如何使用接口 android 在适配器中创建 onclick 事件?
How to create onclick event in adapter using interface android?
如何使用界面创建点击事件?
在我的应用程序中,我创建了视图点击界面来检测点击适配器项到父 activity。在适配器中创建接口和方法后,如何使用此接口调用视图侦听器?
请检查此代码,它对我来说工作正常。
首先创建适配器class。
class ChapterAdapter(private val activity: Activity, val mWords: ArrayList<Chapter>, val btnlistener: BtnClickListener) : RecyclerView.Adapter<ChapterAdapter.ViewHolder>() {
companion object {
var mClickListener: BtnClickListener? = null
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val layoutInflater = LayoutInflater.from(parent.context)
return ViewHolder(layoutInflater.inflate(R.layout.layout_capter_raw, parent, false))
}
override fun onBindViewHolder(holder: ViewHolder?, position: Int) {
mClickListener = btnlistener
val item = mWords[position]
holder.layout_chapter_name.setOnClickListener(object : View.OnClickListener {
override fun onClick(v: View?) {
if (mClickListener != null)
mClickListener?.onBtnClick(position)
}
})
}
override fun getItemCount(): Int {
return mWords.size
}
override fun getItemId(position: Int): Long {
return super.getItemId(position)
}
override fun getItemViewType(position: Int): Int {
return super.getItemViewType(position)
}
class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
val txt_capter_name = view.txt_capter_name
}
open interface BtnClickListener {
fun onBtnClick(position: Int)
}
}
在您的 Activity 或 Fragment 中创建并声明适配器后。
listAdapter = ChapterAdapter(activity, _arrChapterList, object : ChapterAdapter.BtnClickListener {
override fun onBtnClick(position: Int, chapter_id: String, chapter_size: String, chapter_name: String) {
toast(chapter_id + " = " + chapter_size, Toast.LENGTH_LONG)
}
})
在 Kotlin 中,正确的做法是使用回调而不是 Java Interfaces
。示例:
class MyAdapter(private val callback: (YourModel) -> Unit) {
override fun onBindViewHolder(holder: DataBoundViewHolder<YourModel>, position: Int) {
bind(holder.binding, items!![position])
holder.binding.executePendingBindings()
holder.binding.root.setOnClickListener { callback(binding.model) }
}
}
并使用
在某处创建适配器
MyAdapter myAdapter = MyAdapter( { println{"Clicked $it"} })
编辑:由于提问者希望看到完整的工作代码,我使用了 Sumit 的代码并将接口替换为 Kotlin-Callbacks。
class ChapterAdapter(private val activity: Activity,
val mWords: ArrayList<Chapter>,
val callback: (Any) -> Unit) :
RecyclerView.Adapter<ChapterAdapter.ViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val layoutInflater = LayoutInflater.from(parent.context)
return ViewHolder(layoutInflater.inflate(R.layout.layout_capter_raw, parent, false))
}
override fun onBindViewHolder(holder: ViewHolder?, position: Int) {
val item = mWords[position]
holder.layout_chapter_name.setOnClickListener( callback {$it})
}
override fun getItemCount(): Int = mWords.size
override fun getItemId(position: Int): Long = super.getItemId(position)
override fun getItemViewType(position: Int): Int = super.getItemViewType(position)
class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
val txt_capter_name = view.txt_capter_name
}
最后创建适配器
listAdapter = ChapterAdapter(activity, _arrChapterList, {
toast( "Clicked $it", Toast.LENGTH_LONG)
})
我有同样的问题,这是我的解决方案:
package adapter
class MarketplaceListAdapter : RecyclerView.Adapter<MarketplaceListAdapter.ViewHolder> {
private val marketplaceList: ArrayList<Marketplace>
constructor(marketplaceList: ArrayList<Marketplace>) : super() {
this.marketplaceList = marketplaceList
}
private var listener: OnItemClickListener? = null
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
// implementation
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
// implementation
}
override fun getItemId(position: Int): Long {
return 0
}
override fun getItemCount(): Int {
return marketplaceList.size
}
fun setListener(listener: OnItemClickListener) {
this.listener = listener
}
interface OnItemClickListener {
fun onItemClick(marketplace: Marketplace)
}
inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView),
View.OnClickListener {
var tvTitle: TextView = itemView.findViewById(R.id.tvTitle)
var ivIcon: ImageView = itemView.findViewById(R.id.ivIcon)
init {
itemView.setOnClickListener(this)
}
override fun onClick(v: View) {
listener?.onItemClick(marketplaceList[adapterPosition])
}
}
}
在我的片段上:
val list = view.findViewById<RecyclerView>(R.id.list)
list?.let {
adapter?.let { adapter ->
list.adapter = adapter
adapter.setListener(object : MarketplaceListAdapter.OnItemClickListener {
override fun onItemClick(marketplace: Marketplace) {
onMarketplaceSelected(marketplace)
}
})
}
}
如何使用界面创建点击事件?
在我的应用程序中,我创建了视图点击界面来检测点击适配器项到父 activity。在适配器中创建接口和方法后,如何使用此接口调用视图侦听器?
请检查此代码,它对我来说工作正常。
首先创建适配器class。
class ChapterAdapter(private val activity: Activity, val mWords: ArrayList<Chapter>, val btnlistener: BtnClickListener) : RecyclerView.Adapter<ChapterAdapter.ViewHolder>() {
companion object {
var mClickListener: BtnClickListener? = null
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val layoutInflater = LayoutInflater.from(parent.context)
return ViewHolder(layoutInflater.inflate(R.layout.layout_capter_raw, parent, false))
}
override fun onBindViewHolder(holder: ViewHolder?, position: Int) {
mClickListener = btnlistener
val item = mWords[position]
holder.layout_chapter_name.setOnClickListener(object : View.OnClickListener {
override fun onClick(v: View?) {
if (mClickListener != null)
mClickListener?.onBtnClick(position)
}
})
}
override fun getItemCount(): Int {
return mWords.size
}
override fun getItemId(position: Int): Long {
return super.getItemId(position)
}
override fun getItemViewType(position: Int): Int {
return super.getItemViewType(position)
}
class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
val txt_capter_name = view.txt_capter_name
}
open interface BtnClickListener {
fun onBtnClick(position: Int)
}
}
在您的 Activity 或 Fragment 中创建并声明适配器后。
listAdapter = ChapterAdapter(activity, _arrChapterList, object : ChapterAdapter.BtnClickListener {
override fun onBtnClick(position: Int, chapter_id: String, chapter_size: String, chapter_name: String) {
toast(chapter_id + " = " + chapter_size, Toast.LENGTH_LONG)
}
})
在 Kotlin 中,正确的做法是使用回调而不是 Java Interfaces
。示例:
class MyAdapter(private val callback: (YourModel) -> Unit) {
override fun onBindViewHolder(holder: DataBoundViewHolder<YourModel>, position: Int) {
bind(holder.binding, items!![position])
holder.binding.executePendingBindings()
holder.binding.root.setOnClickListener { callback(binding.model) }
}
}
并使用
在某处创建适配器MyAdapter myAdapter = MyAdapter( { println{"Clicked $it"} })
编辑:由于提问者希望看到完整的工作代码,我使用了 Sumit 的代码并将接口替换为 Kotlin-Callbacks。
class ChapterAdapter(private val activity: Activity,
val mWords: ArrayList<Chapter>,
val callback: (Any) -> Unit) :
RecyclerView.Adapter<ChapterAdapter.ViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
val layoutInflater = LayoutInflater.from(parent.context)
return ViewHolder(layoutInflater.inflate(R.layout.layout_capter_raw, parent, false))
}
override fun onBindViewHolder(holder: ViewHolder?, position: Int) {
val item = mWords[position]
holder.layout_chapter_name.setOnClickListener( callback {$it})
}
override fun getItemCount(): Int = mWords.size
override fun getItemId(position: Int): Long = super.getItemId(position)
override fun getItemViewType(position: Int): Int = super.getItemViewType(position)
class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
val txt_capter_name = view.txt_capter_name
}
最后创建适配器
listAdapter = ChapterAdapter(activity, _arrChapterList, {
toast( "Clicked $it", Toast.LENGTH_LONG)
})
我有同样的问题,这是我的解决方案:
package adapter
class MarketplaceListAdapter : RecyclerView.Adapter<MarketplaceListAdapter.ViewHolder> {
private val marketplaceList: ArrayList<Marketplace>
constructor(marketplaceList: ArrayList<Marketplace>) : super() {
this.marketplaceList = marketplaceList
}
private var listener: OnItemClickListener? = null
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
// implementation
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
// implementation
}
override fun getItemId(position: Int): Long {
return 0
}
override fun getItemCount(): Int {
return marketplaceList.size
}
fun setListener(listener: OnItemClickListener) {
this.listener = listener
}
interface OnItemClickListener {
fun onItemClick(marketplace: Marketplace)
}
inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView),
View.OnClickListener {
var tvTitle: TextView = itemView.findViewById(R.id.tvTitle)
var ivIcon: ImageView = itemView.findViewById(R.id.ivIcon)
init {
itemView.setOnClickListener(this)
}
override fun onClick(v: View) {
listener?.onItemClick(marketplaceList[adapterPosition])
}
}
}
在我的片段上:
val list = view.findViewById<RecyclerView>(R.id.list)
list?.let {
adapter?.let { adapter ->
list.adapter = adapter
adapter.setListener(object : MarketplaceListAdapter.OnItemClickListener {
override fun onItemClick(marketplace: Marketplace) {
onMarketplaceSelected(marketplace)
}
})
}
}