java为什么要使用RecyclerView onDraw延迟
我只想要前三名的孩子。因此,我在正确的时间返回onDraw。但是,我发现项目延迟了。并导致绘制分隔器动作延迟,以循环视图滑动端
下面是我的ItemRaw()方法:
@Override
public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
RecyclerView.Adapter adapter = parent.getAdapter();
if (adapter == null) {
return;
}
int itemCount = adapter.getItemCount();
int lastDividerOffset = getLastDividerOffset(parent);
int validChildCount = parent.getChildCount();
int lastChildPosition = -1;
for (int i = 0; i < validChildCount; i++) {
//只给前三个child设置 divider
View child = parent.getChildAt(i);
int childAdapterPosition = parent.getChildAdapterPosition(child);
if (childAdapterPosition >= 3) {
return;
}
getItemOffsets()方法:
@Override
public void getItemOffsets(Rect rect, View v, RecyclerView parent, RecyclerView.State state) {
final int childCount = parent.getChildCount();
for (int i = 0; i < childCount; i++) {
View child = parent.getChildAt(i);
int childAdapterPosition = parent.getChildAdapterPosition(child);
if (childAdapterPosition >= 3) {
return;
}
}
int position = parent.getChildAdapterPosition(v);
int itemCount = parent.getAdapter().getItemCount();
int lastDividerOffset = getLastDividerOffset(parent);
if (!mShowLastDivider && position >= itemCount - lastDividerOffset) {
// Don't set item offset for last line if mShowLastDivider = false
return;
}
int groupIndex = getGroupIndex(position, parent);
if (mVisibilityProvider.shouldHideDivider(groupIndex, parent)) {
return;
}
setItemOffsets(rect, groupIndex, parent);
}
谢谢
# 1 楼答案
一些xml的设置动画导致了这个问题