Question

我遇到了一个问题，我在ListView中有一个简单的BottomSheet，ListView有足够的项目来填充屏幕并滚动更多。

当我向下滚动时，一切似乎都有效，但是当我尝试向上滚动时，它正在滚动BottomSheet本身并关闭视图而不是仅滚动ListView。

一段时间后我找到了一个解决方案，因为我在这里找不到它，我想我会把它发布在这里。

Answer 1

解决方案是扩展ListView，如下所示：

public class BottomSheetListView extends ListView {
    public BottomSheetListView (Context context, AttributeSet p_attrs) {
        super (context, p_attrs);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        return true;
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        if (canScrollVertically(this)) {
            getParent().requestDisallowInterceptTouchEvent(true);
        }
        return super.onTouchEvent(ev);
    }

    public boolean canScrollVertically (AbsListView view) {
        boolean canScroll = false;

        if (view !=null && view.getChildCount ()> 0) {
            boolean isOnTop = view.getFirstVisiblePosition() != 0 || view.getChildAt(0).getTop() != 0;
            boolean isAllItemsVisible = isOnTop && view.getLastVisiblePosition() == view.getChildCount();

            if (isOnTop || isAllItemsVisible) {
                canScroll = true;
            }
        }

        return  canScroll;
    }
}

然后在您的布局文件bottom_sheet_view.xml中：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.mypackage.name.BottomSheetListView
        android:id="@+id/listViewBtmSheet"
        android:divider="@color/colorPrimary"
        android:dividerHeight="1dp"
        android:layout_weight="1"
        android:layout_width="match_parent"
        android:layout_height="0dp" />

</LinearLayout>

最后，在Activity / Fragment：

中

BottomSheetDialog dialog = new BottomSheetDialog(context);
dialog.setContentView(R.layout.bottom_sheet_view);

BottomSheetListView listView = (BottomSheetListView) dialog.findViewById(R.id.listViewBtmSheet);
// apply some adapter - add some data to listview

dialog.show();

这将提供BottomSheet完全使用ListView滚动。

Answer 2

如果您不想展开ListView，有更好的方法：

//in onCreate

_listView.setOnTouchListener(new ListView.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                int action = event.getAction();
                switch (action) {
                    case MotionEvent.ACTION_DOWN:
                        // Disallow NestedScrollView to intercept touch events.
                        v.getParent().requestDisallowInterceptTouchEvent(true);
                        break;

                    case MotionEvent.ACTION_UP:
                        // Allow NestedScrollView to intercept touch events.
                        v.getParent().requestDisallowInterceptTouchEvent(false);
                        break;
                }

                // Handle ListView touch events.
                v.onTouchEvent(event);
                return true;
            }
        });

Answer 3

public class BottomSheetListView extends ListView {

    public BottomSheetListView(Context context, AttributeSet attributeSet) {
        super(context, attributeSet);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent motionEvent) {
        View view = (View) getChildAt(getChildCount() - 1);

        int diffBottom = (view.getBottom() - (getHeight() + getScrollY()));
        if (motionEvent.getAction() == MotionEvent.ACTION_DOWN) {
            if (diffBottom == 0) {
                return false;
            }
        }

         /*//Need more improvement on this logic. Do not uncomment
        int diffTop = (view.getTop() - (getHeight() + getScrollY()));
        if (motionEvent.getAction() == MotionEvent.ACTION_DOWN) {
            if (diffTop < 0) {
                return true;
            }
        }*/

        return super.onInterceptTouchEvent(motionEvent);
    }

    @Override
    public boolean onTouchEvent(MotionEvent motionEvent) {
        if (canScrollVertically(this)) {
            getParent().requestDisallowInterceptTouchEvent(true);
        }
        return super.onTouchEvent(motionEvent);
    }

    public boolean canScrollVertically(AbsListView absListView) {

        boolean canScroll = false;

        if (absListView != null && absListView.getChildCount() > 0) {

            boolean isOnTop = absListView.getFirstVisiblePosition() != 0 || absListView.getChildAt(0).getTop() != 0;
            boolean isAllItemsVisible = isOnTop && getLastVisiblePosition() == absListView.getChildCount();

            if (isOnTop || isAllItemsVisible)
                canScroll = true;
        }

        return canScroll;
    }
}

Answer 4

这是具有触摸事件hadnling的正确列表视图自定义类

public class BottomSheetListView extends ListView
{
    public BottomSheetListView(Context context, AttributeSet p_attrs)
    {
        super(context, p_attrs);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev)
    {
        if (canScrollVertically(this))
        {
            getParent().requestDisallowInterceptTouchEvent(true);
        }
        return super.onInterceptTouchEvent(ev);
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev)
    {
        if (canScrollVertically(this))
        {
            getParent().requestDisallowInterceptTouchEvent(true);
        }
        return super.onTouchEvent(ev);
    }

    public boolean canScrollVertically(AbsListView view)
    {
        boolean canScroll = false;

        if (view != null && view.getChildCount() > 0)
        {
            boolean isOnTop = view.getFirstVisiblePosition() != 0 || view.getChildAt(0).getTop() != 0;
            boolean isAllItemsVisible = isOnTop && view.getLastVisiblePosition() == view.getChildCount();

            if (isOnTop || isAllItemsVisible)
            {
                canScroll = true;
            }
        }

        return canScroll;
    }
}

Answer 5

从版本22.1.0 开始，您可能想尝试setNestedScrollingEnabled=true

如果将此属性设置为true，则将允许该视图使用当前层次结构中的兼容父视图启动嵌套滚动操作。如果此视图未实现嵌套滚动，则将无效。在嵌套滚动进行过程中禁用嵌套滚动具有停止嵌套滚动的作用。

Reference to Google API

Answer 6

只需在您的内部将android:nestedScrollingEnabled设置为true 布局为ListView属性或listView.setNestedScrollingEnabled(true) 在Java中。

Answer 7

我知道这有点黑客但它对我有用，甚至listview也是可选择的。正如我们所知，当底部页面改变其状态时，它可以被捕获到它的监听器中，所以如果listview没有触及顶部则不要让它改变状态，因此触摸事件将被传递到listview并且将像它一样工作。 / p>

    mBottomSheetBehavior.setBottomSheetCallback(new BottomSheetBehavior.BottomSheetCallback(){
@Override
public void onStateChanged(View bottomSheet, int newState) {
        if (newState == BottomSheetBehavior.STATE_DRAGGING && !listIsAtTop()){
            mBottomSheetBehavior.setState(BottomSheetBehavior.STATE_EXPANDED);
        }
}
@Override
public void onSlide(View bottomSheet, float slideOffset) {}});

public boolean listIsAtTop()   {
    if(tripListView.getChildCount() == 0) return true;
    return (tripListView.getChildAt(0).getTop() == 0 && tripListView.getFirstVisiblePosition() ==0);
}

Answer 8

我尝试了此处介绍的嵌套ListView，但是在触摸ListView时，它们不允许展开/折叠底页。以下是我的解决方案，当您向上滚动而ListView无法向上滚动时，底页将被展开；当您向下滚动而ListView无法进行滚动时，BottomSheet将被折叠。

public class NestedListView extends ListView {

    private boolean mIsBeingDragged = false;
    private float mLastMotionY;

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

    public NestedListView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent event) {
        switch (event.getActionMasked()) {
            case MotionEvent.ACTION_DOWN: {
                if (canScrollDown() || canScrollUp()) {
                    final ViewParent parent = getParent();
                    if (parent != null) {
                        parent.requestDisallowInterceptTouchEvent(true);
                    }
                }
                break;
            }
        }
        return super.onInterceptTouchEvent(event);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        final float y = event.getRawY();

        switch (event.getActionMasked()) {
            case MotionEvent.ACTION_MOVE: {
                if (!mIsBeingDragged) {
                    final float deltaY = mLastMotionY - y;
                    mIsBeingDragged = (deltaY > 0 && canScrollDown())
                        || (deltaY < 0 && canScrollUp());

                    if (mIsBeingDragged) {
                        final ViewParent parent = getParent();
                        if (parent != null) {
                            parent.requestDisallowInterceptTouchEvent(true);
                        }
                    } else {
                        final ViewParent parent = getParent();
                        if (parent != null) {
                            parent.requestDisallowInterceptTouchEvent(false);
                        }
                        return false;
                    }
                }
            }

            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_CANCEL:
                mIsBeingDragged = false;
                break;
        }

        mLastMotionY = y;

        return super.onTouchEvent(event);
    }

    public boolean canScrollUp() {
        final int childCount = getChildCount();
        if (childCount == 0) {
            return false;
        }

        final int firstPosition = getFirstVisiblePosition();
        final int firstTop = getChildAt(0).getTop();
        return firstPosition > 0 || firstTop < getListPaddingTop();
    }

    public boolean canScrollDown() {
        final int childCount = getChildCount();
        if (childCount == 0) {
            return false;
        }

        final int firstPosition = getFirstVisiblePosition();
        final int lastBottom = getChildAt(childCount - 1).getBottom();
        final int lastPosition = firstPosition + childCount;
        return lastPosition < getCount() || lastBottom > getHeight() - getListPaddingBottom();
    }
}

BottomSheet中的ListView

8 个答案: