Question

我在我的新项目中使用Android-ParallaxHeaderViewPager。它在片段内使用listview完美地工作，但是当我使用scrollview时它不起作用（标题得到修复，并且与listview片段的效果不同）。任何帮助，将不胜感激。这是我的代码：

fragment_lore.xml （不工作）

<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/scrollViewLore">
        <TextView
            android:id="@+id/championLore"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>
</ScrollView>

LoreFragment.java

public class LoreFragment extends ScrollTabHolderFragment implements OnScrollListener {

    private int mPosition;
    private ScrollView mScrollView;
    private int mTabBarHeight;
    private int mTopImageHeight;

    public static final LoreFragment newInstance(Integer position, Integer pos){
        LoreFragment fragment = new LoreFragment();
        Bundle args = new Bundle();
        args.putInt("position",position);
        args.putInt("pos",pos);
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mPosition = getArguments().getInt("position");

    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_lore,container,false);
        mScrollView = (ScrollView) view.findViewById(R.id.scrollViewLore);
        mTabBarHeight = getResources().getDimensionPixelSize(R.dimen.tab_bar_height);
        KenBurnsView headerImg = (KenBurnsView) getActivity().findViewById(R.id.header_picture);
        mTopImageHeight = headerImg.getHeight();
        TextView loreView = (TextView) view.findViewById(R.id.championLore);
        Integer pos = Integer.valueOf(getArguments().getInt("pos"));
        String lore = Cache.champions.get(pos).getDescription();
        lore = lore.replace("<br>","\n");
        loreView.setText(lore);
        return view;
    }

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);

    }

    @Override
    public void adjustScroll(int scrollHeight) {
        if (scrollHeight == 0 && mScrollView.getScrollY() > mTopImageHeight - mTabBarHeight) {
            // ScrollView does not need to adjust scroll, as the tab bar is its sticky position
            return;
        }
        mScrollView.scrollTo(mScrollView.getScrollX(), -scrollHeight + mTopImageHeight - mTabBarHeight);
    }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
        if (mScrollTabHolder != null)
            mScrollTabHolder.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount, mPosition);
    }

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        // nothing
    }
}

MainActivity.java

public class ChampionDetailsActivity extends ActionBarActivity implements ScrollTabHolder, ViewPager.OnPageChangeListener{
...
@Override
    public void onPageScrollStateChanged(int arg0) {
        // nothing
    }

    @Override
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
        // nothing
    }

    @Override
    public void onPageSelected(int position) {
        SparseArrayCompat<ScrollTabHolder> scrollTabHolders = mPagerAdapter.getScrollTabHolders();
        ScrollTabHolder currentHolder = scrollTabHolders.valueAt(position);

        currentHolder.adjustScroll((int) (mHeader.getHeight() + mHeader.getTranslationY()));
    }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount, int pagePosition) {
        if (mViewPager.getCurrentItem() == pagePosition) {
            int scrollY = getScrollY(view);
            mHeader.setTranslationY(Math.max(-scrollY, mMinHeaderTranslation));
            float ratio = clamp(mHeader.getTranslationY() / mMinHeaderTranslation, 0.0f, 1.0f);
            setTitleAlpha(clamp(5.0F * ratio - 4.0F, 0.0F, 1.0F));
        }
    }

    @Override
    public void adjustScroll(int scrollHeight) {
        // nothing
    }

    public int getScrollY(AbsListView view) {
        View c = view.getChildAt(0);
        if (c == null) {
            return 0;
        }

        int firstVisiblePosition = view.getFirstVisiblePosition();
        int top = c.getTop();

        int headerHeight = 0;
        if (firstVisiblePosition >= 1) {
            headerHeight = mHeaderHeight;
        }

        return -top + firstVisiblePosition * c.getHeight() + headerHeight;
    }

    public static float clamp(float value, float max, float min) {
        return Math.max(Math.min(value, min), max);
    }

public int getActionBarHeight() {
        if (mActionBarHeight != 0) {
            return mActionBarHeight;
        }
        getTheme().resolveAttribute(android.R.attr.actionBarSize, mTypedValue, true);
        mActionBarHeight = TypedValue.complexToDimensionPixelSize(mTypedValue.data, getResources().getDisplayMetrics());
        return mActionBarHeight;
    }
...
public class PagerAdapter extends FragmentPagerAdapter {

        private Integer pos;
        private ScrollTabHolder mListener;
        private SparseArrayCompat<ScrollTabHolder> mScrollTabHolders;
        ...

        public PagerAdapter(FragmentManager fm) {
            super(fm);
            mScrollTabHolders = new SparseArrayCompat<ScrollTabHolder>();
        }

        public PagerAdapter(FragmentManager fm, Integer pos) {
            super(fm);
            this.pos=pos;
            mScrollTabHolders = new SparseArrayCompat<ScrollTabHolder>();

        }

        public void setTabHolderScrollingContent(ScrollTabHolder listener) {
            mListener = listener;
        }

...

        @Override
        public Fragment getItem(int position) {

            ScrollTabHolderFragment fragment = null;
            switch (position) {
                case 0:
                    fragment = (ScrollTabHolderFragment) ListViewFragment.newInstance(position,pos);
                    break;
                case 1:
                    fragment = (ScrollTabHolderFragment) LoreFragment.newInstance(position,pos);
                    break;
            }

            mScrollTabHolders.put(position, fragment);
            if (mListener != null) {
                fragment.setScrollTabHolder(mListener);
            }

            return fragment;
        }

        public SparseArrayCompat<ScrollTabHolder> getScrollTabHolders() {
            return mScrollTabHolders;
        }

另外，我尝试that article，但无法修复我的滚动视图。如果您需要更多代码，请告诉我。

提前致谢。

Answer 1

我也想了解如何设置相对于标题图像的scrollView高度！我猜你试图实现这里显示的内容 - http://nerds.airbnb.com/host-experience-android/

Answer 2

您最好查看此http://flavienlaurent.com/blog/2013/11/20/making-your-action-bar-not-boring/链接以了解您的程序，因为ParallaxHeaderViewPager是使用本文完成的。希望这会帮助你。

Answer 3

我用scrollview而不是listview编写了一个demo，并使用fragment作为容器视图而不是activity。

Android-ParallaxHeaderViewPager_ScrollView

也许你迟到了，但我希望它对别人有用......

ScrollView中的Android ParallaxHeaderViewPager无法正常工作

3 个答案: