2016年10月更新

在v25.0.0支持库中，终于有了基本水平和垂直分隔符的默认实现!

DividerItemDecoration

我在列表中添加了一行，如下所示:

<View
    android:id="@+id/divider"
    android:layout_width="match_parent"
    android:layout_height="1px"
    android:background="@color/dividerColor"/>

1px会画出细线。

如果你想隐藏最后一行的分隔符，那么使用separator . setvisibility (View.GONE);onBindViewHolder的最后一个列表项。

为视图添加边距。这对我很管用。

android:layout_marginTop="10dp"

如果你只是想在XML中添加相等的间距，只需在RecyclerView中设置padding，并在你膨胀到RecyclerView中的项目中设置等量的layoutMargin，并让背景颜色决定间距颜色。

我有一个非常简单的方法在RecyclerView中添加一个分隔符。使用自定义适配器修改回收器视图布局，然后与回收器视图项目一起添加带有背景色(将是分隔色)的线性布局，并添加1dp的高度(或根据您的要求)和宽度以匹配父级。

下面是一个示例代码。

<?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">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:padding="18dp">

        <TextView
            android:id="@+id/list_row_SNO"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight=".8"
            android:layout_gravity="end"
            android:text="44."
            android:textAlignment="center"
            android:textSize="24sp"
            android:textColor="@color/colorBlack"
            android:fontFamily="sans-serif-condensed" />

        <TextView
            android:id="@+id/list_row_Heading"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight=".2"
            android:layout_gravity="start"
            android:text="Student's application for leave and this what"
            android:textAlignment="textStart"
            android:textSize="24sp"
            android:textColor="@color/colorBlack"
            android:fontFamily="sans-serif-condensed" />

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="@color/colorHighlight">
    </LinearLayout>

</LinearLayout>

只需在回收器视图对象的init之后添加这一行。

在片段:

mRecyclerView.addItemDecoration(new DividerItemDecoration(getActivity(),android.R.drawable.divider_horizontal_bright));

在活动

mRecyclerView.addItemDecoration(new DividerItemDecoration(this,android.R.drawable.divider_horizontal_bright));

项目装饰

public class DividerItemDecoration extends RecyclerView.ItemDecoration {
    public static final int VERTICAL_LIST = 0;

    public DividerItemDecoration(ListActivity listActivity, Object p1) {
    }

    private static final int[] ATTRS = new int[]{android.R.attr.listDivider};

    private Drawable mDivider;

    /**
     * Default divider will be used
     */
    public DividerItemDecoration(Context context) {
        final TypedArray styledAttributes = context.obtainStyledAttributes(ATTRS);
        mDivider = styledAttributes.getDrawable(0);
        styledAttributes.recycle();
    }

    /**
     * Custom divider will be used
     */
    public DividerItemDecoration(Context context, int resId) {
        mDivider = ContextCompat.getDrawable(context, resId);
    }

    @Override
    public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
        int left = parent.getPaddingLeft();
        int right = parent.getWidth() - parent.getPaddingRight();

        int childCount = parent.getChildCount();
        for (int i = 0; i < childCount; i++) {
            View child = parent.getChildAt(i);

            RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();

            int top = child.getBottom() + params.bottomMargin;
            int bottom = top + mDivider.getIntrinsicHeight();

            mDivider.setBounds(left, top, right, bottom);
            mDivider.draw(c);
        }
    }
}

一个简单的ItemDecoration实现，所有项目之间的空间相等:

public class SpacesItemDecoration extends RecyclerView.ItemDecoration {
    private int space;

    public SpacesItemDecoration(int space) {
        this.space = space;
    }

    @Override
    public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
        outRect.left = space;
        outRect.right = space;
        outRect.bottom = space;

        // Add top margin only for the first item to avoid double space between items
        if(parent.getChildAdapterPosition(view) == 0) {
            outRect.top = space;
        }
    }
}