2021/11/10日高德的首页效果是这样的

然后我的效果

关键代码

 behavior.addBottomSheetCallback(object : BottomSheetBehavior.BottomSheetCallback() {
            override fun onStateChanged(bottomSheet: View, newState: Int) {
                //3 STATE_EXPANDED 4  STATE_COLLAPSED 5 STATE_HIDDEN
                Log.d("Swt", "newState" + newState)
                if (newState == BottomSheetBehavior.STATE_SETTLING) {
                    if (lastNewState == BottomSheetBehavior.STATE_EXPANDED) {
                        if (mSlideOffset < 1f) {
                            behavior.state = BottomSheetBehavior.STATE_HALF_EXPANDED
                            lastNewState = BottomSheetBehavior.STATE_HALF_EXPANDED
                        }
                        return
                    }

                    if (lastNewState == BottomSheetBehavior.STATE_HALF_EXPANDED) {
                        if (mSlideOffset > halfExpandedRatio) {
                            behavior.state = BottomSheetBehavior.STATE_EXPANDED
                            lastNewState = BottomSheetBehavior.STATE_EXPANDED

                        }
                        if (mSlideOffset < halfExpandedRatio) {
                            behavior.state = BottomSheetBehavior.STATE_COLLAPSED
                            lastNewState = BottomSheetBehavior.STATE_COLLAPSED
                        }
                        return
                    }
                    if (lastNewState == BottomSheetBehavior.STATE_COLLAPSED && mSlideOffset > peekRatio) {
                        behavior.state = BottomSheetBehavior.STATE_HALF_EXPANDED
                        lastNewState = BottomSheetBehavior.STATE_HALF_EXPANDED
                        return
                    }
                }
            }

            override fun onSlide(bottomSheet: View, slideOffset: Float) {
                Log.d("Swt", "slideOffset" + slideOffset)
                mSlideOffset = slideOffset
            }

        })

代码地址
https://github.com/BigSweet/GDHome
有用的话点个start，自己研究写的，网上一般都是自定义的behavior，我发现bottomsheet自己就有三级状态直接用一个变量控制实现了