How to add a Onclick listener on a RecyclerView in Android Studio with Kotlin?

问题

so I want to have a onclicklistener for my RecyclerView in Android but I am not sure how I should do that.

I have a CustomAdapterClass for my Workoutlist that looks like this:

class CustomAdapter(val workoutList: ArrayList<workout>) : RecyclerView.Adapter<CustomAdapter.ViewHolder>() {

override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): CustomAdapter.ViewHolder {
    val v = LayoutInflater.from(parent.context).inflate(R.layout.list_layout, parent, false)
    return ViewHolder(v)
}

override fun onBindViewHolder(holder: CustomAdapter.ViewHolder, position: Int) {
    holder.bindItems(workoutList[position])
}

override fun getItemCount(): Int {
    return workoutList.size
}

class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {

    fun bindItems(workout: workout) {
        val cardDate = itemView.findViewById<TextView>(R.id.cardDate)
        val cardDescription  = itemView.findViewById<TextView>(R.id.cardDescription)
        cardDate.text = workout.date
        cardDescription.text = workout.description
    }
}
}

And I push my workouts in like this (in my Main Activity):

    val recyclerView = findViewById<RecyclerView>(R.id.RecyclerView)

    recyclerView.layoutManager = GridLayoutManager(this, 3)


    val workouts = ArrayList<workout>()

    workouts.add(workout("12.09.2018", "Kniebeugen und Bizeps + Rücken"))
    workouts.add(workout("12.09.2018", "Kniebeugen und Bizeps + Rücken"))
    workouts.add(workout("12.09.2018", "Kniebeugen und Bizeps + Rücken"))
    workouts.add(workout("12.09.2018", "Kniebeugen und Bizeps + Rücken"))
    workouts.add(workout("12.09.2018", "Kniebeugen und Bizeps + Rücken"))
    workouts.add(workout("12.09.2018", "Kniebeugen und Bizeps + Rücken"))
    workouts.add(workout("12.09.2018", "Kniebeugen und Bizeps + Rücken"))
    workouts.add(workout("12.09.2018", "Kniebeugen und Bizeps + Rücken"))

    val adapter = CustomAdapter(workouts)

    recyclerView.adapter = adapter

I would like to make my workouts clickable and so I can use the name and the description from the workout to open a new activity with them as the intention.

Any help is appreciated!

I do not get where he put that extension in the "duplicate"

回答1:

Let's define an interface for this use-case:

interface WorkoutClickLisetner{
   fun onWorkoutClicked(workout: workout)
}

Add WorkoutClickListener as member of CustomAdapter

var listener : WorkoutClickListener? = null

itemView.listener = object : View.OnClickListener {

  override fun onClick(v: View){
    listener?.onWorkoutClicked(workout)
  }
}

Do not forget to init your WorkoutClickListener where you will delegate action when user clicks the cell:

val adapter = CustomAdapter(workouts)

adapter.listener = object : WorkoutClickListener { 
    override fun onWorkoutClicked(workout: workout){  
   /*your delegation goes here*/`
 }
}

recyclerView.adapter = adapter

回答2:

use it inside viewHolder

  override fun onClick(view: View) {

    }

if you have specific id's

@OnClick(R.id.id1, R.id.id2)
 fun onClick(view: View) {
        when (view.id) {

            R.id.id1 -> {}
            R.id.id2 -> {}
            else ->{}
       }
}

回答3:

Alright guys I found out how to implement a onclicklistener in Kotlin, here is the link: https://gist.github.com/nesquena/231e356f372f214c4fe6

来源：https://stackoverflow.com/questions/47377929/how-to-add-a-onclick-listener-on-a-recyclerview-in-android-studio-with-kotlin

标签

android

android-recyclerview

kotlin