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在 Android 中,要实现多选项视图的动画效果,可以使用 RecyclerView
和 ItemAnimator
- 首先,在项目的 build.gradle 文件中添加 RecyclerView 依赖:
dependencies { implementation 'com.android.support:recyclerview-v7:28.0.0' }
- 在布局文件中添加 RecyclerView:
android:id="@+id/recycler_view" android:layout_width="match_parent" android:layout_height="wrap_content"/>
- 创建一个表示选项的数据类:
data class Option(val text: String, var isSelected: Boolean)
- 创建一个用于显示选项的 RecyclerView 适配器:
class OptionsAdapter(private val options: List<Option>) : RecyclerView.Adapter<OptionsAdapter.ViewHolder>() { class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) { val textView: TextView = itemView.findViewById(R.id.option_text) } override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder { val view = LayoutInflater.from(parent.context).inflate(R.layout.option_item, parent, false) return ViewHolder(view) } override fun onBindViewHolder(holder: ViewHolder, position: Int) { val option = options[position] holder.textView.text = option.text holder.textView.setOnClickListener { option.isSelected = !option.isSelected notifyItemChanged(position) } } override fun getItemCount(): Int = options.size }
- 在 Activity 或 Fragment 中设置 RecyclerView 和适配器:
val recyclerView: RecyclerView = findViewById(R.id.recycler_view) recyclerView.layoutManager = LinearLayoutManager(this) recyclerView.adapter = OptionsAdapter(listOf( Option("Option 1", false), Option("Option 2", false), Option("Option 3", false) ))
- 创建一个自定义 ItemAnimator 类以实现动画效果:
class CustomItemAnimator : DefaultItemAnimator() { override fun animateChange( oldHolder: RecyclerView.ViewHolder, newHolder: RecyclerView.ViewHolder, fromX: Int, fromY: Int, toX: Int, toY: Int ): Boolean { if (oldHolder == newHolder) { val view = oldHolder.itemView val animator = ValueAnimator.ofFloat(0f, 1f).apply { addUpdateListener { animation -> val value = animation.animatedValue as Float view.scaleX = 1 - value * 0.1f view.scaleY = 1 - value * 0.1f if (value >= 0.5f) { view.alpha = (1 - value) * 2 } } duration = changeDuration interpolator = interpolator } animator.start() return true } return super.animateChange(oldHolder, newHolder, fromX, fromY, toX, toY) } }
- 将自定义 ItemAnimator 应用到 RecyclerView:
recyclerView.itemAnimator = CustomItemAnimator()
现在,当您点击选项时,它们将以动画形式更改其大小和透明度。您可以根据需要调整动画参数。