我有一个非常简单的RecyclerView。这就是我设置分隔符的方法
DividerItemDecoration itemDecorator = new DividerItemDecoration(getContext(), DividerItemDecoration.VERTICAL);
itemDecorator.setDrawable(ContextCompat.getDrawable(getActivity(), R.drawable.news_divider));
recyclerView.addItemDecoration(itemDecorator);
这是drawable / news_divider.xml
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
<solid android:color="@color/white_two"/>
<size android:height="1dp"/>
</shape>
问题是由于某些愚蠢的原因，分隔符不仅仅是在项目之间创建的。但也是在最后一项之后。而且我只想在每个项目之后的项目之间。
知道如何防止分隔符在最后一项之后显示吗？
干杯谢谢
试试这个代码，它不会显示最后一项的分隔符。
public class DividerItemDecorator extends RecyclerView.ItemDecoration {
private Drawable mDivider;
public DividerItemDecorator(Drawable divider) {
mDivider = divider;
}
@Override
public void onDraw(Canvas canvas, RecyclerView parent, RecyclerView.State state) {
int dividerLeft = parent.getPaddingLeft();
int dividerRight = parent.getWidth() - parent.getPaddingRight();
int childCount = parent.getChildCount();
for (int i = 0; i <= childCount - 2; i++) {
View child = parent.getChildAt(i);
RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
int dividerTop = child.getBottom() + params.bottomMargin;
int dividerBottom = dividerTop + mDivider.getIntrinsicHeight();
mDivider.setBounds(dividerLeft, dividerTop, dividerRight, dividerBottom);
mDivider.draw(canvas);
}
}
}
divider.xml：
<?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/grey_300" />
</shape>
像这样设置你的分频器：
RecyclerView.ItemDecoration dividerItemDecoration = new DividerItemDecorator(ContextCompat.getDrawable(context, R.drawable.divider));
recyclerView.addItemDecoration(dividerItemDecoration);
正如提议的here，您可以像这样扩展DividerItemDecoration：
recyclerView.addItemDecoration(
new DividerItemDecoration(context, linearLayoutManager.getOrientation()) {
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
int position = parent.getChildAdapterPosition(view);
// hide the divider for the last child
if (position == parent.getAdapter().getItemCount() - 1) {
outRect.setEmpty();
} else {
super.getItemOffsets(outRect, view, parent, state);
}
}
}
);
[UPDATE] @Rebecca Hsieh指出：
这在RecyclerView中的项目视图没有透明背景时有效，例如，
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:background="#ffffff">
...
</LinearLayout>
RecyclerView调用DividerItemDecoration.getItemOffsets来测量子位置。此解决方案将最后一个分隔符放在最后一个项目后面。因此，RecyclerView中的项目视图应该有一个背景来覆盖最后一个分隔符，这使它看起来像隐藏。
其他方案
如果你不喜欢后面的分割器，你可以简单地复制或扩展DividerItemDecoration类并通过修改for (int i = 0; i < childCount; i++)到for (int i = 0; i < childCount - 1; i++)来改变它的绘制行为
接受的答案不会为装饰分配空间，因为它不会覆盖getItemOffsets()
我从支持库调整了DividerItemDecoration，以排除最后一项的装饰
public class DividerItemDecorator extends RecyclerView.ItemDecoration {
private Drawable mDivider;
private final Rect mBounds = new Rect();
public DividerItemDecorator(Drawable divider) {
mDivider = divider;
}
@Override
public void onDraw(Canvas canvas, RecyclerView parent, RecyclerView.State state) {
canvas.save();
final int left;
final int right;
if (parent.getClipToPadding()) {
left = parent.getPaddingLeft();
right = parent.getWidth() - parent.getPaddingRight();
canvas.clipRect(left, parent.getPaddingTop(), right,
parent.getHeight() - parent.getPaddingBottom());
} else {
left = 0;
right = parent.getWidth();
}
final int childCount = parent.getChildCount();
for (int i = 0; i < childCount - 1; i++) {
final View child = parent.getChildAt(i);
parent.getDecoratedBoundsWithMargins(child, mBounds);
final int bottom = mBounds.bottom + Math.round(child.getTranslationY());
final int top = bottom - mDivider.getIntrinsicHeight();
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(canvas);
}
canvas.restore();
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
if (parent.getChildAdapterPosition(view) == state.getItemCount() - 1) {
outRect.setEmpty();
} else
outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());
}
}
要应用装饰器，请使用
RecyclerView.ItemDecoration dividerItemDecoration = new DividerItemDecorator(dividerDrawable);
recyclerView.addItemDecoration(dividerItemDecoration);
包括方向的来源可以在这里找到https://gist.github.com/abdulalin/146f8ca42aa8322692b15663b8d508ff
这是我在我的应用程序中使用的DividerDecorator类，它删除了最后一项的底线。
public class DividerDecorator extends RecyclerView.ItemDecoration {
private Drawable mDivider;
public DividerDecorator(Context context) {
mDivider = context.getResources().getDrawable(R.drawable.recyclerview_divider);
}
@Override
public void onDrawOver(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);
}
}
}
您可以使用以下代码将其设置为RecyclerView：
mRecyclerViewEvent.addItemDecoration(new DividerDecorator(context));
这是recyclerview_divider.xml
<size
android:width="1dp"
android:height="1dp" />
<solid android:color="@color/DividerColor" />
创建自己的Divider类（Example here）
在绘制分隔符的代码中，首先检查是否为列表中的最后一项绘制分隔符。如果是这样，请不要画它。
请注意，如果你覆盖OnDrawOver，它会在您的视图的顶部绘制，包括滚动条等。最好坚持使用OnDraw。很多关于Google的例子，但this是一个关于创建自己的装饰器的好教程。
这是Android支持DividerItemDecoration的自定义版本，忽略了最后一项：
https://gist.github.com/mohsenoid/8ffdfa53f0465533833b0b44257aa641
主要区别是：
private fun drawVertical(canvas: Canvas, parent: RecyclerView) {
canvas.save()
val left: Int
val right: Int
if (parent.clipToPadding) {
left = parent.paddingLeft
right = parent.width - parent.paddingRight
canvas.clipRect(left, parent.paddingTop, right,
parent.height - parent.paddingBottom)
} else {
left = 0
right = parent.width
}
val childCount = parent.childCount
for (i in 0 until childCount - 1) {
val child = parent.getChildAt(i)
parent.getDecoratedBoundsWithMargins(child, mBounds)
val bottom = mBounds.bottom + Math.round(child.translationY)
val top = bottom - mDivider!!.intrinsicHeight
mDivider!!.setBounds(left, top, right, bottom)
mDivider!!.draw(canvas)
}
canvas.restore()
}
private fun drawHorizontal(canvas: Canvas, parent: RecyclerView) {
canvas.save()
val top: Int
val bottom: Int
if (parent.clipToPadding) {
top = parent.paddingTop
bottom = parent.height - parent.paddingBottom
canvas.clipRect(parent.paddingLeft, top,
parent.width - parent.paddingRight, bottom)
} else {
top = 0
bottom = parent.height
}
val childCount = parent.childCount
for (i in 0 until childCount - 1) {
val child = parent.getChildAt(i)
parent.layoutManager.getDecoratedBoundsWithMargins(child, mBounds)
val right = mBounds.right + Math.round(child.translationX)
val left = right - mDivider!!.intrinsicWidth
mDivider!!.setBounds(left, top, right, bottom)
mDivider!!.draw(canvas)
}
canvas.restore()
}