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"
/>
当前回答
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
其他回答
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)
}
}
}
所以这可能不是正确的方式，但我只是添加了一个视图到RecyclerView的单项视图(因为我不认为有一个内置的函数)，像这样:
<View
android:layout_width="fill_parent"
android:layout_height="@dimen/activity_divider_line_margin"
android:layout_alignParentBottom="true"
android:background="@color/tasklist_menu_dividerline_grey" />
这意味着每一项都有一行在底部填充。我把它做成1dp高，背景#111111。这也给了它一种“3D”效果。
您可以创建一个简单的可重复使用的分隔器。
创建分频器:
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; 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);
}
}
}
创建分隔线:separator .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>
为你的Recyclerview添加分隔符:
RecyclerView.ItemDecoration dividerItemDecoration = new DividerItemDecorator(ContextCompat.getDrawable(context, R.drawable.divider));
recyclerView.addItemDecoration(dividerItemDecoration);
删除最后一项的分隔符:
为了防止最后一项画分隔线，你必须改变这条线。
for (int i = 0; i < childCount; i++)
To
for (int i = 0; i < childCount-1; i++)
你的最终实现应该是这样的:
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 - 1; 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);
}
}
}
希望能有所帮助。
Material-IO库中的MaterialDividerItemDecoration是许多用例的完整解决方案，如列表项划分或节划分。它拥有开发人员可能需要的一切，如插图和样式，而无需实现自己的项目装饰。这个材质分割线指南+实现真的很好检查。
如果你想同时使用水平和垂直分隔符:
Define horizontal & vertical divider drawables: horizontal_divider.xml <?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" > <size android:height="1dip" /> <solid android:color="#22000000" /> </shape> vertical_divider.xml <?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" > <size android:width="1dip" /> <solid android:color="#22000000" /> </shape> Add this code segment below: DividerItemDecoration verticalDecoration = new DividerItemDecoration(recyclerview.getContext(), DividerItemDecoration.HORIZONTAL); Drawable verticalDivider = ContextCompat.getDrawable(getActivity(), R.drawable.vertical_divider); verticalDecoration.setDrawable(verticalDivider); recyclerview.addItemDecoration(verticalDecoration); DividerItemDecoration horizontalDecoration = new DividerItemDecoration(recyclerview.getContext(), DividerItemDecoration.VERTICAL); Drawable horizontalDivider = ContextCompat.getDrawable(getActivity(), R.drawable.horizontal_divider); horizontalDecoration.setDrawable(horizontalDivider); recyclerview.addItemDecoration(horizontalDecoration);
