Android-ObservableScrollView - 使用 ViewPagerTabListViewFragment 时意外触摸会更改子 fragment

Question

我正在使用 Android-ObservableScrollView在我的项目中。我面临一个问题，即使我只是触摸 viewpager，SlidingTab 也会捕获此事件，并且 View 寻呼机的当前 fragment 会发生变化。我粘贴了我项目中的所有代码，但大部分代码与示例项目相似。

我在网上调查了这个问题，发现this issue有用，但我尝试了这个解决方案，但它对我不起作用。请帮忙。

THIS IS THE ISSUE

MainActivity.java

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_dash_board);
    mToolBar = (Toolbar) findViewById(R.id.toolbar);
    refreshJobsData = true;
    setUpViewPager();
}

public void setUpViewPager() {
    mHeaderView = findViewById(R.id.header);
    ViewCompat.setElevation(mHeaderView, getResources().getDimension(R.dimen.toolbar_elevation));
    mToolbarView = findViewById(R.id.toolbar);
    mPagerAdapter = new NavigationAdapter(getSupportFragmentManager());
    mPager = (ViewPager) findViewById(R.id.pager);
    mPager.setAdapter(mPagerAdapter);

    SlidingTabLayout slidingTabLayout = (SlidingTabLayout) findViewById(R.id.sliding_tabs);
    slidingTabLayout.setCustomTabView(R.layout.tab_indicator, android.R.id.text1);
    slidingTabLayout.setSelectedIndicatorColors(getResources().getColor(R.color.theme_green_dark));
    slidingTabLayout.setDistributeEvenly(false);
    slidingTabLayout.setViewPager(mPager);

    // When the page is selected, other fragments' scrollY should be adjusted
    // according to the toolbar status(shown/hidden)
    slidingTabLayout.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
        @Override
        public void onPageScrolled(int i, float v, int i2) {
        }

        @Override
        public void onPageSelected(int i) {
            propagateToolbarState(toolbarIsShown());
        }

        @Override
        public void onPageScrollStateChanged(int i) {
        }
    });

    propagateToolbarState(toolbarIsShown());
}

@Override
public void onScrollChanged(int scrollY, boolean firstScroll, boolean dragging) {
    if (dragging) {
        int toolbarHeight = mToolbarView.getHeight();
        float currentHeaderTranslationY = ViewHelper.getTranslationY(mHeaderView);
        if (firstScroll) {
            if (-toolbarHeight < currentHeaderTranslationY) {
                mBaseTranslationY = scrollY;
            }
        }
        float headerTranslationY = ScrollUtils.getFloat(-(scrollY - mBaseTranslationY), -toolbarHeight, 0);
        ViewPropertyAnimator.animate(mHeaderView).cancel();
        ViewHelper.setTranslationY(mHeaderView, headerTranslationY);
    }
}

@Override
public void onDownMotionEvent() {
}

@Override
public void onUpOrCancelMotionEvent(ScrollState scrollState) {
    mBaseTranslationY = 0;

    Fragment fragment = getCurrentFragment();
    if (fragment == null) {
        return;
    }
    View view = fragment.getView();
    if (view == null) {
        return;
    }

    int toolbarHeight = mToolbarView.getHeight();
    final ObservableListView listView = (ObservableListView) view.findViewById(R.id.scroll);
    if (listView == null) {
        return;
    }
    int scrollY = listView.getCurrentScrollY();
    if (scrollState == ScrollState.DOWN) {
        showToolbar();
    } else if (scrollState == ScrollState.UP) {
        if (toolbarHeight <= scrollY) {
            hideToolbar();
        } else {
            showToolbar();
        }
    } else {
        // Even if onScrollChanged occurs without scrollY changing, toolbar should be adjusted
        if (toolbarIsShown() || toolbarIsHidden()) {
            // Toolbar is completely moved, so just keep its state
            // and propagate it to other pages
            propagateToolbarState(toolbarIsShown());
        } else {
            // Toolbar is moving but doesn't know which to move:
            // you can change this to hideToolbar()
            showToolbar();
        }
    }
}

private Fragment getCurrentFragment() {
    return mPagerAdapter.getItemAt(mPager.getCurrentItem());
}

private void propagateToolbarState(boolean isShown) {
    int toolbarHeight = mToolbarView.getHeight();

    // Set scrollY for the fragments that are not created yet
    mPagerAdapter.setScrollY(isShown ? 0 : toolbarHeight);

    // Set scrollY for the active fragments
    for (int i = 0; i < mPagerAdapter.getCount(); i++) {
        // Skip current item
        if (i == mPager.getCurrentItem()) {
            continue;
        }

        // Skip destroyed or not created item
        Fragment f = mPagerAdapter.getItemAt(i);
        if (f == null) {
            continue;
        }

        ObservableListView listView = (ObservableListView) f.getView().findViewById(R.id.scroll);
        if (isShown) {
            // Scroll up
            if (0 < listView.getCurrentScrollY()) {
                listView.setSelection(0);
            }
        } else {
            // Scroll down (to hide padding)
            if (listView.getCurrentScrollY() < toolbarHeight) {
                listView.setSelection(1);
            }
        }
    }
}

private boolean toolbarIsShown() {
    return ViewHelper.getTranslationY(mHeaderView) == 0;
}

private boolean toolbarIsHidden() {
    return ViewHelper.getTranslationY(mHeaderView) == -mToolbarView.getHeight();
}

private void showToolbar() {
    float headerTranslationY = ViewHelper.getTranslationY(mHeaderView);
    if (headerTranslationY != 0) {
        ViewPropertyAnimator.animate(mHeaderView).cancel();
        ViewPropertyAnimator.animate(mHeaderView).translationY(0).setDuration(200).start();
    }
    propagateToolbarState(true);
}

private void hideToolbar() {
    float headerTranslationY = ViewHelper.getTranslationY(mHeaderView);
    int toolbarHeight = mToolbarView.getHeight();
    if (headerTranslationY != -toolbarHeight) {
        ViewPropertyAnimator.animate(mHeaderView).cancel();
        ViewPropertyAnimator.animate(mHeaderView).translationY(-toolbarHeight).setDuration(200).start();
    }
    propagateToolbarState(false);
}

private static class NavigationAdapter extends CacheFragmentStatePagerAdapter {

    private static final String[] TITLES = new String[]{"Applepie", "Butter Cookie", "Cupcake", "Donut", "Eclair", "Froyo", "Gingerbread", "Honeycomb", "Ice Cream Sandwich", "Jelly Bean", "KitKat", "Lollipop"};

    private int mScrollY;

    public NavigationAdapter(FragmentManager fm) {
        super(fm);
    }

    public void setScrollY(int scrollY) {
        mScrollY = scrollY;
    }

    @Override
    protected Fragment createItem(int position) {
        Fragment f = new ViewPagerTabListViewFragment();
        if (0 < mScrollY) {
            Bundle args = new Bundle();
            args.putInt(ViewPagerTabListViewFragment.ARG_INITIAL_POSITION, 1);
            f.setArguments(args);
        }
        return f;
    }

    @Override
    public int getCount() {
        return TITLES.length;
    }

    @Override
    public CharSequence getPageTitle(int position) {
        return TITLES[position];
    }
}

ViewPagerTabListViewFragment.java

公共(public)类 ViewPagerTabListViewFragment 扩展 fragment {

public static final String ARG_INITIAL_POSITION = "ARG_INITIAL_POSITION";

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_listview, container, false);

    Activity parentActivity = getActivity();
    final ObservableListView listView = (ObservableListView) view.findViewById(R.id.scroll);
    setDummyDataWithHeader(listView, inflater.inflate(R.layout.padding, null));

    if (parentActivity instanceof ObservableScrollViewCallbacks) {
        // Scroll to the specified position after layout
        Bundle args = getArguments();
        if (args != null && args.containsKey(ARG_INITIAL_POSITION)) {
            final int initialPosition = args.getInt(ARG_INITIAL_POSITION, 0);
            ScrollUtils.addOnGlobalLayoutListener(listView, new Runnable() {
                @Override
                public void run() {
                    // scrollTo() doesn't work, should use setSelection()
                    listView.setSelection(initialPosition);
                }
            });
        }
        listView.setScrollViewCallbacks((ObservableScrollViewCallbacks) parentActivity);
    }
    return view;
}

protected void setDummyDataWithHeader(ListView listView, View headerView) {
    listView.addHeaderView(headerView);
    final ArrayList<String> list = Utils.getDummyList();
    String[] array = list.toArray(new String[list.size()]);
    ArrayAdapter<String> adapter = new ArrayAdapter<>(getActivity(), android.R.layout.simple_list_item_1, array);
    listView.setAdapter(adapter);
    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            Utils.showToast(getActivity(), list.get(position).toUpperCase());
        }
    });
  }
}

MainActivity-Layout.xml

<!-- A DrawerLayout is intended to be used as the top-level content view using match_parent for both width and height to consume the full space available. -->

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <!--
Padding for ViewPager must be set outside the ViewPager itself
because with padding, EdgeEffect of ViewPager become strange.
-->
    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:paddingTop="48dp">

        <android.support.v4.view.ViewPager
            android:id="@+id/pager"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>
    </FrameLayout>

    <LinearLayout
        android:id="@+id/header"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="@color/theme_green_dark"
            android:minHeight="?attr/actionBarSize"
            app:popupTheme="@style/Theme.AppCompat.Light.DarkActionBar"
            app:theme="@style/Toolbar"
            android:elevation="4dp">
        </android.support.v7.widget.Toolbar>

        <!--<ImageView-->
            <!--android:layout_width="match_parent"-->
            <!--android:layout_height="@dimen/dimen_160_dp"-->
            <!--android:background="@color/loader_dark_color"/>-->

        <com.callathome.consumer.widgets.SlidingTabLayout
            android:id="@+id/sliding_tabs"
            android:layout_width="match_parent"
            android:layout_height="@dimen/tab_height"
            android:background="@color/white"/>
    </LinearLayout>
</FrameLayout>

<fragment
    android:id="@+id/navigation_drawer"
    android:layout_width="@dimen/navigation_drawer_width"
    android:layout_height="match_parent"
    android:layout_gravity="start"
    android:name="com.callathome.consumer.fragment.NavigationDrawerFragment"
    tools:layout="@layout/fragment_navigation_drawer"/>

请帮忙!

提前致谢。

Answer 1

看来是 ObservableListView 内部的问题。
为了拦截触摸事件，ObservableListView 被设计为调用其父级的 onInterceptTouchEvent() 并且父级 - 在本例中，父级是 ViewPager - 意外地处理了触摸事件，这导致了这种行为。

无论如何，我找到了解决方法。
您可以在您的应用中试试这个吗？

1. 添加一个 ID 到根 ViewGroup在你的 MainActivity-Layout.xml 中，比如 android:id="@+id/root":

   <FrameLayout
       android:id="@+id/root"
       android:layout_width="match_parent"
       android:layout_height="match_parent">
   
       <!--
       Padding for ViewPager must be set outside the ViewPager itself
       because with padding, EdgeEffect of ViewPager become strange.
       -->
   

2. 然后将这个FrameLayout设置为TouchInterceptionViewGroup到 ViewPagerTabListViewFragment.java 中的 ObservableListView。也许围绕 listView.setScrollViewCallbacks() 是好的。

   listView.setTouchInterceptionViewGroup((ViewGroup) parentActivity.findViewById(R.id.root));
   listView.setScrollViewCallbacks((ObservableScrollViewCallbacks) parentActivity);