使用view pager android覆盖Flow功能

Question

我必须在我的应用程序中实现类似的封面流程功能 mobikwik app cover flow

和。

我已经尝试了Android CoverFlow widget library和其他几个人。但没有任何工作按预期。

如何使用ViewPager实现此类视图？

Answer 1

我创建了我的课程ZoomOutPageTransformer，该课程正在实施PageTransformer，并使用setPageTransformer()方法将其设置到寻呼机中。 请检查ZoomOutPageTransformer.class -

public class ZoomOutPageTransformer implements PageTransformer {
    private static float MIN_SCALE = 1f;
    private static final float MIN_ALPHA = 0.7f;


    public ZoomOutPageTransformer(boolean isZoomEnable) {
        if (isZoomEnable) {
            MIN_SCALE = 0.85f;
        } else {
            MIN_SCALE = 1f;
        }
    }

    public void transformPage(View view, float position) {
        int pageWidth = view.getWidth();
        int pageHeight = view.getHeight();
        float vertMargin = pageHeight * (1 - MIN_SCALE) / 2;
        float horzMargin = pageWidth * (1 - MIN_SCALE) / 2;
        view.setScaleX(MIN_SCALE);
        view.setScaleY(MIN_SCALE);
        if (position < -1) { // [-Infinity,-1)
            // This page is way off-screen to the left.
            view.setAlpha(MIN_ALPHA);
            view.setTranslationX(horzMargin - vertMargin / 2);


        } else if (position <= 1) { // [-1,1]
            // Modify the default slide transition to shrink the page as well
            float scaleFactor = Math.max(MIN_SCALE, 1 - Math.abs(position));
            vertMargin = pageHeight * (1 - scaleFactor) / 2;
            horzMargin = pageWidth * (1 - scaleFactor) / 2;
            if (position < 0) {
                view.setTranslationX(horzMargin - vertMargin / 2);
            } else {
                view.setTranslationX(-horzMargin + vertMargin / 2);
            }

            // Scale the page down (between MIN_SCALE and 1)
            view.setScaleX(scaleFactor);
            view.setScaleY(scaleFactor);

            // Fade the page relative to its size.
            view.setAlpha(MIN_ALPHA +
                    (scaleFactor - MIN_SCALE) /
                            (1 - MIN_SCALE) * (1 - MIN_ALPHA));

        } else { // (1,+Infinity]
            // This page is way off-screen to the right.
            view.setAlpha(MIN_ALPHA);
            view.setTranslationX(-horzMargin + vertMargin / 2);

        }
    }
}

并在PagerActivity.java -

public class PagerActivity extends Activity {

    ViewPager pager;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        pager = (ViewPager) findViewById(R.id.viewPager);
//        mContainer.setViewPager(pager);
        PagerAdapter adapter = new MyPagerAdapter();
        pager.setPageTransformer(true, new ZoomOutPageTransformer(true));
        pager.setAdapter(adapter);
        //Necessary or the pager will only have one extra page to show
        // make this at least however many pages you can see
//        pager.setOffscreenPageLimit(adapter.getCount());
        pager.setOffscreenPageLimit(3);
        //A little space between pages
        pager.setPageMargin((int) getResources().getDimension(R.dimen.dimen_20));
        //If hardware acceleration is enabled, you should also remove
        // clipping on the pager for its children.
        pager.setClipChildren(false);
    }
    //Nothing special about this adapter, just throwing up colored views for demo
    private class MyPagerAdapter extends PagerAdapter {
        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            TextView view = new TextView(PagerActivity.this);
            view.setText("Item " + position);
            view.setGravity(Gravity.CENTER);
            view.setBackgroundColor(Color.argb(255, position * 50, position * 10, position * 50));
            container.addView(view);
            return view;
        }
        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            container.removeView((View) object);
        }
        @Override
        public int getCount() {
            return 9;
        }
        @Override
        public boolean isViewFromObject(View view, Object object) {
            return (view == object);
        }
    }
}

<{1>} -

中的

main.xml

它对我有用。