Java tutorial
/** * ownCloud Android client application * * @author David A. Velasco * Copyright (C) 2015 ownCloud Inc. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2, * as published by the Free Software Foundation. * * This program 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 com.cerema.cloud2.ui.preview; import java.lang.ref.WeakReference; import com.cerema.cloud2.R; import com.cerema.cloud2.datamodel.OCFile; import com.cerema.cloud2.ui.fragment.FileFragment; import android.accounts.Account; import android.os.Bundle; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentStatePagerAdapter; import android.view.LayoutInflater; import android.view.View; import android.view.View.OnClickListener; import android.view.ViewGroup; import android.widget.ProgressBar; import android.widget.TextView; import com.cerema.cloud2.lib.common.network.OnDatatransferProgressListener; import com.cerema.cloud2.lib.common.utils.Log_OC; import com.cerema.cloud2.utils.DisplayUtils; /** * This Fragment is used to monitor the progress of a file downloading. */ public class FileDownloadFragment extends FileFragment implements OnClickListener { public static final String EXTRA_FILE = "FILE"; public static final String EXTRA_ACCOUNT = "ACCOUNT"; private static final String EXTRA_ERROR = "ERROR"; private static final String ARG_FILE = "FILE"; private static final String ARG_IGNORE_FIRST = "IGNORE_FIRST"; private static final String ARG_ACCOUNT = "ACCOUNT"; private View mView; private Account mAccount; public ProgressListener mProgressListener; private boolean mListening; private static final String TAG = FileDownloadFragment.class.getSimpleName(); private boolean mIgnoreFirstSavedState; private boolean mError; /** * Public factory method to create a new fragment that shows the progress of a file download. * * Android strongly recommends keep the empty constructor of fragments as the only public constructor, and * use {@link #setArguments(Bundle)} to set the needed arguments. * * This method hides to client objects the need of doing the construction in two steps. * * When 'file' is null creates a dummy layout (useful when a file wasn't tapped before). * * @param file An {@link OCFile} to show in the fragment * @param account An OC account; needed to start downloads * @param ignoreFirstSavedState Flag to work around an unexpected behaviour of {@link FragmentStatePagerAdapter} * TODO better solution */ public static Fragment newInstance(OCFile file, Account account, boolean ignoreFirstSavedState) { FileDownloadFragment frag = new FileDownloadFragment(); Bundle args = new Bundle(); args.putParcelable(ARG_FILE, file); args.putParcelable(ARG_ACCOUNT, account); args.putBoolean(ARG_IGNORE_FIRST, ignoreFirstSavedState); frag.setArguments(args); return frag; } /** * Creates an empty details fragment. * * It's necessary to keep a public constructor without parameters; the system uses it when tries to * reinstantiate a fragment automatically. */ public FileDownloadFragment() { super(); mAccount = null; mProgressListener = null; mListening = false; mIgnoreFirstSavedState = false; mError = false; } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Bundle args = getArguments(); setFile((OCFile) args.getParcelable(ARG_FILE)); // TODO better in super, but needs to check ALL the class extending FileFragment; not right now mIgnoreFirstSavedState = args.getBoolean(ARG_IGNORE_FIRST); mAccount = args.getParcelable(ARG_ACCOUNT); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { super.onCreateView(inflater, container, savedInstanceState); if (savedInstanceState != null) { if (!mIgnoreFirstSavedState) { setFile((OCFile) savedInstanceState.getParcelable(FileDownloadFragment.EXTRA_FILE)); mAccount = savedInstanceState.getParcelable(FileDownloadFragment.EXTRA_ACCOUNT); mError = savedInstanceState.getBoolean(FileDownloadFragment.EXTRA_ERROR); } else { mIgnoreFirstSavedState = false; } } mView = inflater.inflate(R.layout.file_download_fragment, container, false); ProgressBar progressBar = (ProgressBar) mView.findViewById(R.id.progressBar); DisplayUtils.colorPreLollipopHorizontalProgressBar(progressBar); mProgressListener = new ProgressListener(progressBar); (mView.findViewById(R.id.cancelBtn)).setOnClickListener(this); (mView.findViewById(R.id.fileDownloadLL)).setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { ((PreviewImageActivity) getActivity()).toggleFullScreen(); } }); if (mError) { setButtonsForRemote(); } else { setButtonsForTransferring(); } return mView; } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); outState.putParcelable(FileDownloadFragment.EXTRA_FILE, getFile()); outState.putParcelable(FileDownloadFragment.EXTRA_ACCOUNT, mAccount); outState.putBoolean(FileDownloadFragment.EXTRA_ERROR, mError); } @Override public void onStart() { super.onStart(); listenForTransferProgress(); } @Override public void onResume() { super.onResume(); } @Override public void onPause() { super.onPause(); } @Override public void onStop() { leaveTransferProgress(); super.onStop(); } @Override public void onDestroy() { super.onDestroy(); } @Override public View getView() { if (!mListening) { listenForTransferProgress(); } return super.getView() == null ? mView : super.getView(); } @Override public void onClick(View v) { switch (v.getId()) { case R.id.cancelBtn: { mContainerActivity.getFileOperationsHelper().cancelTransference(getFile()); getActivity().finish(); break; } default: Log_OC.e(TAG, "Incorrect view clicked!"); } } /** * Enables or disables buttons for a file being downloaded */ private void setButtonsForTransferring() { getView().findViewById(R.id.cancelBtn).setVisibility(View.VISIBLE); // show the progress bar for the transfer getView().findViewById(R.id.progressBar).setVisibility(View.VISIBLE); TextView progressText = (TextView) getView().findViewById(R.id.progressText); progressText.setText(R.string.downloader_download_in_progress_ticker); progressText.setVisibility(View.VISIBLE); // hides the error icon getView().findViewById(R.id.errorText).setVisibility(View.GONE); getView().findViewById(R.id.error_image).setVisibility(View.GONE); } /** * Enables or disables buttons for a file locally available */ private void setButtonsForDown() { getView().findViewById(R.id.cancelBtn).setVisibility(View.GONE); // hides the progress bar getView().findViewById(R.id.progressBar).setVisibility(View.GONE); // updates the text message TextView progressText = (TextView) getView().findViewById(R.id.progressText); progressText.setText(R.string.common_loading); progressText.setVisibility(View.VISIBLE); // hides the error icon getView().findViewById(R.id.errorText).setVisibility(View.GONE); getView().findViewById(R.id.error_image).setVisibility(View.GONE); } /** * Enables or disables buttons for a file not locally available * <p/> * Currently, this is only used when a download was failed */ private void setButtonsForRemote() { getView().findViewById(R.id.cancelBtn).setVisibility(View.GONE); // hides the progress bar and message getView().findViewById(R.id.progressBar).setVisibility(View.GONE); getView().findViewById(R.id.progressText).setVisibility(View.GONE); // shows the error icon and message getView().findViewById(R.id.errorText).setVisibility(View.VISIBLE); getView().findViewById(R.id.error_image).setVisibility(View.VISIBLE); } public void listenForTransferProgress() { if (mProgressListener != null && !mListening) { if (mContainerActivity.getFileDownloaderBinder() != null) { mContainerActivity.getFileDownloaderBinder().addDatatransferProgressListener(mProgressListener, mAccount, getFile()); mListening = true; setButtonsForTransferring(); } } } public void leaveTransferProgress() { if (mProgressListener != null) { if (mContainerActivity.getFileDownloaderBinder() != null) { mContainerActivity.getFileDownloaderBinder().removeDatatransferProgressListener(mProgressListener, mAccount, getFile()); mListening = false; } } } /** * Helper class responsible for updating the progress bar shown for file uploading or downloading */ private class ProgressListener implements OnDatatransferProgressListener { int mLastPercent = 0; WeakReference<ProgressBar> mProgressBar = null; ProgressListener(ProgressBar progressBar) { mProgressBar = new WeakReference<ProgressBar>(progressBar); } @Override public void onTransferProgress(long progressRate, long totalTransferredSoFar, long totalToTransfer, String filename) { int percent = (int) (100.0 * ((double) totalTransferredSoFar) / ((double) totalToTransfer)); if (percent != mLastPercent) { ProgressBar pb = mProgressBar.get(); if (pb != null) { pb.setProgress(percent); pb.postInvalidate(); } } mLastPercent = percent; } } public void setError(boolean error) { mError = error; } ; }