Java tutorial
/* * Copyright (c) 2015 Fabio Berta * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package ch.berta.fabio.popularmovies.presentation.ui.fragments; import android.content.Context; import android.content.Intent; import android.os.Bundle; import android.support.annotation.NonNull; import android.support.annotation.Nullable; import android.support.annotation.StringRes; import android.support.design.widget.Snackbar; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.support.v4.app.FragmentTransaction; import android.support.v7.widget.GridLayoutManager; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import com.mugen.Mugen; import ch.berta.fabio.popularmovies.BuildConfig; import ch.berta.fabio.popularmovies.R; import ch.berta.fabio.popularmovies.domain.models.Movie; import ch.berta.fabio.popularmovies.domain.models.SnackbarAction; import ch.berta.fabio.popularmovies.databinding.FragmentMovieGridBinding; import ch.berta.fabio.popularmovies.presentation.ui.activities.MovieDetailsActivity; import ch.berta.fabio.popularmovies.presentation.ui.adapters.MoviesRecyclerAdapter; import ch.berta.fabio.popularmovies.presentation.ui.adapters.decorators.PosterGridItemDecoration; import ch.berta.fabio.popularmovies.utils.WorkerUtils; import ch.berta.fabio.popularmovies.presentation.viewmodels.MovieGridViewModel; import ch.berta.fabio.popularmovies.presentation.viewmodels.MovieGridViewModelOnl; import ch.berta.fabio.popularmovies.presentation.workerfragments.QueryMoviesWorker; /** * Displays a grid of movie poster images. */ public class MovieGridOnlFragment extends MovieGridBaseFragment implements MovieGridViewModelOnl.ViewInteractionListener { public static final String INTENT_MOVIE_SELECTED = BuildConfig.APPLICATION_ID + ".intents.MOVIE_SELECTED"; private static final String LOG_TAG = MovieGridOnlFragment.class.getSimpleName(); private MoviesRecyclerAdapter mRecyclerAdapter; private FragmentMovieGridBinding mBinding; private MovieGridViewModelOnl mViewModel; private FragmentInteractionListener mActivity; public MovieGridOnlFragment() { // required empty constructor } public static MovieGridOnlFragment newInstance(@NonNull MovieGridViewModel viewModel) { MovieGridOnlFragment fragment = new MovieGridOnlFragment(); Bundle args = new Bundle(); args.putParcelable(KEY_VIEW_MODEL, viewModel); fragment.setArguments(args); return fragment; } @Override public void onAttach(Context context) { super.onAttach(context); try { mActivity = (FragmentInteractionListener) context; } catch (ClassCastException e) { throw new ClassCastException(context.toString() + " must implement FragmentInteractionListener"); } } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Bundle args = getArguments(); if (args != null) { mViewModel = args.getParcelable(KEY_VIEW_MODEL); } } @Nullable @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { mBinding = FragmentMovieGridBinding.inflate(inflater, container, false); mBinding.setViewModel(mViewModel); return mBinding.getRoot(); } @Override public void onViewCreated(View view, Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); if (mViewModel.isRefreshing()) { // work around bug in SwipeRefreshLayout that prevents changing refresh state before it // is laid out, TODO: remove once bug is fixed mBinding.srlGrid.post(new Runnable() { @Override public void run() { mBinding.srlGrid.setRefreshing(true); } }); } } @Override protected void setupRecyclerView() { final int spanCount = getResources().getInteger(R.integer.span_count); GridLayoutManager layoutManager = new GridLayoutManager(getActivity(), spanCount); layoutManager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() { @Override public int getSpanSize(int position) { int viewType = mRecyclerAdapter.getItemViewType(position); return viewType == MovieGridViewModelOnl.TYPE_PROGRESS ? spanCount : 1; } }); mBinding.rvGrid.setLayoutManager(layoutManager); mBinding.rvGrid.setHasFixedSize(true); mBinding.rvGrid.addItemDecoration( new PosterGridItemDecoration(getResources().getDimensionPixelSize(R.dimen.grid_padding))); mRecyclerAdapter = new MoviesRecyclerAdapter(mViewModel, getLayoutWidth(), spanCount); mBinding.rvGrid.setAdapter(mRecyclerAdapter); Mugen.with(mBinding.rvGrid, mViewModel).start(); } @Override public void onStart() { super.onStart(); mViewModel.attachView(this); mViewModel.loadMovies(); } @Override public void onStop() { super.onStop(); mViewModel.detachView(); } @Override public void onDetach() { super.onDetach(); mActivity = null; } @Override public void loadQueryMoviesWorker(int moviePage, @NonNull String sortOption, boolean forceNewQuery) { FragmentManager fragmentManager = getFragmentManager(); Fragment worker = WorkerUtils.findWorker(fragmentManager, QueryMoviesWorker.WORKER_TAG); if (worker == null) { worker = QueryMoviesWorker.newInstance(moviePage, sortOption); fragmentManager.beginTransaction().add(worker, QueryMoviesWorker.WORKER_TAG).commit(); } else if (forceNewQuery) { FragmentTransaction transaction = fragmentManager.beginTransaction(); transaction.remove(worker); worker = QueryMoviesWorker.newInstance(moviePage, sortOption); transaction.add(worker, QueryMoviesWorker.WORKER_TAG).commit(); } } @Override public void removeQueryMoviesWorker() { WorkerUtils.removeWorker(getFragmentManager(), QueryMoviesWorker.WORKER_TAG); } @Override public void scrollToPosition(int position) { mBinding.rvGrid.scrollToPosition(position); } @Override public void notifyMoviesChanged() { mRecyclerAdapter.notifyDataSetChanged(); } @Override public void notifyMoviesInserted(int positionStart, int itemCount) { mRecyclerAdapter.notifyItemRangeInserted(positionStart, itemCount); } @Override public void notifyLoadMoreInserted(int position) { mRecyclerAdapter.notifyItemInserted(position); } @Override public void notifyLoadMoreRemoved(int position) { mRecyclerAdapter.notifyItemRemoved(position); } @Override public void showSnackbar(@StringRes int text, @Nullable SnackbarAction action) { Snackbar snackbar = Snackbar.make(mBinding.rvGrid, text, Snackbar.LENGTH_LONG); if (action != null) { snackbar.setAction(action.getActionText(), action); } snackbar.show(); } @Override public void launchDetailsScreen(@NonNull Movie movie, @NonNull View posterSharedElement) { if (!mUseTwoPane) { final Intent intent = new Intent(getActivity(), MovieDetailsActivity.class); intent.putExtra(INTENT_MOVIE_SELECTED, movie); startDetailsActivity(intent, posterSharedElement); } else if (!mViewModel.isMovieSelected(movie)) { mActivity.showDetailsOnlFragment(movie); } } /** * Defines the interaction with the hosting activity */ public interface FragmentInteractionListener { /** * Shows the details screen of a movie. * * @param movie the movie to show the details for */ void showDetailsOnlFragment(@NonNull Movie movie); } }