本文为大家分享了三种RecycleView分割线不居中的解决方法，供大家参考，具体内容和如下
方法一：
public class SpacesItemDecoration extends RecyclerView.ItemDecoration { private int mSpace; private int mSpanCount; // RecyclerView有多少列 private boolean mHasPadding; // RecyclerView是否有Padding public SpacesItemDecoration(int mSpace) { this.mSpace = mSpace; this.mHasPadding = true; } public SpacesItemDecoration(int mSpace, boolean hasPadding) { this.mSpace = mSpace; this.mHasPadding = hasPadding; } @Override public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) { // 初始化列数 if (mSpanCount == 0) { this.mSpanCount = ((GridLayoutManager) parent.getLayoutManager()).getSpanCount(); } int position = parent.getChildAdapterPosition(view); // item position int column = position % mSpanCount; // item column if (mHasPadding) { outRect.left = mSpace - column * mSpace / mSpanCount; // spacing - column * ((1f / spanCount) * spacing) outRect.right = (column + 1) * mSpace / mSpanCount; // (column + 1) * ((1f / spanCount) * spacing) if (position < mSpanCount) { // top edge outRect.top = mSpace; } outRect.bottom = mSpace; // item bottom } else { outRect.left = column * mSpace / mSpanCount; // column * ((1f / spanCount) * spacing) outRect.right = mSpace - (column + 1) * mSpace / mSpanCount; // spacing - (column + 1) * ((1f / spanCount) * spacing) if (position >= mSpanCount) { outRect.top = mSpace; // item top } } } public void setHasPadding(boolean hasPadding) { this.mHasPadding = hasPadding; }}
方法二：
public class MutiItemDecoration extends RecyclerView.ItemDecoration { public enum Type { VERTICAL, HORIZONTAL, ALL } private Type type;//分割线类型 private int dividerSize = 10;//分割线尺寸 public MutiItemDecoration(MutiItemDecoration.Type type, int dividerSize) { this.type = type; this.dividerSize = dividerSize; } @Override public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) { int spanCount = getSpanCount(parent); int childCount = parent.getAdapter().getItemCount(); switch (type) { case ALL: if (itemPosition % spanCount == 0) {//第一列 if (isLastRaw(parent, itemPosition, spanCount, childCount)) { outRect.set(0, 0, dividerSize / 2, 0); } else { outRect.set(0, 0, dividerSize / 2, dividerSize); } } else if (itemPosition % spanCount == spanCount - 1) {//最后一列 if (isLastRaw(parent, itemPosition, spanCount, childCount)) { outRect.set(dividerSize / 2, 0, 0, 0); } else { outRect.set(dividerSize / 2, 0, 0, dividerSize); } } else {//中间列 if (isLastRaw(parent, itemPosition, spanCount, childCount)) { outRect.set(dividerSize / 2, 0, dividerSize / 2, 0); } else { outRect.set(dividerSize / 2, 0, dividerSize / 2, dividerSize); } } break; case VERTICAL: if (isLastRaw(parent, itemPosition, spanCount, childCount)) { outRect.set(0, 0, 0, 0); } else { outRect.set(0, 0, 0, dividerSize); } break; case HORIZONTAL: if (isLastColum(parent, itemPosition, spanCount, childCount)) { outRect.set(0, 0, 0, 0); } else { outRect.set(0, 0, dividerSize, 0); } break; } } // 是否是最后一列 private boolean isLastColum(RecyclerView parent, int pos, int spanCount, int childCount) { RecyclerView.LayoutManager layoutManager = parent.getLayoutManager(); if (layoutManager instanceof GridLayoutManager) { if ((pos + 1) % spanCount == 0) return true; } else { if (pos == childCount - 1) return true; } return false; } // 是否是最后一行 private boolean isLastRaw(RecyclerView parent, int pos, int spanCount, int childCount) { RecyclerView.LayoutManager layoutManager = parent.getLayoutManager(); if (layoutManager instanceof GridLayoutManager) { childCount = childCount - childCount % spanCount; if (pos >= childCount) return true; } else { if (pos == childCount - 1) return true; } return false; } //返回列数 private int getSpanCount(RecyclerView parent) { RecyclerView.LayoutManager layoutManager = parent.getLayoutManager(); if (layoutManager instanceof GridLayoutManager) { return ((GridLayoutManager) layoutManager).getSpanCount(); } return -1; }}
方法三：（目前只支持2列）
public class DividerGridItemDecoration extends RecyclerView.ItemDecoration { private static final int[] ATTRS = new int[]{android.R.attr.listDivider}; private Drawable mDivider; public DividerGridItemDecoration(Context context) { final TypedArray a = context.obtainStyledAttributes(ATTRS); mDivider = ContextCompat.getDrawable(context, R.drawable.shape_divider); a.recycle(); } @Override public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) { drawHorizontal(c, parent); drawVertical(c, parent); } private int getSpanCount(RecyclerView parent) { // 列数 int spanCount = -1; RecyclerView.LayoutManager layoutManager = parent.getLayoutManager(); if (layoutManager instanceof GridLayoutManager) { spanCount = ((GridLayoutManager) layoutManager).getSpanCount(); } else if (layoutManager instanceof StaggeredGridLayoutManager) { spanCount = ((StaggeredGridLayoutManager) layoutManager) .getSpanCount(); } return spanCount; } public void drawHorizontal(Canvas c, RecyclerView parent) { int childCount = parent.getChildCount(); for (int i = 0; i < childCount; i++) { final View child = parent.getChildAt(i); final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child .getLayoutParams(); final int left = child.getLeft() - params.leftMargin; final int right = child.getRight() + params.rightMargin + mDivider.getIntrinsicWidth(); final int top = child.getBottom() + params.bottomMargin; final int bottom = top + mDivider.getIntrinsicHeight(); mDivider.setBounds(left, top, right, bottom); mDivider.draw(c); } } public void drawVertical(Canvas c, RecyclerView parent) { final int childCount = parent.getChildCount(); for (int i = 0; i < childCount; i++) { final View child = parent.getChildAt(i); final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child .getLayoutParams(); if (i % 2 == 1) { final int top = child.getTop() - params.topMargin; final int bottom = child.getBottom() + params.bottomMargin; final int left = child.getLeft() - params.rightMargin; final int right = left + mDivider.getIntrinsicWidth() / 2; mDivider.setBounds(left, top, right, bottom); mDivider.draw(c); } else { final int top = child.getTop() - params.topMargin; final int bottom = child.getBottom() + params.bottomMargin; final int left = child.getRight() + params.rightMargin; final int right = left + mDivider.getIntrinsicWidth() / 2; mDivider.setBounds(left, top, right, bottom); mDivider.draw(c); } final int top = child.getTop() - params.topMargin; final int bottom = child.getBottom() + params.bottomMargin; final int left = child.getRight() + params.rightMargin; final int right = left + mDivider.getIntrinsicWidth(); mDivider.setBounds(left, top, right, bottom); mDivider.draw(c); } } private boolean isLastColum(RecyclerView parent, int pos, int spanCount, int childCount) { RecyclerView.LayoutManager layoutManager = parent.getLayoutManager(); if (layoutManager instanceof GridLayoutManager) { if ((pos + 1) % spanCount == 0)// 如果是最后一列，则不需要绘制右边 { return true; } } else if (layoutManager instanceof StaggeredGridLayoutManager) { int orientation = ((StaggeredGridLayoutManager) layoutManager) .getOrientation(); if (orientation == StaggeredGridLayoutManager.VERTICAL) { if ((pos + 1) % spanCount == 0)// 如果是最后一列，则不需要绘制右边 { return true; } } else { childCount = childCount - childCount % spanCount; if (pos >= childCount)// 如果是最后一列，则不需要绘制右边 return true; } } return false; } private boolean isLastRaw(RecyclerView parent, int pos, int spanCount, int childCount) { RecyclerView.LayoutManager layoutManager = parent.getLayoutManager(); if (layoutManager instanceof GridLayoutManager) { childCount = childCount - childCount % spanCount; if (pos >= childCount)// 如果是最后一行，则不需要绘制底部 return true; } else if (layoutManager instanceof StaggeredGridLayoutManager) { int orientation = ((StaggeredGridLayoutManager) layoutManager) .getOrientation(); // StaggeredGridLayoutManager 且纵向滚动 if (orientation == StaggeredGridLayoutManager.VERTICAL) { childCount = childCount - childCount % spanCount; // 如果是最后一行，则不需要绘制底部 if (pos >= childCount) return true; } else // StaggeredGridLayoutManager 且横向滚动 { // 如果是最后一行，则不需要绘制底部 if ((pos + 1) % spanCount == 0) { return true; } } } return false; } @Override public void getItemOffsets(Rect outRect, int itemPosition, RecyclerView parent) { int spanCount = getSpanCount(parent); int childCount = parent.getAdapter().getItemCount(); if (isLastRaw(parent, itemPosition, spanCount, childCount))// 如果是最后一行，则不需要绘制底部 { outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0); } else if (isLastColum(parent, itemPosition, spanCount, childCount))// 如果是最后一列，则不需要绘制右边 { outRect.set(0, 0, 0, mDivider.getIntrinsicHeight()); } else { outRect.set(0, 0, mDivider.getIntrinsicWidth(), mDivider.getIntrinsicHeight()); } }}
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。
这一次是一个告别，或者一个永远的告别，
