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 com.simplelife.seeds.android.utils.gridview.gridviewui; import android.annotation.SuppressLint; import android.annotation.TargetApi; import android.app.ActionBar; import android.app.ActivityOptions; import android.app.ProgressDialog; import android.content.Context; import android.content.Intent; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.support.v4.app.Fragment; import android.util.Log; import android.util.TypedValue; import android.view.Gravity; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.view.ViewGroup.LayoutParams; import android.view.ViewTreeObserver; import android.widget.AbsListView; import android.widget.AdapterView; import android.widget.BaseAdapter; import android.widget.GridView; import android.widget.ImageView; import android.widget.TextView; import android.widget.Toast; import com.simplelife.seeds.android.utils.dbprocess.SeedsDBAdapter; import com.simplelife.seeds.android.utils.downloadprocess.DownloadManager; import com.simplelife.seeds.android.utils.downloadprocess.ui.DownloadList; import com.simplelife.seeds.android.utils.gridview.gridviewprovider.Images; import com.simplelife.seeds.android.utils.gridview.gridviewui.ImageDetailActivity; import com.simplelife.seeds.android.BuildConfig; import com.simplelife.seeds.android.R; import com.simplelife.seeds.android.SeedsDateManager; import com.simplelife.seeds.android.SeedsDefinitions; import com.simplelife.seeds.android.SeedsPullToRefreshView; import com.simplelife.seeds.android.SeedsPullToRefreshView.OnHeaderRefreshListener; import com.simplelife.seeds.android.SeedsRSSCartActivity; import com.simplelife.seeds.android.SeedsRSSCartActivity.SeedsRSSList; import com.simplelife.seeds.android.utils.gridview.gridviewutil.ImageCache.ImageCacheParams; import com.simplelife.seeds.android.utils.gridview.gridviewutil.ImageFetcher; import com.simplelife.seeds.android.utils.gridview.gridviewutil.Utils; /** * The main fragment that powers the ImageGridActivity screen. Fairly straight forward GridView * implementation with the key addition being the ImageWorker class w/ImageCache to load children * asynchronously, keeping the UI nice and smooth and caching thumbnails for quick retrieval. The * cache is retained over configuration changes like orientation change so the images are populated * quickly if, for example, the user rotates the device. */ public class ImageGridFragment extends Fragment implements AdapterView.OnItemClickListener, OnHeaderRefreshListener { private static final String TAG = "ImageGridFragment"; //private static final String IMAGE_CACHE_DIR = "thumbs"; private int mImageThumbSize; private int mImageThumbSpacing; private ImageAdapter mAdapter; private ImageFetcher mImageFetcher; private SeedsPullToRefreshView mPullToRefreshView; // The menuItem favorite private MenuItem mFavItem = null; // Favorite tag private boolean mFavTag = false; // Seed local id private int mSeedLocalId = Images.getSeedLocalId(); // Database adapter private SeedsDBAdapter mDBAdapter; /** * Empty constructor as per the Fragment documentation */ public ImageGridFragment() { } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setHasOptionsMenu(true); mImageThumbSize = getResources().getDimensionPixelSize(R.dimen.image_thumbnail_size); mImageThumbSpacing = getResources().getDimensionPixelSize(R.dimen.image_thumbnail_spacing); mAdapter = new ImageAdapter(getActivity()); // Retrieve the adapter instance mDBAdapter = SeedsDBAdapter.getAdapter(getActivity()); ImageCacheParams cacheParams = new ImageCacheParams(getActivity(), SeedsDefinitions.SEEDS_THUMBS_CACHE_DIR); cacheParams.setMemCacheSizePercent(0.25f); // Set memory cache to 25% of app memory // The ImageFetcher takes care of loading images into our ImageView children asynchronously mImageFetcher = new ImageFetcher(getActivity(), mImageThumbSize); mImageFetcher.setLoadingImage(R.drawable.empty_photo); mImageFetcher.addImageCache(getActivity().getSupportFragmentManager(), cacheParams, "GRIDTAG"); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { final View v = inflater.inflate(R.layout.activity_seeds_gridview_gridfragment, container, false); final GridView mGridView = (GridView) v.findViewById(R.id.gridView); mPullToRefreshView = (SeedsPullToRefreshView) v.findViewById(R.id.main_pull_refresh_view_grid); mGridView.setAdapter(mAdapter); mGridView.setOnItemClickListener(this); mPullToRefreshView.setOnHeaderRefreshListener(this); mGridView.setOnScrollListener(new AbsListView.OnScrollListener() { @Override public void onScrollStateChanged(AbsListView absListView, int scrollState) { // Pause fetcher to ensure smoother scrolling when flinging if (scrollState == AbsListView.OnScrollListener.SCROLL_STATE_FLING) { mImageFetcher.setPauseWork(true); } else { mImageFetcher.setPauseWork(false); } } @Override public void onScroll(AbsListView absListView, int firstVisibleItem, int visibleItemCount, int totalItemCount) { } }); // This listener is used to get the final width of the GridView and then calculate the // number of columns and the width of each column. The width of each column is variable // as the GridView has stretchMode=columnWidth. The column width is used to set the height // of each view so we get nice square thumbnails. mGridView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() { @Override public void onGlobalLayout() { if (mAdapter.getNumColumns() == 0) { final int numColumns = (int) Math .floor(mGridView.getWidth() / (mImageThumbSize + mImageThumbSpacing)); if (numColumns > 0) { final int columnWidth = (mGridView.getWidth() / numColumns) - mImageThumbSpacing; mAdapter.setNumColumns(numColumns); mAdapter.setItemHeight(columnWidth); if (BuildConfig.DEBUG) { Log.d(TAG, "onCreateView - numColumns set to " + numColumns); } } } } }); // Set a title for this page ActionBar tActionBar = getActivity().getActionBar(); tActionBar.setTitle(R.string.seeds_details_top); // Show the details info of the seed // Prepare the seeds text info String tSeedName = Images.getSeedsEntity().getSeedName(); String tSeedSize = Images.getSeedsEntity().getSeedSize(); String tSeedFormat = Images.getSeedsEntity().getSeedFormat(); String tSeedMosaic = (Images.getSeedsEntity().getSeedMosaic()) ? getString(R.string.seeds_listperday_withmosaic) : getString(R.string.seeds_listperday_withoutmosaic); TextView tTextViewName = (TextView) v.findViewById(R.id.seed_grid_info_name); TextView tTextViewFormat = (TextView) v.findViewById(R.id.seed_grid_info_format); TextView tTextViewSize = (TextView) v.findViewById(R.id.seed_grid_info_size); TextView tTextViewMosaic = (TextView) v.findViewById(R.id.seed_grid_info_mosaic); if (null != tSeedName) tTextViewName.setText(getString(R.string.seedTitle) + ": " + tSeedName); if (null != tSeedFormat) tTextViewFormat.setText(getString(R.string.seedFormat) + ": " + tSeedFormat); if (null != tSeedSize) tTextViewSize.setText(getString(R.string.seedSize) + ": " + tSeedSize); if (null != tSeedMosaic) tTextViewMosaic.setText(getString(R.string.seeds_listperday_mosaic) + ": " + tSeedMosaic); return v; } @Override public void onHeaderRefresh(SeedsPullToRefreshView view) { mPullToRefreshView.postDelayed(new Runnable() { @Override public void run() { SeedsDateManager tDateMgr = SeedsDateManager.getDateManager(); mPullToRefreshView.onHeaderRefreshComplete( getString(R.string.pull_to_refresh_footer_refreshing_date) + tDateMgr.getRealTimeNow2()); //mPullToRefreshView.onHeaderRefreshComplete(); } }, 1000); } @Override public void onResume() { super.onResume(); mImageFetcher.setExitTasksEarly(false); mAdapter.notifyDataSetChanged(); } @Override public void onPause() { super.onPause(); mImageFetcher.setPauseWork(false); mImageFetcher.setExitTasksEarly(true); mImageFetcher.flushCache(); } @Override public void onDestroy() { super.onDestroy(); mImageFetcher.closeCache(); } @TargetApi(16) @Override public void onItemClick(AdapterView<?> parent, View v, int position, long id) { final Intent i = new Intent(getActivity(), ImageDetailActivity.class); i.putExtra(ImageDetailActivity.EXTRA_IMAGE, (int) id); if (Utils.hasJellyBean()) { // makeThumbnailScaleUpAnimation() looks kind of ugly here as the loading spinner may // show plus the thumbnail image in GridView is cropped. so using // makeScaleUpAnimation() instead. ActivityOptions options = ActivityOptions.makeScaleUpAnimation(v, 0, 0, v.getWidth(), v.getHeight()); getActivity().startActivity(i, options.toBundle()); } else { startActivity(i); } } private void addOrCancelFromFavList(MenuItem item) { if (mDBAdapter.isSeedSaveToFavorite(mSeedLocalId)) { mFavTag = true; } else { mFavTag = false; } // Set up a thread to operate with the database new Thread() { @Override public void run() { try { // Get the DB adapter instance SeedsDBAdapter mDBAdapter = SeedsDBAdapter.getAdapter(getActivity()); // Set the favorite key if (mFavTag) { mDBAdapter.updateSeedEntryFav(mSeedLocalId, false); mFavTag = false; ProgressDialog.show(getActivity(), "Cancelling Favorites...", "Done!", true, false); } else { mDBAdapter.updateSeedEntryFav(mSeedLocalId, true); mFavTag = true; ProgressDialog.show(getActivity(), "Adding to Favorites...", "Done!", true, false); } } catch (Exception e) { // Show the error message here } Message t_MsgListData = new Message(); t_MsgListData.what = 1; handler.sendMessage(t_MsgListData); } }.start(); } // Define a handler to process the progress update @SuppressLint("HandlerLeak") private Handler handler = new Handler() { @Override public void handleMessage(Message msg) { switch (msg.what) { case 1: // Check if this seed has already been saved to favorite if (mDBAdapter.isSeedSaveToFavorite(mSeedLocalId)) { if (null != mFavItem) mFavItem.setIcon(R.drawable.rating_not_important_large); Toast toast = Toast.makeText(getActivity(), R.string.seeds_fav_done, Toast.LENGTH_SHORT); toast.setGravity(Gravity.CENTER, 0, 0); toast.show(); } else { if (null != mFavItem) mFavItem.setIcon(R.drawable.rating_important_large); Toast toast = Toast.makeText(getActivity(), R.string.seeds_unfav_done, Toast.LENGTH_SHORT); toast.setGravity(Gravity.CENTER, 0, 0); toast.show(); } break; // Or try something here } } }; @Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { inflater.inflate(R.menu.activity_seeds_gridview_menu, menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case R.id.menu_addto_fav: { mFavItem = item; addOrCancelFromFavList(item); return true; } case R.id.rss_addtocart: { int tShowId; if (!SeedsRSSList.addSeedToCart(mSeedLocalId)) tShowId = R.string.seeds_rss_toast_addtocartnonecc; else tShowId = R.string.seeds_rss_toast_addtocartdone; Toast toast = Toast.makeText(getActivity(), tShowId, Toast.LENGTH_SHORT); toast.setGravity(Gravity.CENTER, 0, 0); toast.show(); return true; } case R.id.rss_management: { Intent intent = new Intent(getActivity(), SeedsRSSCartActivity.class); startActivity(intent); return true; } case R.id.download_seed: { // Fetch the download manager to start the download DownloadManager tDownloadMgr = DownloadManager.getDownloadMgr(getActivity().getContentResolver(), getActivity().getPackageName()); tDownloadMgr.startDownload(Images.getSeedsEntity().getSeedTorrentLink(), Images.getSeedsEntity().getSeedPublishDate(), Images.getSeedsEntity().getSeedName()); Toast toast = Toast.makeText(getActivity(), R.string.seeds_download_added, Toast.LENGTH_SHORT); toast.setGravity(Gravity.CENTER, 0, 0); toast.show(); return true; } case R.id.download_mgt: { Intent intent = new Intent(getActivity(), DownloadList.class); startActivity(intent); return true; } case R.id.clear_cache: { mImageFetcher.clearCache(); Toast.makeText(getActivity(), R.string.clear_cache_complete_toast, Toast.LENGTH_SHORT).show(); return true; } } return true; } /** * The main adapter that backs the GridView. This is fairly standard except the number of * columns in the GridView is used to create a fake top row of empty views as we use a * transparent ActionBar and don't want the real top row of images to start off covered by it. */ private class ImageAdapter extends BaseAdapter { private final Context mContext; private int mItemHeight = 0; private int mNumColumns = 0; private int mActionBarHeight = 0; private GridView.LayoutParams mImageViewLayoutParams; public ImageAdapter(Context context) { super(); mContext = context; mImageViewLayoutParams = new GridView.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT); // Calculate ActionBar height TypedValue tv = new TypedValue(); if (context.getTheme().resolveAttribute(android.R.attr.actionBarSize, tv, true)) { /*mActionBarHeight = TypedValue.complexToDimensionPixelSize( tv.data, context.getResources().getDisplayMetrics());*/ } } @Override public int getCount() { // Size + number of columns for top empty row //return Images.imageThumbUrls.length + mNumColumns; return Images.getSeedsEntity().getPicLinks().size() + mNumColumns; } @Override public Object getItem(int position) { return position < mNumColumns ? null : Images.getSeedsEntity().getPicLinks().get(position - mNumColumns); } @Override public long getItemId(int position) { return position < mNumColumns ? 0 : position - mNumColumns; } @Override public int getViewTypeCount() { // Two types of views, the normal ImageView and the top row of empty views return 2; } @Override public int getItemViewType(int position) { return (position < mNumColumns) ? 1 : 0; } @Override public boolean hasStableIds() { return true; } @Override public View getView(int position, View convertView, ViewGroup container) { // First check if this is the top row if (position < mNumColumns) { if (convertView == null) { convertView = new View(mContext); } // Set empty view with height of ActionBar convertView.setLayoutParams( new AbsListView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, mActionBarHeight)); return convertView; } // Now handle the main ImageView thumbnails ImageView imageView; if (convertView == null) { // if it's not recycled, instantiate and initialize imageView = new RecyclingImageView(mContext); imageView.setScaleType(ImageView.ScaleType.CENTER_CROP); imageView.setLayoutParams(mImageViewLayoutParams); } else { // Otherwise re-use the converted view imageView = (ImageView) convertView; } // Check the height matches our calculated column width if (imageView.getLayoutParams().height != mItemHeight) { imageView.setLayoutParams(mImageViewLayoutParams); } // Finally load the image asynchronously into the ImageView, this also takes care of // setting a placeholder image while the background thread runs //mImageFetcher.loadImage(Images.imageThumbUrls[position - mNumColumns], imageView); mImageFetcher.loadImage(Images.getSeedsEntity().getPicLinks().get(position - mNumColumns), imageView); return imageView; } /** * Sets the item height. Useful for when we know the column width so the height can be set * to match. * * @param height */ public void setItemHeight(int height) { if (height == mItemHeight) { return; } mItemHeight = height; mImageViewLayoutParams = new GridView.LayoutParams(LayoutParams.MATCH_PARENT, mItemHeight); mImageFetcher.setImageSize(height); notifyDataSetChanged(); } public void setNumColumns(int numColumns) { mNumColumns = numColumns; } public int getNumColumns() { return mNumColumns; } } }