RecyclerView的万能分割线

什么是recyclerview

recyclerview是android 5.0 materials design中的组件之一，相应的还有cardview、palette等。看名字我们就能看出一点端倪，没错，它主要的特点就是复用。我们知道，listview中的adapter中可以实现viewholder的复用。recyclerview提供了一个耦合度更低的方式来复用viewholder，并且可以轻松的实现listview、gridview以及瀑布流的效果。

先给大家展示下效果图：

使用方法：

添加默认分割线：高度为2px，颜色为灰色

mrecyclerview.additemdecoration(new recycleviewdivider(mcontext, linearlayoutmanager.vertical));

添加自定义分割线：可自定义分割线drawable

mrecyclerview.additemdecoration(new recycleviewdivider(
mcontext, linearlayoutmanager.vertical, r.drawable.divider_mileage));

添加自定义分割线：可自定义分割线高度和颜色

mrecyclerview.additemdecoration(new recycleviewdivider(
mcontext, linearlayoutmanager.vertical, 10, getresources().getcolor(r.color.divide_gray_color)));

万能分割线登场：

public class recycleviewdivider 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 recycleviewdivider(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 recycleviewdivider(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 recycleviewdivider(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);
outrect.set(0, 0, 0, mdividerheight);
}
//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);
}
}
//绘制横向 item 分割线
private void drawhorizontal(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);
}
}
}
//绘制纵向 item 分割线
private void drawvertical(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);
}
}
}
}

以上所述是小编给大家介绍的recyclerview的万能分割线，希望对大家有所帮助