点击Kotlin RecyclerView(卡片视图)加载详细信息视图

我有一个片段，它有一个RecyclerView，项目在CardViews中。我有一个适配器，它将用来自newsapi.org的数据填充RecyclerView。我需要实现的是当我点击一个项目(CardView(来加载一个带有图像、标题和描述的活动时。我是科特林的新手，发现自己被困在这里，需要帮助跟进。真的很有帮助。我会附上我的适配器和碎片(它有RecyclerView(。

困扰我的是，我是否应该在onBindViewHolder->中启动活动。。。。cardView.setOnClickListener还是其他？令人困惑的部分是将图像(来自url(设置为将值传递给细节视图。

适配器类

class ArticleAdapter(
private var articleList: ArrayList<Article>
) : RecyclerView.Adapter<ArticleViewHolder>() {
private val placeHolderImage = "https://picsum.photos/200/200/?blur"
private lateinit var viewGroupContext: Context
override fun onCreateViewHolder(viewGroup: ViewGroup, p1: Int): ArticleViewHolder {
viewGroupContext = viewGroup.context
val itemView: View =
LayoutInflater.from(viewGroup.context).inflate(R.layout.article_item, viewGroup, false)
return ArticleViewHolder(itemView)
}
override fun getItemCount(): Int {
return articleList.size
}
override fun onBindViewHolder(articleViewHolder: ArticleViewHolder, itemIndex: Int) {
val article: Article = articleList.get(itemIndex)
setPropertiesForArticleViewHolder(articleViewHolder, article)
articleViewHolder.cardView.setOnClickListener {
//do something
}
}
private fun setPropertiesForArticleViewHolder(
articleViewHolder: ArticleViewHolder,
article: Article
) {
checkForUrlToImage(article, articleViewHolder)
articleViewHolder.title.text = article?.title
articleViewHolder.description.text = article?.description
articleViewHolder.url.text = article?.url
}
private fun checkForUrlToImage(article: Article, articleViewHolder: ArticleViewHolder) {
if (article.urlToImage == null || article.urlToImage.isEmpty()) {
Picasso.get()
.load(placeHolderImage)
.centerCrop()
.fit()
.into(articleViewHolder.urlToImage)
} else {
Picasso.get()
.load(article.urlToImage)
.centerCrop()
.fit()
.into(articleViewHolder.urlToImage)
}
}
fun setArticles(articles: ArrayList<Article>) {
articleList = articles
notifyDataSetChanged()
}
}
//interface ItemClickListener{
//    fun onItemClick(articleList: Article, position:Int)
//}

碎片

class HomeFragment : Fragment(), SwipeRefreshLayout.OnRefreshListener {
//    private lateinit var homeViewModel: HomeViewModel
private val ENDPOINT_URL by lazy { "https://newsapi.org/v2/" }
private lateinit var topHeadlinesEndpoint: TopHeadlinesEndpoint
private lateinit var newsApiConfig: String
private lateinit var articleAdapter: ArticleAdapter
private lateinit var articleList: ArrayList<Article>
private lateinit var userKeyWordInput: String
// RxJava related fields
private lateinit var topHeadlinesObservable: Observable<TopHeadlines>
private lateinit var compositeDisposable: CompositeDisposable
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
return inflater.inflate(R.layout.fragment_home, container, false)
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
swipe_refresh.setOnRefreshListener {
queryTopHeadlines()
//            refreshAction()  //refresh the list
swipe_refresh.isRefreshing = false
}
//Network request
val retrofit: Retrofit = generateRetrofitBuilder()
topHeadlinesEndpoint = retrofit.create(TopHeadlinesEndpoint::class.java)
newsApiConfig = resources.getString(R.string.api_key)
swipe_refresh.setOnRefreshListener(this)
swipe_refresh.setColorSchemeResources(R.color.colorAccent)
articleList = ArrayList()
articleAdapter = ArticleAdapter(articleList)
//        userKeyWordInput = ""
compositeDisposable = CompositeDisposable()
recycler_viewHome.setHasFixedSize(true)
recycler_viewHome.layoutManager = LinearLayoutManager(context)
recycler_viewHome.itemAnimator = DefaultItemAnimator()
recycler_viewHome.adapter = articleAdapter
}
override fun onStart() {
super.onStart()
queryTopHeadlines()
}
override fun onDestroy() {
super.onDestroy()
compositeDisposable.clear()
}
override fun onRefresh() {
queryTopHeadlines()
}
private fun queryTopHeadlines() {
swipe_refresh.isRefreshing = true
topHeadlinesObservable = topHeadlinesEndpoint.getTopHeadlines("us", newsApiConfig)
subscribeObservableOfArticle()
}
private fun subscribeObservableOfArticle() {
articleList.clear()
compositeDisposable.add(
topHeadlinesObservable.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.flatMap {
Observable.fromIterable(it.articles)
}
.subscribeWith(createArticleObserver())
)
}
private fun createArticleObserver(): DisposableObserver<Article> {
return object : DisposableObserver<Article>() {
override fun onNext(article: Article) {
if (!articleList.contains(article)) {
articleList.add(article)
}
}
override fun onComplete() {
showArticlesOnRecyclerView()
}
override fun onError(e: Throwable) {
Log.e("createArticleObserver", "Article error: ${e.message}")
}
}
}
private fun showArticlesOnRecyclerView() {
if (articleList.size > 0) {
empty_text.visibility = View.GONE
retry_fetch_button.visibility = View.GONE
recycler_viewHome.visibility = View.VISIBLE
articleAdapter.setArticles(articleList)
} else {
recycler_viewHome.visibility = View.GONE
empty_text.visibility = View.VISIBLE
retry_fetch_button.visibility = View.VISIBLE
//            retry_fetch_button.setOnClickListener { checkUserKeywordInput()    }
}
swipe_refresh.isRefreshing = false
}
private fun generateRetrofitBuilder(): Retrofit {
return Retrofit.Builder()
.baseUrl(ENDPOINT_URL)
.addConverterFactory(GsonConverterFactory.create())
//Add RxJava2CallAdapterFactory as a Call adapter when building     your Retrofit instance
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.build()
}
}