我找不到更好的方式来改变我的VideosDataSource方法,如负载起始listId。我使用的视图寻呼机所以它一次,这就是为什么我不能使用getter / setter方法来设置我的数据源的listId装载2片段。我在这里的数据源类:
class VideosDataSource(
private val networkService: NetworkService,
private val compositeDisposable: CompositeDisposable
): PageKeyedDataSource<String, Item>() {
var state: MutableLiveData<State> = MutableLiveData()
private var retryCompletable: Completable? = null
private var listId = "PL8fVUTBmJhHKEJjTNWn-ykf67rVrFWYtC"
override fun loadInitial(params: LoadInitialParams<String>, callback: LoadInitialCallback<String, Item>) {
updateState(State.LOADING)
compositeDisposable.add(
networkService.getPlaylistVideos(listId
,""
,Constants.API_KEY)
.subscribe( { response ->
updateState(State.DONE)
callback.onResult(response.items, response.prevPageToken, response.nextPageToken)
},
{
updateState(State.ERROR)
setRetry(Action { loadInitial(params,callback) })
}
)
)
}
在这里,我试图改变listId在我看来寻呼机片段。
我的数据源工厂:
class VideosDataSourceFactory(
private val compositeDisposable: CompositeDisposable,
private val networkService: NetworkService
): DataSource.Factory<String, Item>() {
val videosDataSourceLiveData = MutableLiveData<VideosDataSource>()
override fun create(): DataSource<String, Item> {
val videosDataSource = VideosDataSource(networkService,
compositeDisposable)
videosDataSourceLiveData.postValue(videosDataSource)
return videosDataSource
}
}
我的视图模型:
class PageViewModel(application: Application) :
AndroidViewModel(application) {
//paging
private val networkService = NetworkService.getService()
var videosList: LiveData<PagedList<Item>>
private val compositeDisposable = CompositeDisposable()
private val pageSize = 50
private val videosDataSourceFactory: VideosDataSourceFactory
init {
//paging
videosDataSourceFactory = VideosDataSourceFactory(compositeDisposable, networkService)
val config = PagedList.Config.Builder()
.setPageSize(pageSize)
.setInitialLoadSizeHint(pageSize)
.setEnablePlaceholders(false)
.build()
videosList = LivePagedListBuilder<String, Item>(videosDataSourceFactory, config).build()
}
在片段的onClick()我要发送列表中的数据源。
丝毫像的getter / setter一些方法i可为能够发送listId到数据源,但视图寻呼机在时刻的值是在的getter / setter倍率创建两个或三个片段。我在寻找更好的方式来从片段数据发送到数据源。
我做的。构造函数的想法是好的,但没有工作,因为ID设置为出厂构造函数之前称为视图模型的init方法对我来说。但由于mr.pskink对他的评论使用参数的构造函数。
因此,这里是我做到了。在片段我设置列表中查看模型。
companion object {
private const val ARG_SECOND = "arg_second"
@JvmStatic
fun newInstance(second: Array<Pair<String, String>>): PlaceholderFragment {
return PlaceholderFragment().apply {
arguments = Bundle().apply {
putString(ARG_SECOND,second[0].second)
}
}
}
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
viewModel = ViewModelProviders.of(this).get(PageViewModel::class.java).apply {
setListId(arguments?.getString(ARG_SECOND) ?: "")
}
}
在视图模型我创建的方法:
fun setListId(listId: String){
videosDataSourceFactory.listId = listId
}
在数据源工厂我创建一个变量:
val videosDataSourceLiveData = MutableLiveData<VideosDataSource>()
lateinit var listId:String
override fun create(): DataSource<String, Item> {
val videosDataSource = VideosDataSource(networkService, compositeDisposable,listId)
videosDataSourceLiveData.postValue(videosDataSource)
return videosDataSource
}
然后通过这里的数据源的构造得到它:
class VideosDataSource(
private val networkService: NetworkService,
private val compositeDisposable: CompositeDisposable,
private val listId: String
): PageKeyedDataSource<String, Item>() {
var state: MutableLiveData<State> = MutableLiveData()
private var retryCompletable: Completable? = null
override fun loadInitial(params: LoadInitialParams<String>, callback:
LoadInitialCallback<String, Item>) {
updateState(State.LOADING)
compositeDisposable.add(
networkService.getPlaylistVideos(listId
,""
,Constants.API_KEY)
.subscribe( { response ->
updateState(State.DONE)
callback.onResult(response.items, response.prevPageToken, response.nextPageToken)
},
{
updateState(State.ERROR)
setRetry(Action { loadInitial(params,callback) })
}
)
)
}