前一阵将support库版27.0.0发现了这个问题。发现RecyclerView在滑动到底部后，会有急秒的停滞，之后再去加载下一页数据。
滑动越快，停滞时间越长。我们知道上拉加载实现方案基本都是监听滑动状态，当滑动停止时，再去加载下一页。代码基本如下：
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if (newState == RecyclerView.SCROLL_STATE_IDLE) {
onLoadNextPage();
}
}
具体解决方案如下：
https://juejin.im/entry/5b978fe8f265da0b001f16c0
方案一，重写AppBarLayout.Behavior
代码如下
public class FixAppBarLayoutBehavior extends AppBarLayout.Behavior {
public FixAppBarLayoutBehavior() {
super();
}
public FixAppBarLayoutBehavior(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
public void onNestedPreScroll(CoordinatorLayout coordinatorLayout, AppBarLayout child,
View target, int dx, int dy, int[] consumed, int type) {
super.onNestedPreScroll(coordinatorLayout, child, target, dx, dy, consumed, type);
stopNestedScrollIfNeeded(dy, child, target, type);
}
@Override
public void onNestedScroll(CoordinatorLayout coordinatorLayout, AppBarLayout child, View target,
int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int type) {
super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed, type);
stopNestedScrollIfNeeded(dyUnconsumed, child, target, type);
}
private void stopNestedScrollIfNeeded(int dy, AppBarLayout child, View target, int type) {
if (type == ViewCompat.TYPE_NON_TOUCH) {
final int currOffset = getTopAndBottomOffset();
if ((dy < 0 && currOffset == 0) || (dy > 0 && currOffset == -child.getTotalScrollRange())) {
ViewCompat.stopNestedScroll(target, ViewCompat.TYPE_NON_TOUCH);
}
}
}
}
修改引用
<android.support.design.widget.AppBarLayout
...
app:layout_behavior="yourPackage.FixAppBarLayoutBehavior">
方案二：直接修改support版本，升级到28
