问题描述
<CoordinatorLayout>
<AppBarLayout>
<CollapsingToolbarLayout>
<Toolbar/>
</CollapsingToolbarLayout>
<View1/>
<View2/>
<View3/>
</AppBarLayout>
<RecyclerView/>(app_bar_scrolling_behavior)
</CoordinatorLayout>
我想以编程方式滚动到view3以便对recyclerview中的某个项目进行操作。对此有什么解决方案吗?
解决方法
能够通过使用值动画师使用下面的代码片段来实现这一点。 `
recyclerview.scrollToPosition(0)
val params = appbar.layoutParams as CoordinatorLayout.LayoutParams
val behavior = params.behavior as AppBarLayout.Behavior?
if (behavior != null) {
val valueAnimator: ValueAnimator = ValueAnimator.ofInt()
valueAnimator.interpolator = DecelerateInterpolator()
valueAnimator.addUpdateListener { animation ->
behavior.topAndBottomOffset = (animation.animatedValue as Int)
appBar.requestLayout()
}
valueAnimator.setIntValues(
0,-appbar.totalScrollRange + view3.root.measuredHeight
)
valueAnimator.duration = 50
valueAnimator.start()
}
`