我有一个android布局,其中有一个带有许多元素的scrollView。在scrollView的底部,我有一个listView,然后由适配器填充。

我遇到的问题是,android是排除listView从scrollView作为scrollView已经有一个可滚动的功能。我希望listView和内容一样长,并且主滚动视图是可滚动的。

我怎样才能实现这种行为呢?

这是我的主要布局:

<ScrollView
    android:id="@+id/scrollView1"
    android:layout_width="match_parent"
    android:layout_height="0dp"
    android:layout_weight="2"
    android:fillViewport="true"
    android:gravity="top" >

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

</ScrollView>

然后,我以编程方式将我的组件添加到linearlayour的id: foodItemActvity_linearLayout_fragments。下面是加载到线性布局中的一个视图。就是这个给我的卷轴带来了麻烦。

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

    <TextView
       android:id="@+id/fragment_dds_review_textView_label"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:text="Reviews:"
       android:textAppearance="?android:attr/textAppearanceMedium" />

   <ListView
       android:id="@+id/fragment_dds_review_listView"
       android:layout_width="match_parent"
       android:layout_height="wrap_content">
   </ListView>
</LinearLayout>

我的适配器然后填充这个列表视图。

当我点击主scrollView时,这是一个来自android层级查看器的图像:

如您所见,它排除了评论列表视图。

我应该能够向下滚动页面,看到8个评论,但它只显示了这3个,我可以滚动评论所在的一小部分。我想要一个全局页面滚动


当前回答

在xml:

<com.example.util.NestedListView
                    android:layout_marginTop="10dp"
                    android:id="@+id/listview"
                    android:layout_width="fill_parent"
                    android:layout_height="fill_parent"
                    android:divider="@null"

                    android:layout_below="@+id/rl_delivery_type" >
                </com.example.util.NestedListView>

在Java中:

public class NestedListView extends ListView implements View.OnTouchListener, AbsListView.OnScrollListener {

    private int listViewTouchAction;
    private static final int MAXIMUM_LIST_ITEMS_VIEWABLE = 99;

    public NestedListView(Context context, AttributeSet attrs) {
        super(context, attrs);
        listViewTouchAction = -1;
        setOnScrollListener(this);
        setOnTouchListener(this);
    }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem,
                         int visibleItemCount, int totalItemCount) {
        if (getAdapter() != null && getAdapter().getCount() > MAXIMUM_LIST_ITEMS_VIEWABLE) {
            if (listViewTouchAction == MotionEvent.ACTION_MOVE) {
                scrollBy(0, -1);
            }
        }
    }

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        int newHeight = 0;
        final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
        int heightSize = MeasureSpec.getSize(heightMeasureSpec);
        if (heightMode != MeasureSpec.EXACTLY) {
            ListAdapter listAdapter = getAdapter();
            if (listAdapter != null && !listAdapter.isEmpty()) {
                int listPosition = 0;
                for (listPosition = 0; listPosition < listAdapter.getCount()
                        && listPosition < MAXIMUM_LIST_ITEMS_VIEWABLE; listPosition++) {
                    View listItem = listAdapter.getView(listPosition, null, this);
                    //now it will not throw a NPE if listItem is a ViewGroup instance
                    if (listItem instanceof ViewGroup) {
                        listItem.setLayoutParams(new LayoutParams(
                                LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
                    }
                    listItem.measure(widthMeasureSpec, heightMeasureSpec);
                    newHeight += listItem.getMeasuredHeight();
                }
                newHeight += getDividerHeight() * listPosition;
            }
            if ((heightMode == MeasureSpec.AT_MOST) && (newHeight > heightSize)) {
                if (newHeight > heightSize) {
                    newHeight = heightSize;
                }
            }
        } else {
            newHeight = getMeasuredHeight();
        }
        setMeasuredDimension(getMeasuredWidth(), newHeight);
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        if (getAdapter() != null && getAdapter().getCount() > MAXIMUM_LIST_ITEMS_VIEWABLE) {
            if (listViewTouchAction == MotionEvent.ACTION_MOVE) {
                scrollBy(0, 1);
            }
        }
        return false;
    }
}

其他回答

你可以通过添加android:fillViewport="true"到你的ScrollView解决这个问题。

<ScrollView
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:background="@color/white"
      android:fillViewport="true"
      android:scrollbars="vertical">

<ListView
      android:id="@+id/statusList"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:animationCache="false"
      android:divider="@null"
      android:scrollingCache="false"
      android:smoothScrollbar="true" />

</ScrollView>

在使用该属性之前,列表视图中只有一个子视图是可见的。使用后,list的所有行或子元素都是可见的。

对于任何子视图在ScrollView内滚动。ListView, RecyclerView,等等。你只需要用androidx.core.widget.NestedScrollView替换当前xml中的ScrollView,然后奇迹就发生了。

下面是一个示例xml代码:

<?xml version="1.0" encoding="utf-8"?>
<androidx.core.widget.NestedScrollView
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <androidx.appcompat.widget.LinearLayoutCompat
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:padding="16dp"
        android:paddingBottom="20dp">

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Recycler View inside a Scroll View"
            android:textColor="@color/black"
            android:textSize="@dimen/_20sp"
            android:textStyle="bold" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="8dp"
            android:text="Below is a Recycler View as an example."
            android:textSize="16sp" />

        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/recycler_view"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="8dp"
            app:layout_constraintTop_toBottomOf="@id/et_damaged_qty" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="8dp"
            android:text="This textview automatically goes below the Recycler View."
            android:textSize="16sp" />
    </androidx.appcompat.widget.LinearLayoutCompat>
</androidx.core.widget.NestedScrollView>

现在你可以摆脱所有丑陋的黑客,你做了围绕嵌套滚动。

listView.setOnTouchListener(new View.OnTouchListener() {

@Override
public boolean onTouch(View v, MotionEvent event) {
    scrollView.requestDisallowInterceptTouchEvent(true);

    int action = event.getActionMasked();

    switch (action) {
        case MotionEvent.ACTION_UP:
            scrollView.requestDisallowInterceptTouchEvent(false);
            break;
    }

    return false;
}
});

如果你只是在代码中实现了一个ListView,这段代码将解决你的问题。

如果你使用RelativeLayout作为ListView子视图,那么这段代码将返回一个NullPointerException。测量(0,0);,因为相对布局。解决办法是把Relativelayout放在LinearLayout里面,它会工作得很好。

public static void setListViewHeightBasedOnChildren(ListView listView) {
    ListAdapter listAdapter = listView.getAdapter(); 
    if (listAdapter == null) {
        // pre-condition
        return;
    }

    int totalHeight = 0;
    for (int i = 0; i < listAdapter.getCount(); i++) {
        View listItem = listAdapter.getView(i, null, listView);
        listItem.measure(0, 0);
        totalHeight += listItem.getMeasuredHeight();
    }

    ViewGroup.LayoutParams params = listView.getLayoutParams();
    params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
    listView.setLayoutParams(params);
    listView.requestLayout();
}

在xml:

<com.example.util.NestedListView
                    android:layout_marginTop="10dp"
                    android:id="@+id/listview"
                    android:layout_width="fill_parent"
                    android:layout_height="fill_parent"
                    android:divider="@null"

                    android:layout_below="@+id/rl_delivery_type" >
                </com.example.util.NestedListView>

在Java中:

public class NestedListView extends ListView implements View.OnTouchListener, AbsListView.OnScrollListener {

    private int listViewTouchAction;
    private static final int MAXIMUM_LIST_ITEMS_VIEWABLE = 99;

    public NestedListView(Context context, AttributeSet attrs) {
        super(context, attrs);
        listViewTouchAction = -1;
        setOnScrollListener(this);
        setOnTouchListener(this);
    }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem,
                         int visibleItemCount, int totalItemCount) {
        if (getAdapter() != null && getAdapter().getCount() > MAXIMUM_LIST_ITEMS_VIEWABLE) {
            if (listViewTouchAction == MotionEvent.ACTION_MOVE) {
                scrollBy(0, -1);
            }
        }
    }

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        int newHeight = 0;
        final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
        int heightSize = MeasureSpec.getSize(heightMeasureSpec);
        if (heightMode != MeasureSpec.EXACTLY) {
            ListAdapter listAdapter = getAdapter();
            if (listAdapter != null && !listAdapter.isEmpty()) {
                int listPosition = 0;
                for (listPosition = 0; listPosition < listAdapter.getCount()
                        && listPosition < MAXIMUM_LIST_ITEMS_VIEWABLE; listPosition++) {
                    View listItem = listAdapter.getView(listPosition, null, this);
                    //now it will not throw a NPE if listItem is a ViewGroup instance
                    if (listItem instanceof ViewGroup) {
                        listItem.setLayoutParams(new LayoutParams(
                                LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
                    }
                    listItem.measure(widthMeasureSpec, heightMeasureSpec);
                    newHeight += listItem.getMeasuredHeight();
                }
                newHeight += getDividerHeight() * listPosition;
            }
            if ((heightMode == MeasureSpec.AT_MOST) && (newHeight > heightSize)) {
                if (newHeight > heightSize) {
                    newHeight = heightSize;
                }
            }
        } else {
            newHeight = getMeasuredHeight();
        }
        setMeasuredDimension(getMeasuredWidth(), newHeight);
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        if (getAdapter() != null && getAdapter().getCount() > MAXIMUM_LIST_ITEMS_VIEWABLE) {
            if (listViewTouchAction == MotionEvent.ACTION_MOVE) {
                scrollBy(0, 1);
            }
        }
        return false;
    }
}