Question

RecyclerView嵌套在CardView中。我尝试致电addItemDecoration()将分频器添加到RecycylerView，但它没有用。

<android.support.v7.widget.CardView xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    card_view:cardBackgroundColor="@color/white_color"
    android:layout_marginLeft="10dp"
    android:layout_marginRight="10dp"
    card_view:cardElevation="3dp">

    <android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/swipe_saleproduct_list"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <android.support.v7.widget.RecyclerView
            android:id="@+id/recycler_saleproduct_list"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_centerHorizontal="true"
            android:layout_centerVertical="true"
            android:visibility="visible" />

    </android.support.v4.widget.SwipeRefreshLayout>
</android.support.v7.widget.CardView>

java代码：

    mSwipe = (SwipeRefreshLayout)view.findViewById(R.id.swipe_saleproduct_list);
    mRecyclerView= (RecyclerView) view.findViewById(R.id.recycler_saleproduct_list);
    mRecyclerView.setLayoutManager(new LinearLayoutManager(UIUtils.getContext()));
    mRecyclerView.addItemDecoration(new DividerItemDecoration(UIUtils.getContext(), DividerItemDecoration.VERTICAL_LIST));
    SaleProductListAdapter saleProductListAdapter = new SaleProductListAdapter(UIUtils.getContext(), mRecyclerView, list, mSwipe);
    mRecyclerView.setAdapter(saleProductListAdapter);

Answer 1

以下是一个很好的例子，请看一下：

<head>

这是我的public class DividerItemDecoration extends RecyclerView.ItemDecoration { private static final int[] ATTRS = new int[]{ android.R.attr.listDivider }; public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL; public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL; private Drawable mDivider; private int mOrientation; public DividerItemDecoration(Context context, int orientation) { final TypedArray a = context.obtainStyledAttributes(ATTRS); mDivider = a.getDrawable(0); a.recycle(); setOrientation(orientation); } public void setOrientation(int orientation) { if (orientation != HORIZONTAL_LIST && orientation != VERTICAL_LIST) { throw new IllegalArgumentException("invalid orientation"); } mOrientation = orientation; } @Override public void onDraw(Canvas c, RecyclerView parent) { if (mOrientation == VERTICAL_LIST) { drawVertical(c, parent); } else { drawHorizontal(c, parent); } } public void drawVertical(Canvas c, RecyclerView parent) { final int left = parent.getPaddingLeft(); final int right = parent.getWidth() - parent.getPaddingRight(); final int childCount = parent.getChildCount(); for (int i = 0; i < childCount; i++) { final View child = parent.getChildAt(i); final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child .getLayoutParams(); final int top = child.getBottom() + params.bottomMargin; final int bottom = top + mDivider.getIntrinsicHeight(); mDivider.setBounds(left, top, right, bottom); mDivider.draw(c); } } public void drawHorizontal(Canvas c, RecyclerView parent) { final int top = parent.getPaddingTop(); final int bottom = parent.getHeight() - parent.getPaddingBottom(); final int childCount = parent.getChildCount(); for (int i = 0; i < childCount; i++) { final View child = parent.getChildAt(i); final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child .getLayoutParams(); final int left = child.getRight() + params.rightMargin; final int right = left + mDivider.getIntrinsicHeight(); mDivider.setBounds(left, top, right, bottom); mDivider.draw(c); } } @Override public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) { if (mOrientation == VERTICAL_LIST) { outRect.set(0, 0, 0, mDivider.getIntrinsicHeight()); } else { outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0); } } }，它运作良好，Fragment清晰而薄：

divider

我希望你会受到启发。

Answer 2

平台KitKat及以下版本的mDivider系统可能NullPointerException，因此我建议您自己使用mDivider：

 public MyDecoration(Context context, int orientation) {
    mDivider = context.getResources().getDrawable(R.drawable.line_divider);
    setOrientation(orientation);
 }

以下是line_divider：

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<size
    android:width="1dp"
    android:height="1dp" />
<solid android:color="@color/color_in_common_green" />
</shape>

它可能运作良好

调用addItemDecoration（）后，分隔符在RecyclerView中没有显示

2 个答案: