Java tutorial
/* * Copyright (C) 2012 The Android Open Source Project * * 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 ar.com.lapotoca.resiliencia.gallery.ui; import android.os.Bundle; import android.support.v4.app.Fragment; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ImageView; import android.widget.ProgressBar; import ar.com.lapotoca.resiliencia.R; import ar.com.lapotoca.resiliencia.gallery.provider.ImageHolder; import ar.com.lapotoca.resiliencia.gallery.util.ImageFetcher; import ar.com.lapotoca.resiliencia.gallery.util.ImageWorker; /** * This fragment will populate the children of the ViewPager from {@link ImageDetailActivity}. */ public class ImageDetailFragment extends Fragment implements ImageWorker.OnImageLoadedListener { private static final String IMAGE_DATA_EXTRA = "extra_image_data"; private static final String IMAGE_DATA_SOURCE = "extra_image_source"; private String mImageUrl; private boolean mIsLocal; private ImageView mImageView; private ProgressBar mProgressBar; private ImageFetcher mImageFetcher; /** * Factory method to generate a new instance of the fragment given an image number. * * @param image The image holder to load * @return A new instance of ImageDetailFragment with imageNum extras */ public static ImageDetailFragment newInstance(ImageHolder image) { final ImageDetailFragment f = new ImageDetailFragment(); final Bundle args = new Bundle(); args.putString(IMAGE_DATA_EXTRA, image.getUrl()); args.putBoolean(IMAGE_DATA_SOURCE, image.isLocal()); f.setArguments(args); return f; } /** * Empty constructor as per the Fragment documentation */ public ImageDetailFragment() { } /** * Populate image using a url from extras, use the convenience factory method * {@link ImageDetailFragment#newInstance(ImageHolder)} to create this fragment. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); mImageUrl = getArguments() != null ? getArguments().getString(IMAGE_DATA_EXTRA) : null; mIsLocal = getArguments() != null ? getArguments().getBoolean(IMAGE_DATA_SOURCE) : false; } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { // Inflate and locate the main ImageView final View v = inflater.inflate(R.layout.image_detail_fragment, container, false); mImageView = (ImageView) v.findViewById(R.id.picImageView); mProgressBar = (ProgressBar) v.findViewById(R.id.progressbar); return v; } @Override public void onActivityCreated(Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); // Use the parent activity to load the image asynchronously into the ImageView (so a single // cache can be used over all pages in the ViewPager if (ImageDetailActivity.class.isInstance(getActivity())) { mImageFetcher = ((ImageDetailActivity) getActivity()).getImageFetcher(); mImageFetcher.loadImage(mImageUrl, mIsLocal, mImageView, this); } } @Override public void onDestroy() { super.onDestroy(); if (mImageView != null) { // Cancel any pending image work ImageWorker.cancelWork(mImageView); mImageView.setImageDrawable(null); } } @Override public void onImageLoaded(boolean success) { // Set loading spinner to gone once image has loaded. Cloud also show // an error view here if needed. mProgressBar.setVisibility(View.GONE); } }