JAVA代码：
public class LinearLayoutDivider extends RecyclerView.ItemDecoration {
private Paint mPaint;
private Drawable mDivider;
private int mDividerHeight = 2;//分割线高度，默认为1px
private int mOrientation;//列表的方向：LinearLayoutManager.VERTICAL或LinearLayoutManager.HORIZONTAL
private static final int[] ATTRS = new int[]{android.R.attr.listDivider};
/**
* 默认分割线：高度为2px，颜色为灰色
*
* @param context
* @param orientation 列表方向
*/
public LinearLayoutDivider(Context context, int orientation) {
if (orientation != LinearLayoutManager.VERTICAL && orientation != LinearLayoutManager.HORIZONTAL) {
throw new IllegalArgumentException("请输入正确的参数！");
}
mOrientation = orientation;
final TypedArray a = context.obtainStyledAttributes(ATTRS);
mDivider = a.getDrawable(0);
a.recycle();
}
/**
* 自定义分割线
*
* @param context
* @param orientation 列表方向
* @param drawableId 分割线图片
*/
public LinearLayoutDivider(Context context, int orientation, int drawableId) {
this(context, orientation);
mDivider = ContextCompat.getDrawable(context, drawableId);
mDividerHeight = mDivider.getIntrinsicHeight();
}
/**
* 自定义分割线
*
* @param context
* @param orientation 列表方向
* @param dividerHeight 分割线高度
* @param dividerColor 分割线颜色
*/
public LinearLayoutDivider(Context context, int orientation, int dividerHeight, int dividerColor) {
this(context, orientation);
mDividerHeight = dividerHeight;
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setColor(dividerColor);
mPaint.setStyle(Paint.Style.FILL);
}
//获取分割线尺寸
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
super.getItemOffsets(outRect, view, parent, state);
if (mOrientation == LinearLayoutManager.VERTICAL) {
outRect.set(0, 0, 0, mDividerHeight);
} else {
outRect.set(0, 0, mDividerHeight, 0);
}
}
//绘制分割线
@Override
public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
super.onDraw(c, parent, state);
if (mOrientation == LinearLayoutManager.VERTICAL) {
drawVertical(c, parent);
} else {
drawHorizontal(c, parent);
}
}
/**
* 绘制纵向列表时的分隔线 这时分隔线是横着的
* 每次 left相同，top根据child变化，right相同，bottom也变化
* @param canvas
* @param parent
*/
private void drawVertical(Canvas canvas, RecyclerView parent) {
final int left = parent.getPaddingLeft();
final int right = parent.getMeasuredWidth() - parent.getPaddingRight();
final int childSize = parent.getChildCount();
for (int i = 0; i < childSize; i++) {
final View child = parent.getChildAt(i);
RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams) child.getLayoutParams();
final int top = child.getBottom() + layoutParams.bottomMargin;
final int bottom = top + mDividerHeight;
if (mDivider != null) {
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(canvas);
}
if (mPaint != null) {
canvas.drawRect(left, top, right, bottom, mPaint);
}
}
}
/**
* 绘制横向列表时的分隔线 这时分隔线是竖着的
* l、r 变化； t、b 不变
* @param canvas
* @param parent
*/
private void drawHorizontal(Canvas canvas, RecyclerView parent) {
final int top = parent.getPaddingTop();
final int bottom = parent.getMeasuredHeight() - parent.getPaddingBottom();
final int childSize = parent.getChildCount();
for (int i = 0; i < childSize; i++) {
final View child = parent.getChildAt(i);
RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams) child.getLayoutParams();
final int left = child.getRight() + layoutParams.rightMargin;
final int right = left + mDividerHeight;
if (mDivider != null) {
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(canvas);
}
if (mPaint != null) {
canvas.drawRect(left, top, right, bottom, mPaint);
}
}
}
}
Kotlin代码：
class LinearLayoutDivider(context: Context, private val mOrientation: Int) : RecyclerView.ItemDecoration() {
private var mPaint: Paint? = null
private var mDivider: Drawable? = null
private var mDividerHeight = 2//分割线高度，默认为1px
private val attrs = intArrayOf(android.R.attr.listDivider)
init {
if (mOrientation != LinearLayoutManager.VERTICAL && mOrientation != LinearLayoutManager.HORIZONTAL) {
throw IllegalArgumentException("请输入正确的参数！")
}
val a = context.obtainStyledAttributes(attrs)
mDivider = a.getDrawable(0)
a.recycle()
}
/**
* 自定义分割线
*
* @param context
* @param orientation 列表方向
* @param drawableId 分割线图片
*/
constructor(context: Context, orientation: Int, drawableId: Int) : this(context, orientation) {
mDivider = ContextCompat.getDrawable(context, drawableId)
mDividerHeight = mDivider!!.intrinsicHeight
}
/**
* 自定义分割线
*
* @param context
* @param orientation 列表方向
* @param dividerHeight 分割线高度
* @param dividerColor 分割线颜色
*/
constructor(context: Context, orientation: Int, dividerHeight: Int, dividerColor: Int) : this(context, orientation) {
mDividerHeight = dividerHeight
mPaint = Paint(Paint.ANTI_ALIAS_FLAG)
mPaint!!.color = dividerColor
mPaint!!.style = Paint.Style.FILL
}
//获取分割线尺寸
override fun getItemOffsets(outRect: Rect, view: View, parent: RecyclerView, state: RecyclerView.State) {
super.getItemOffsets(outRect, view, parent, state)
if (mOrientation == LinearLayoutManager.VERTICAL) {
outRect.set(0, 0, 0, mDividerHeight)
} else {
outRect.set(0, 0, mDividerHeight, 0)
}
}
//绘制分割线
override fun onDraw(c: Canvas, parent: RecyclerView, state: RecyclerView.State) {
super.onDraw(c, parent, state)
if (mOrientation == LinearLayoutManager.VERTICAL) {
drawVertical(c, parent)
} else {
drawHorizontal(c, parent)
}
}
/**
* 绘制纵向列表时的分隔线 这时分隔线是横着的
* 每次 left相同，top根据child变化，right相同，bottom也变化
* @param canvas
* @param parent
*/
private fun drawVertical(canvas: Canvas, parent: RecyclerView) {
val left = parent.paddingLeft
val right = parent.measuredWidth - parent.paddingRight
val childSize = parent.childCount
for (i in 0 until childSize) {
val child = parent.getChildAt(i)
val layoutParams = child.layoutParams as RecyclerView.LayoutParams
val top = child.bottom + layoutParams.bottomMargin
val bottom = top + mDividerHeight
if (mDivider != null) {
mDivider!!.setBounds(left, top, right, bottom)
mDivider!!.draw(canvas)
}
if (mPaint != null) {
canvas.drawRect(left.toFloat(), top.toFloat(), right.toFloat(), bottom.toFloat(), mPaint!!)
}
}
}
/**
* 绘制横向列表时的分隔线 这时分隔线是竖着的
* l、r 变化； t、b 不变
* @param canvas
* @param parent
*/
private fun drawHorizontal(canvas: Canvas, parent: RecyclerView) {
val top = parent.paddingTop
val bottom = parent.measuredHeight - parent.paddingBottom
val childSize = parent.childCount
for (i in 0 until childSize) {
val child = parent.getChildAt(i)
val layoutParams = child.layoutParams as RecyclerView.LayoutParams
val left = child.right + layoutParams.rightMargin
val right = left + mDividerHeight
if (mDivider != null) {
mDivider!!.setBounds(left, top, right, bottom)
mDivider!!.draw(canvas)
}
if (mPaint != null) {
canvas.drawRect(left.toFloat(), top.toFloat(), right.toFloat(), bottom.toFloat(), mPaint!!)
}
}
}
}
使用方法
添加默认分割线：高度为2px，颜色为灰色
mRecyclerView.addItemDecoration(new LinearLayoutDivider(mContext, LinearLayoutManager.VERTICAL));
添加自定义分割线：可自定义分割线drawable
mRecyclerView.addItemDecoration(new LinearLayoutDivider(mContext, LinearLayoutManager.VERTICAL, R.drawable.divider_mileage));
添加默认分割线：可自定义分割线高度和颜色
mRecyclerView.addItemDecoration(new LinearLayoutDivider(mContext, LinearLayoutManager.VERTICAL, 10, getResources().getColor(R.color.divide_gray_color))));
drawable xml文件
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<size android:height="10dp" />
<solid android:color="#ff999999" />
</shape>
附：使用GridLayoutManager横向均分间距
class SpaceItemDecoration(space:Int,spanCount:Int): RecyclerView.ItemDecoration() {
private var space:Int=0
private var spanCount:Int=0
init {
this.space=space
this.spanCount=spanCount
}
override fun getItemOffsets(outRect: Rect, view: View, parent: RecyclerView, state: RecyclerView.State) {
val column: Int = parent.getChildLayoutPosition(view) % spanCount
outRect.bottom = space
outRect.left = column * space / spanCount
outRect.right = space - (column + 1) * space / spanCount
}
}
