如何使用 Kotlin 通过数据绑定在 RecyclerView Adapter 中实现 onClick

如何解决如何使用 Kotlin 通过数据绑定在 RecyclerView Adapter 中实现 onClick

我使用数据绑定创建了一个 RecyclerView 适配器，我正在尝试处理该适配器内的 Click 事件，但我不知道具体如何处理。我找到了不同的主题，但还不能解决我的问题。谢谢！ 我应该在哪里（在 Adapter 类中）实现 onClick 函数？

适配器类

class RemovableContactsAdapter(val viewModel: GroupDetailsViewModel,val callback:GroupContactsCallback) : RecyclerView.Adapter<RemovableContactsViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup,viewType: Int): RemovableContactsViewHolder {
    val binding: ViewDataBinding =
        DataBindingUtil.inflate(LayoutInflater.from(parent.context),viewType,parent,false)
    return RemovableContactsViewHolder(binding)
}

override fun onBindViewHolder(holder: RemovableContactsViewHolder,position: Int) {
    holder.bind(viewModel,callback,position)

}

override fun getItemCount(): Int {
    return viewModel.currentGroup.value?.contacts?.size ?: 0
}

override fun getItemViewType(position: Int): Int {
    return R.layout.removable_contact_layout
}
}

class RemovableContactsViewHolder(val binding: ViewDataBinding) :
RecyclerView.ViewHolder(binding.root) {

fun bind(viewModel: GroupDetailsViewModel,callback: GroupContactsCallback,position: Int) {
    binding.root.selected_contact_iv.apply {
        visibility = if (viewModel.currentGroup.value?.contacts!![position].selected) {
            View.VISIBLE
        } else {
            View.GONE
        }
    }
    binding.setVariable(BR.contact,viewModel.currentGroup.value?.contacts?.get(position))
    binding.setVariable(BR.callback,callback)
    binding.executePendingBindings()
   }
}

Fragment 类中的回调接口：

interface GroupContactsCallback {
   fun selectContact(contact: ContactModel)
}

编辑

我更新了 RemovableContactsViewHolder 中的绑定函数，但仍然无法正常工作。

class RemovableContactsViewHolder(val binding: ViewDataBinding) :
RecyclerView.ViewHolder(binding.root) {

fun bind(viewModel: GroupDetailsViewModel,position: Int) {
    itemView.setOnClickListener {
        viewModel.currentGroup.value?.contacts?.get(position)!!.selected = !viewModel.currentGroup.value?.contacts?.get(position)!!.selected
        callback.selectContact(viewModel.currentGroup.value?.contacts?.get(position)!!)
    }

    binding.root.selected_contact_iv.apply {
        visibility = if (viewModel.currentGroup.value?.contacts!![position].selected) {
            View.VISIBLE
        } else {
            View.GONE
        }
    }

    binding.setVariable(BR.contact,callback)
    binding.executePendingBindings()
}

解决方法

处理适配器内部的点击不是一个好习惯。并且不要仅仅为此使用接口。改用这个。

class YourRecyclerViewAdapter(private val onSelect: (YourDataType?) -> Unit) : RecyclerView.Adapter<YourRecyclerViewAdapter.YourViewHolder>() {

    override fun onBindViewHolder(holder: YourViewHolder,position: Int) {
        holder.bind(getItem(position),onSelect)
    }

    class ViewHolder(private val binding: YourViewBinding) : RecyclerView.ViewHolder(binding.root) {

        fun bind(yourDataType: YourDataType?,onSelect: (YourDataType?) -> Unit) {

           // bind your view here
           binding.root.setOnClickListener {
               onSelect(yourDataType)
           }
        }
    }
}

在您的片段/活动中

// Set this adapter to your recycler view
val adapter = YourRecyclerViewAdapter { yourDataType-> 
    // Handle click here
}

,

override fun onBindViewHolder(holder: RemovableContactsViewHolder,position: Int) {
holder.bind(viewModel,callback,position)

holder.binding.your_view_like_button.setOnClickListener {
// do something 
}
}

• 例如

    class AppointTimeSloatAdapter(
        private var mOptionList: List<String>,var context: Context,var appointmentDate: String,) : RecyclerView.Adapter<AppointTimeSloatAdapter.ViewHolder>() {
        private var checkedRadioButton: CompoundButton? = null
  
        override fun onCreateViewHolder(parent: ViewGroup,viewType: Int): ViewHolder {
            val viewProductCategoryBinding: AdapterAppointmentTimeSloteBinding =
                AdapterAppointmentTimeSloteBinding.inflate(
                    LayoutInflater.from(parent.context),parent,false
                )
            return ViewHolder(viewProductCategoryBinding)
        }
  
  
        override fun onBindViewHolder(holder: ViewHolder,position: Int) {
            val option = getItem(position)
            holder.binding.radioBtn.text = option.toString()
  
            holder.binding.radioBtn.setOnCheckedChangeListener(checkedChangeListener)
            if (holder.binding.radioBtn.isChecked) checkedRadioButton = holder.binding.radioBtn
  
            holder.binding.radioBtn.setOnClickListener {
                var intent = Intent(context,NewAppointmentActivity::class.java)
                intent.putExtra("time",holder.binding.radioBtn.text.toString())
                intent.putExtra("appointmentDate",appointmentDate)
                context.startActivity(intent)
            }
  
  
        }
  
        private val checkedChangeListener =
            CompoundButton.OnCheckedChangeListener { compoundButton,isChecked ->
                checkedRadioButton?.apply { setChecked(!isChecked) }
                checkedRadioButton = compoundButton.apply { setChecked(isChecked) }
            }
  
        fun updateList(list: ArrayList<String>) {
            mOptionList = list
            notifyDataSetChanged()
        }
  
  
        private fun getItem(index: Int): String {
            return mOptionList[index]
        }
  
        override fun getItemCount(): Int {
            return mOptionList.size
        }
  
  
        inner class ViewHolder(val binding: AdapterAppointmentTimeSloteBinding) :
            RecyclerView.ViewHolder(binding.root),View.OnClickListener {
            override fun onClick(v: View?) {
                ////
            }
        }
  
    }
  

,

应用以下方法。

在你的适配器类中

class RemovableContactsAdapter(val viewModel: GroupDetailsViewModel,val callback:GroupContactsCallback) : RecyclerView.Adapter<RemovableContactsViewHolder>() {
private var onClickListener: OnClickListener?=null
override fun onCreateViewHolder(parent: ViewGroup,viewType: Int): RemovableContactsViewHolder {
    val binding: ViewDataBinding =
        DataBindingUtil.inflate(LayoutInflater.from(parent.context),viewType,false)
    return RemovableContactsViewHolder(binding)
}

override fun onBindViewHolder(holder: RemovableContactsViewHolder,position: Int) {
    holder.bind(viewModel,position)

holder.itemView.setOnClickListener {
            if(onClickListener!=null){
                onClickListener!!.onClick(position)
            }
        }

}

override fun getItemCount(): Int {
    return viewModel.currentGroup.value?.contacts?.size ?: 0
}

override fun getItemViewType(position: Int): Int {
    return R.layout.removable_contact_layout
}
}

class RemovableContactsViewHolder(val binding: ViewDataBinding) :
RecyclerView.ViewHolder(binding.root) {

fun bind(viewModel: GroupDetailsViewModel,callback: GroupContactsCallback,position: Int) {
    binding.root.selected_contact_iv.apply {
        visibility = if (viewModel.currentGroup.value?.contacts!![position].selected) {
            View.VISIBLE
        } else {
            View.GONE
        }
    }
    binding.setVariable(BR.contact,viewModel.currentGroup.value?.contacts?.get(position))
    binding.setVariable(BR.callback,callback)
    binding.executePendingBindings()
   }

 fun setOnClickListener(onClickListener: OnClickListener){
        this.onClickListener=onClickListener
    }

    interface OnClickListener{
        fun onClick(position: Int)
    }
}

在您的 Activity/Fragment 类中创建一个名为适配器的对象，然后

val adapter=RemovableContactsAdapter(viewModel,callback)
adapter.setOnClickListener(object :SettingAdapter.OnClickListener{
            override fun onClick(position: Int){
                //position is your clicked view position
            }
        })

我在回答中修改了你的代码，希望问题能得到解决。