Android Kotlin RecyclerView 实现水平自动循环滚动 - 使用 BaseRecyclerViewAdapterHelper
要实现水平自动循环滚动的 RecyclerView,可以使用 BaseRecyclerViewAdapterHelper 库来简化操作。下面是实现该功能的步骤:
- 在
build.gradle文件中添加 BaseRecyclerViewAdapterHelper 库的依赖:
implementation 'com.github.CymChad:BaseRecyclerViewAdapterHelper:3.0.10'
- 创建一个自定义的 LayoutManager 类,继承自
LinearLayoutManager,并重写scrollHorizontallyBy()方法来实现循环滚动的效果:
class LoopLinearLayoutManager(context: Context) : LinearLayoutManager(context) {
override fun scrollHorizontallyBy(dx: Int, recycler: RecyclerView.Recycler?, state: RecyclerView.State?): Int {
val orientation = orientation
val scrolled = super.scrollHorizontallyBy(dx, recycler, state)
if (itemCount > 0) {
val childWidth = getChildAt(0)?.width ?: 0
val childCount = childCount
val firstChild = getChildAt(0)
val lastChild = getChildAt(childCount - 1)
if (orientation == HORIZONTAL) {
if (scrolled > 0 && getPosition(firstChild!!) == 0) {
val left = firstChild.left - dx
if (left > 0) {
val newDx = -dx + left
return -newDx
}
} else if (scrolled < 0 && getPosition(lastChild!!) == itemCount - 1) {
val right = lastChild.right - dx
if (right < width) {
val newDx = dx - (width - right)
return -newDx
}
}
}
}
return scrolled
}
}
- 创建一个自定义的 BaseQuickAdapter 类,继承自 BaseQuickAdapter,并在 convert() 方法中设置点击事件:
class MyAdapter(data: List<String>) : BaseQuickAdapter<String, BaseViewHolder>(R.layout.item_layout, data) {
override fun convert(holder: BaseViewHolder, item: String) {
holder.setText(R.id.tv_item, item)
holder.itemView.setOnClickListener {
// 处理点击事件
}
}
}
- 在 Activity 或 Fragment 中使用 RecyclerView,并设置 LayoutManager 和 Adapter:
val recyclerView = findViewById<RecyclerView>(R.id.recycler_view)
val layoutManager = LoopLinearLayoutManager(this)
layoutManager.orientation = LinearLayoutManager.HORIZONTAL
recyclerView.layoutManager = layoutManager
val adapter = MyAdapter(dataList)
recyclerView.adapter = adapter
这样就可以实现水平自动循环滚动的 RecyclerView 了。当滚动时,可以通过触摸停止滚动,松开后会继续滚动。同时,通过点击 RecyclerView 的 item 也可以处理点击事件。
原文地址: http://www.cveoy.top/t/topic/bnm5 著作权归作者所有。请勿转载和采集!