我正在开发一个android应用程序,我正在使用RecyclerView。我需要在RecyclerView中添加一个分隔符。
我试着加上-
recyclerView.addItemDecoration(new
DividerItemDecoration(getActivity(),
DividerItemDecoration.VERTICAL_LIST));
下面是我的XML代码-
<android.support.v7.widget.RecyclerView
android:id="@+id/drawerList"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="15dp"
/>
下面是一个简单的自定义分割线(垂直分割线/ 1dp高度/黑色)的代码:
假设你有支持库:
compile "com.android.support:recyclerview-v7:25.1.1"
java代码
DividerItemDecoration divider = new DividerItemDecoration(recyclerView.getContext(), DividerItemDecoration.VERTICAL);
divider.setDrawable(ContextCompat.getDrawable(getBaseContext(), R.drawable.my_custom_divider));
recyclerView.addItemDecoration(divider);
然后custom_divide .xml文件示例:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
<size android:height="1dp" />
<solid android:color="@android:color/black" />
</shape>
class ItemOffsetDecoration(
context: Context,
private val paddingLeft: Int,
private val paddingRight: Int
) : RecyclerView.ItemDecoration() {
private var mDivider: Drawable? = null
init {
mDivider = ContextCompat.getDrawable(context, R.drawable.divider_medium)
}
override fun onDrawOver(c: Canvas, parent: RecyclerView, state: RecyclerView.State) {
val left = parent.paddingLeft + paddingLeft
val right = parent.width - parent.paddingRight - paddingRight
val childCount = parent.childCount
for (i in 0 until childCount) {
val child = parent.getChildAt(i)
val params = child.layoutParams as RecyclerView.LayoutParams
val top = child.bottom + params.bottomMargin
val bottom = top + (mDivider?.intrinsicHeight ?: 0)
mDivider?.let {
it.setBounds(left, top, right, bottom)
it.draw(c)
}
}
}
}
你只需要在R.drawable.divider_medium中指定一个颜色
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid android:color="@android:color/black" />
<size
android:height="1dp"
android:width="1dp" />
</shape>
并将它添加到您的recyclerView
recyclerView.addItemDecoration(
ItemOffsetDecoration(
this,
resources.getDimension(resources.getDimension(R.dimen.dp_70).roundToInt()).roundToInt(),
0
)
)
refernce这
Bhuvanesh BS解决方案有效。Kotlin版本:
import android.graphics.Canvas
import android.graphics.drawable.Drawable
import androidx.recyclerview.widget.RecyclerView
class DividerItemDecorator(private val mDivider: Drawable?) : RecyclerView.ItemDecoration() {
override fun onDraw(
canvas: Canvas,
parent: RecyclerView,
state: RecyclerView.State
) {
val dividerLeft = parent.paddingLeft
val dividerRight = parent.width - parent.paddingRight
for (i in 0 until parent.childCount - 1) {
val child = parent.getChildAt(i)
val dividerTop =
child.bottom + (child.layoutParams as RecyclerView.LayoutParams).bottomMargin
val dividerBottom = dividerTop + mDivider!!.intrinsicHeight
mDivider.setBounds(dividerLeft, dividerTop, dividerRight, dividerBottom)
mDivider.draw(canvas)
}
}
}
所有这些答案都让我接近了答案,但它们都遗漏了一个关键细节。经过一番研究,我发现最简单的方法是将以下3个步骤结合起来:
使用支持库的DividerItemDecoration
用正确的颜色创建分隔线
在主题中设置这个分隔符为listDivider
步骤1:在配置RecyclerView时
recyclerView.addItemDecoration(
new DividerItemDecoration(context, layoutManager.getOrientation()));
第二步:在res/drawable/divider_gray.xml这样的文件中
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<size android:width="1px" android:height="1px" />
<solid android:color="@color/gray" />
</shape>
步骤3:在应用程序的主题
<style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
<!-- Other theme items above -->
<item name="android:listDivider">@drawable/divider_gray</item>
</style>
编辑:更新跳过最后的分隔符:
在使用了一些之后,我意识到它在最后一项之后画了一个分隔符,这很烦人。所以我修改了第1步,如下所示,以覆盖在DividerItemDecoration的默认行为(当然,制作一个单独的类是另一种选择):
recyclerView.addItemDecoration(
new DividerItemDecoration(context, layoutManager.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);
}
}
}
);