我实现了一个分页库,但它不能正常工作。我从 github 请求数据并对存储库列表进行分页。该代码运行良好,但在对搜索查询进行多次更改后,它停止加载数据。在调试中,数据总是加载良好。我猜问题是异步的,但我不知道该往哪里看。 我的代码:
Repo数据源
public class RepoDataSource extends PageKeyedDataSource<Integer, Repo> {
@Override
public void loadInitial(@NonNull LoadInitialParams<Integer> params, @NonNull LoadInitialCallback<Integer, Repo> callback) {
Timber.d("Initial RepoDataSource");
try {
Response<RepoSearchResponse> response = githubService.searchRepos(query, firstNumberPage).execute();
RepoSearchResponse repoSearchResponse = response.body();
if (repoSearchResponse != null) {
List<Repo> items = repoSearchResponse.getItems();
callback.onResult(items, 1, 2);
}
} catch (IOException e) {
Timber.i(e);
}
}
@Override
public void loadBefore(@NonNull LoadParams<Integer> params, @NonNull LoadCallback<Integer, Repo> callback) {
}
@Override
public void loadAfter(@NonNull LoadParams<Integer> params, @NonNull LoadCallback<Integer, Repo> callback) {
Timber.d("Fetching next page: %s", params.key);
try {
Response<RepoSearchResponse> response = githubService.searchRepos(query, params.key).execute();
if (response.isSuccessful()) {
RepoSearchResponse repoSearchResponse = response.body();
if (repoSearchResponse != null) {
List<Repo> items = repoSearchResponse.getItems();
callback.onResult(items, params.key + 1);
}
}
} catch (IOException e) {
Timber.i(e);
}
}
}
GithubApiCall
@GET("search/repositories")
Call<RepoSearchResponse> searchRepos(@Query("q") String query, @Query("page") Integer page);
RepoDataSourceFactory
public class RepoDataSourceFactory extends DataSource.Factory<Integer, Repo> {
private GithubService githubService;
private String query;
public RepoDataSourceFactory(GithubService githubService, String query) {
this.githubService = githubService;
this.query = query;
}
@NonNull
@Override
public DataSource<Integer, Repo> create() {
return new RepoDataSource(githubService, query);
}
}
存储库方法
public class RepoRepository {
...
...
public RepoDataSourceFactory getRepoPagedFactory(String query) {
return new RepoDataSourceFactory(githubService, query);
}
}
视图模型
public final class MyViewModel {
...
public MutableLiveData<String> searchQuery = new MutableLiveData<>();
...
public LiveData<PagedList<Repo>> getRepos() {
return Transformations.switchMap(searchQuery, query -> {
RepoDataSourceFactory factory = repository.getRepoPagedFactory(query);
return new LivePagedListBuilder<>(factory, pagedListConfig).build();
});
}
...
public SearchView.OnQueryTextListener listener = new SearchView.OnQueryTextListener() {
@Override
public boolean onQueryTextSubmit(String query) {
if (query != null && !query.trim().equals("")) {
searchQuery.postValue(query);
}
return true;
}
@Override
public boolean onQueryTextChange(String newText) {
return true;
}
};
...
}
在我的活动中
viewModel.getRepos().observe(this, adapter::submitList);