
            view.setTranslationX(-pageWidth * MAX_SCALE * position);
            ViewCompat.setTranslationZ(view, position);
            float scaleFactor = MIN_SCALE
                    + (MAX_SCALE - MIN_SCALE) * (1 - Math.abs(position));
            view.setScaleX(scaleFactor);
            view.setScaleY(scaleFactor);
        } else if (position == 0) {
            view.setAlpha(1);
            view.setTranslationX(0);
            view.setScaleX(MAX_SCALE);
            ViewCompat.setTranslationZ(view, 0);
            view.setScaleY(MAX_SCALE);
        } else if (position <= 1) {
            ViewCompat.setTranslationZ(view, -position);
            view.setAlpha(1 - position * (1 - MIN_FADE));
            view.setTranslationX(pageWidth * MAX_SCALE * -position);

            float scaleFactor = MIN_SCALE
                    + (MAX_SCALE - MIN_SCALE) * (1 - Math.abs(position));
            view.setScaleX(scaleFactor);
            view.setScaleY(scaleFactor);
        } else {
            view.setAlpha(MIN_FADE);
        }
    }
}

You will also need to control the child drawing order to set the current selected View on top (only needed, if your views overlay each other):

public class MyPager extends ViewPager {
    public MyPager(Context context) {
        this(context, null);
    }

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

    @Override
    protected int getChildDrawingOrder(int childCount, int i) {
        if(i == childCount - 1) {
            return getCurrentItem();
        } else {
            return i >= getCurrentItem()? i + 1 : i;
        }
    }
}

Set ViewPager.setOffscreenPageLimit to 2 or even more, if you have more visible pages on screen.

Here is the result: