Java tutorial
/** * Copyright (C) 2013 Romain Guefveneu. * * This file is part of naonedbus. * * Naonedbus is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * Naonedbus is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package net.naonedbus.fragment; import java.io.IOException; import java.util.ArrayList; import java.util.List; import net.naonedbus.BuildConfig; import net.naonedbus.R; import net.naonedbus.bean.async.AsyncResult; import net.naonedbus.widget.PinnedHeaderListView; import org.joda.time.DateTime; import org.json.JSONException; import android.content.Context; import android.database.DataSetObserver; import android.os.Bundle; import android.support.v4.app.LoaderManager.LoaderCallbacks; import android.support.v4.content.AsyncTaskLoader; import android.support.v4.content.Loader; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.View.OnClickListener; import android.view.ViewGroup; import android.view.ViewStub; import android.view.animation.AnimationUtils; import android.widget.AbsListView; import android.widget.AbsListView.OnScrollListener; import android.widget.Adapter; import android.widget.Button; import android.widget.ListAdapter; import android.widget.ListView; import android.widget.TextView; import com.actionbarsherlock.app.SherlockListFragment; import de.keyboardsurfer.android.widget.crouton.Crouton; import de.keyboardsurfer.android.widget.crouton.Style; public abstract class CustomListFragment extends SherlockListFragment implements LoaderCallbacks<AsyncResult<ListAdapter>> { private static enum State { CONTENT, LOADER, MESSAGE; } private static final int LOADER_INIT = 0; private static final int LOADER_REFRESH = 1; private static final String STATE_POSITION = "position"; private static final String STATE_TOP = "top"; private static final String LOG_TAG = "CustomListFragment"; private static final boolean DBG = BuildConfig.DEBUG; int mMessageEmptyTitleId = R.string.error_title_empty; int mMessageEmptySummaryId = R.string.error_summary_empty; int mMessageEmptyDrawableId = R.drawable.ic_sad_face; protected int mLayoutId; protected int mLayoutListHeaderId = R.layout.list_item_header; protected ViewGroup mFragmentView; private int mListViewStatePosition; private int mListViewStateTop; private final List<OnScrollListener> mOnScrollListeners = new ArrayList<AbsListView.OnScrollListener>(); private State mCurrentState; private DateTime mNextUpdate = null; /** Minutes pendant lesquelles le contenu est considr comme jour. */ private int mTimeToLive = 5; public CustomListFragment(final int layoutId) { mLayoutId = layoutId; } public CustomListFragment(final int layoutId, final int layoutListHeaderId) { this(layoutId); mLayoutListHeaderId = layoutListHeaderId; } @Override public void onActivityCreated(final Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "onActivityCreated " + mCurrentState); if (mCurrentState == State.MESSAGE) { mCurrentState = null; if (getListAdapter() == null || getListAdapter().getCount() == 0) { showMessage(mMessageEmptyTitleId, mMessageEmptySummaryId, mMessageEmptyDrawableId); } } } @Override public View onCreateView(final LayoutInflater inflater, final ViewGroup container, final Bundle savedInstanceState) { if (container == null) // must put this in return null; if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "onCreateView " + mCurrentState); if (savedInstanceState != null) { mListViewStatePosition = savedInstanceState.getInt(STATE_POSITION, -1); mListViewStateTop = savedInstanceState.getInt(STATE_TOP, 0); } else { mListViewStatePosition = -1; mListViewStateTop = 0; } mFragmentView = (ViewGroup) inflater.inflate(R.layout.fragment_base, container, false); final View view = inflater.inflate(mLayoutId, container, false); bindView(view, savedInstanceState); mFragmentView.addView(view); setupListView(inflater, mFragmentView); return mFragmentView; } @Override public void onSaveInstanceState(final Bundle outState) { if (isAdded()) { final View v = getListView().getChildAt(0); final int top = (v == null) ? 0 : v.getTop(); outState.putInt(STATE_POSITION, getListView().getFirstVisiblePosition()); outState.putInt(STATE_TOP, top); } super.onSaveInstanceState(outState); } @Override public void onStop() { super.onStop(); if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "onStop"); // mCurrentState = null; } protected void bindView(final View view, final Bundle savedInstanceState) { } private void setupListView(final LayoutInflater inflater, final View view) { final ListView listView = (ListView) mFragmentView.findViewById(android.R.id.list); listView.setOnScrollListener(new OnScrollListener() { @Override public void onScrollStateChanged(final AbsListView view, final int scrollState) { } @Override public void onScroll(final AbsListView view, final int firstVisibleItem, final int visibleItemCount, final int totalItemCount) { triggerOnScrollListeners(listView, firstVisibleItem, visibleItemCount, totalItemCount); } }); if (listView instanceof PinnedHeaderListView) { final PinnedHeaderListView pinnedListView = (PinnedHeaderListView) listView; pinnedListView.setPinnedHeaderView(inflater.inflate(mLayoutListHeaderId, pinnedListView, false)); addOnScrollListener(new OnScrollListener() { @Override public void onScrollStateChanged(final AbsListView view, final int scrollState) { } @Override public void onScroll(final AbsListView view, final int firstVisibleItem, final int visibleItemCount, final int totalItemCount) { final Adapter adapter = getListAdapter(); if (adapter != null && adapter instanceof OnScrollListener) { final OnScrollListener sectionAdapter = (OnScrollListener) adapter; sectionAdapter.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount); } } }); } } public void loadContent() { loadContent((Bundle) null); } public void loadContent(final Bundle bundle) { if (getListAdapter() == null) { if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "loadContent " + getListAdapter()); getLoaderManager().initLoader(LOADER_INIT, bundle, this); } } public void refreshContent() { refreshContent((Bundle) null); } public void refreshContent(final Bundle bundle) { getLoaderManager().restartLoader(LOADER_REFRESH, bundle, this); } protected void addOnScrollListener(final OnScrollListener onScrollListener) { mOnScrollListeners.add(onScrollListener); } private void triggerOnScrollListeners(final AbsListView view, final int firstVisibleItem, final int visibleItemCount, final int totalItemCount) { for (final OnScrollListener l : mOnScrollListeners) { l.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount); } } /** * Dfinir les textes et images affichs si la liste est vide. * * @param titleId * L'identifiant du titre. * @param summaryId * L'identifiant de la description. * @param drawableId * L'identifiant du drawable. */ protected void setEmptyMessageValues(final int titleId, final int summaryId, final int drawableId) { this.mMessageEmptyTitleId = titleId; this.mMessageEmptySummaryId = summaryId; this.mMessageEmptyDrawableId = drawableId; } /** * Afficher l'indicateur de chargement. */ protected void showLoader() { if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "showLoader"); if (State.LOADER == mCurrentState) { if (DBG) Log.e(LOG_TAG + "$" + getClass().getSimpleName(), "\t showLoader NO"); return; } if (DBG) Log.i(LOG_TAG + "$" + getClass().getSimpleName(), "\t showLoader OK"); mCurrentState = State.LOADER; mFragmentView.findViewById(android.R.id.list).setVisibility(View.GONE); if (mFragmentView.findViewById(R.id.fragmentMessage) != null) { mFragmentView.findViewById(R.id.fragmentMessage).setVisibility(View.GONE); } mFragmentView.findViewById(R.id.fragmentLoading).setVisibility(View.VISIBLE); } /** * Afficher le contenu. */ protected void showContent() { if (State.CONTENT == mCurrentState) { return; } if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "showContent"); mCurrentState = State.CONTENT; mFragmentView.findViewById(R.id.fragmentLoading).setVisibility(View.GONE); if (mFragmentView.findViewById(R.id.fragmentMessage) != null) { mFragmentView.findViewById(R.id.fragmentMessage).setVisibility(View.GONE); } final View content = mFragmentView.findViewById(android.R.id.list); if (content.getVisibility() != View.VISIBLE) { content.setVisibility(View.VISIBLE); content.startAnimation(AnimationUtils.loadAnimation(getActivity(), android.R.anim.fade_in)); } // View message = mFragmentView.findViewById(R.id.fragmentMessage); // if (message != null) { // message.setVisibility(View.GONE); // } } /** * Afficher le message avec un symbole d'erreur. * * @param titleRes * L'identifiant du titre. * @param descriptionRes * L'identifiant de la description. */ protected void showError(final int titleRes, final int descriptionRes) { showMessage(getString(titleRes), getString(descriptionRes), R.drawable.warning); } /** * Afficher le message avec un symbole d'erreur. * * @param title * Le titre. * @param description * La description. */ protected void showError(final String title, final String description) { showMessage(title, description, R.drawable.warning); } /** * Afficher le message. * * @param titleRes * L'identifiant du titre. * @param descriptionRes * L'identifiant de la description. * @param drawableRes * L'identifiant du drawable. */ protected void showMessage(final int titleRes, final int descriptionRes, final int drawableRes) { showMessage(getString(titleRes), (descriptionRes != 0) ? getString(descriptionRes) : null, drawableRes); } /** * Afficher un message avec une desciption et un symbole. * * @param title * Le titre. * @param description * La description. * @param drawableRes * L'identifiant du symbole. */ protected void showMessage(final String title, final String description, final int drawableRes) { if (State.MESSAGE == mCurrentState) { return; } if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "showMessage " + title + "\t" + description + "\t" + drawableRes); mCurrentState = State.MESSAGE; mFragmentView.findViewById(android.R.id.list).setVisibility(View.GONE); mFragmentView.findViewById(R.id.fragmentLoading).setVisibility(View.GONE); View message = mFragmentView.findViewById(R.id.fragmentMessage); if (message == null) { final ViewStub messageStrub = (ViewStub) mFragmentView.findViewById(R.id.fragmentMessageStub); message = messageStrub.inflate(); } message.setVisibility(View.VISIBLE); final TextView titleView = (TextView) message.findViewById(android.R.id.title); titleView.setText(title); titleView.setCompoundDrawablesWithIntrinsicBounds(0, drawableRes, 0, 0); final TextView descriptionView = (TextView) message.findViewById(android.R.id.summary); if (description != null) { descriptionView.setText(description); descriptionView.setVisibility(View.VISIBLE); } else { descriptionView.setVisibility(View.GONE); } } /** * Dfinir l'action du bouton lors de l'affichage du message. * * @param title * Le titre du boutton. * @param onClickListener * Son action. */ protected void setMessageButton(final int title, final OnClickListener onClickListener) { setMessageButton(getString(title), onClickListener); } /** * Dfinir l'action du bouton lors de l'affichage du message. * * @param title * Le titre du boutton. * @param onClickListener * Son action. */ protected void setMessageButton(final String title, final OnClickListener onClickListener) { final View message = mFragmentView.findViewById(R.id.fragmentMessage); if (message != null) { final Button button = (Button) message.findViewById(android.R.id.button1); button.setText(title); button.setOnClickListener(onClickListener); button.setVisibility(View.VISIBLE); } } /** * Dfinir le nombre de minutes pendant lesquelles les donnes sont * considres comme jour * * @param timeToLive */ protected void setTimeToLive(final int timeToLive) { this.mTimeToLive = timeToLive; } /** * Redfinir la date d'expiration du cache maintenant */ protected void resetNextUpdate() { mNextUpdate = new DateTime().plusMinutes(mTimeToLive); } /** * Indique si les donnes sont toujours considres comme jour ou non * * @return true si elle ne sont plus jour | false si elle sont jour */ protected boolean isNotUpToDate() { if (mNextUpdate != null) { return (mNextUpdate.isBeforeNow()); } else { return true; } } /** * Avant le chargement. */ protected void onPreExecute() { } /** * Charger le contenu en background. * * @return AsyncResult du resultat. */ protected abstract AsyncResult<ListAdapter> loadContent(final Context context, final Bundle bundle); /** * Aprs le chargement. */ protected void onPostExecute() { } @Override public Loader<AsyncResult<ListAdapter>> onCreateLoader(final int loaderId, final Bundle bundle) { if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "onCreateLoader"); final Loader<AsyncResult<ListAdapter>> loader = new AsyncTaskLoader<AsyncResult<ListAdapter>>( getActivity()) { private AsyncResult<ListAdapter> mResult; @Override public AsyncResult<ListAdapter> loadInBackground() { if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "loadInBackground"); return loadContent(getActivity(), bundle); } /** * Called when there is new data to deliver to the client. The super * class will take care of delivering it; the implementation here * just adds a little more logic. */ @Override public void deliverResult(final AsyncResult<ListAdapter> result) { mResult = result; if (isStarted()) { // If the Loader is currently started, we can immediately // deliver its results. try { super.deliverResult(result); } catch (final NullPointerException e) { } } } /** * Handles a request to start the Loader. */ @Override protected void onStartLoading() { if (mResult != null) { // If we currently have a result available, deliver it // immediately. deliverResult(mResult); } if (takeContentChanged() || mResult == null) { // If the data has changed since the last time it was loaded // or is not currently available, start a load. forceLoad(); } } }; if (getListAdapter() == null || getListAdapter().getCount() == 0) showLoader(); onPreExecute(); return loader; } @Override public void onLoadFinished(final Loader<AsyncResult<ListAdapter>> loader, final AsyncResult<ListAdapter> result) { if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "onLoadFinished " + result); if (result == null) { showMessage(mMessageEmptyTitleId, mMessageEmptySummaryId, mMessageEmptyDrawableId); return; } final Exception exception = result.getException(); if (exception == null) { final ListAdapter adapter = result.getResult(); setListAdapter(adapter); if (adapter == null) { showMessage(mMessageEmptyTitleId, mMessageEmptySummaryId, mMessageEmptyDrawableId); } else { adapter.registerDataSetObserver(new DataSetObserver() { @Override public void onChanged() { super.onChanged(); onListAdapterChange(adapter); } }); if (adapter.getCount() > 0) { if (mListViewStatePosition != -1 && isAdded()) { getListView().setSelectionFromTop(mListViewStatePosition, mListViewStateTop); mListViewStatePosition = -1; } showContent(); resetNextUpdate(); } else { showMessage(mMessageEmptyTitleId, mMessageEmptySummaryId, mMessageEmptyDrawableId); } } } else { int titleRes = R.string.error_title; int messageRes = R.string.error_summary; int drawableRes = R.drawable.warning; // Erreur rseau ou interne ? if (exception instanceof IOException) { titleRes = R.string.error_title_network; messageRes = R.string.error_summary_network; drawableRes = R.drawable.ic_thunderstorm; } else if (exception instanceof JSONException) { titleRes = R.string.error_title_webservice; messageRes = R.string.error_summary_webservice; } if (getListAdapter() == null || getListAdapter().isEmpty()) { showMessage(titleRes, messageRes, drawableRes); } else { Crouton.makeText(getActivity(), titleRes, Style.ALERT, (ViewGroup) getView()).show(); } Log.e(getClass().getSimpleName(), "Erreur de chargement.", exception); } onPostExecute(); } @Override public void onLoaderReset(final Loader<AsyncResult<ListAdapter>> arg0) { } @Override public void setListAdapter(final ListAdapter adapter) { if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "setListAdapter " + adapter); super.setListAdapter(adapter); } /** * Gestion du changement du contenu de l'adapter : affichage ou non du * message comme quoi la liste est vide. * * @param adapter */ public void onListAdapterChange(final ListAdapter adapter) { if (DBG) Log.d(LOG_TAG + "$" + getClass().getSimpleName(), "onListAdapterChange"); if (adapter == null || adapter.getCount() == 0) { showMessage(mMessageEmptyTitleId, mMessageEmptySummaryId, mMessageEmptyDrawableId); } else { showContent(); } } }