Java tutorial
/* * ****************************************************************************** * Copyright (c) 2013 Gabriele Mariotti. * * 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 it.gmariotti.cardslib.library.view.component; import android.content.Context; import android.content.Intent; import android.content.res.Resources; import android.content.res.TypedArray; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.drawable.BitmapDrawable; import android.graphics.drawable.Drawable; import android.os.AsyncTask; import android.os.Build; import android.util.AttributeSet; import android.util.Log; import android.support.v4.util.LruCache; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.FrameLayout; import android.widget.ImageView; import java.io.IOException; import java.lang.ref.WeakReference; import java.net.URL; import it.gmariotti.cardslib.library.Constants; import it.gmariotti.cardslib.library.internal.CardThumbnail; import it.gmariotti.cardslib.library.utils.CacheUtil; import it.gmariotti.cardslib.library.view.base.CardViewInterface; import it.gmariotti.cardslib.library.R; /** * Compound View for Thumbnail Component. * </p> * It is built with base_thumbnail_layout.xml. * </p> * Please note that this is currently in a preview state. * This means that the API is not fixed and you should expect changes between releases. * </p> * This class load a bitmap resource using {@link android.util.LruCache} and using an * AsyncTask to prevent UI blocks. * * @author Gabriele Mariotti (gabri.mariotti@gmail.com) */ public class CardThumbnailView extends FrameLayout implements CardViewInterface { //-------------------------------------------------------------------------- // Custom Attrs //-------------------------------------------------------------------------- /** * Default Layout for Thumbnail View */ protected int card_thumbnail_layout_resourceID = R.layout.base_thumbnail_layout; /** Global View for this Component */ protected View mInternalOuterView; /** * CardThumbnail model */ protected CardThumbnail mCardThumbnail; /** * Memory Cache */ protected LruCache<String, Bitmap> mMemoryCache; /** * Used to recycle ui elements. */ protected boolean mIsRecycle = false; /** * Used to replace inner layout elements. */ protected boolean mForceReplaceInnerLayout = false; protected boolean mLoadingErrorResource = false; //-------------------------------------------------------------------------- // Constructors //-------------------------------------------------------------------------- public CardThumbnailView(Context context) { super(context); init(null, 0); } public CardThumbnailView(Context context, AttributeSet attrs) { super(context, attrs); init(attrs, 0); } public CardThumbnailView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); init(attrs, defStyle); } //-------------------------------------------------------------------------- // View //-------------------------------------------------------------------------- /** * ImageView inside CardThumbnail */ protected ImageView mImageView; //-------------------------------------------------------------------------- // Init //-------------------------------------------------------------------------- /** * Initialize * * @param attrs * @param defStyle */ protected void init(AttributeSet attrs, int defStyle) { //Init attrs initAttrs(attrs, defStyle); //Init View if (!isInEditMode()) initView(); } /** * Init custom attrs. * * @param attrs * @param defStyle */ protected void initAttrs(AttributeSet attrs, int defStyle) { TypedArray a = getContext().getTheme().obtainStyledAttributes(attrs, R.styleable.card_options, defStyle, defStyle); try { card_thumbnail_layout_resourceID = a.getResourceId( R.styleable.card_options_card_thumbnail_layout_resourceID, card_thumbnail_layout_resourceID); } finally { a.recycle(); } } /** * Init view */ protected void initView() { LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE); mInternalOuterView = inflater.inflate(card_thumbnail_layout_resourceID, this, true); //Get ImageVIew mImageView = (ImageView) findViewById(R.id.card_thumbnail_image); // Get max available VM memory, exceeding this amount will throw an // OutOfMemory exception. Stored in kilobytes as LruCache takes an // int in its constructor. final int maxMemory = (int) (Runtime.getRuntime().maxMemory() / 1024); // Use 1/8th of the available memory for this memory cache. final int cacheSize = maxMemory / 8; mMemoryCache = CacheUtil.getMemoryCache(); if (mMemoryCache == null) { mMemoryCache = new LruCache<String, Bitmap>(cacheSize) { @Override protected int sizeOf(String key, Bitmap bitmap) { // The cache size will be measured in kilobytes rather than // number of items. if (Build.VERSION.SDK_INT > Build.VERSION_CODES.HONEYCOMB_MR1) { return bitmap.getByteCount() / 1024; } else { return bitmap.getRowBytes() * bitmap.getHeight() / 1024; } } }; CacheUtil.putMemoryCache(mMemoryCache); } } //-------------------------------------------------------------------------- // Add Thumbnail //-------------------------------------------------------------------------- /** * Adds a {@link CardThumbnail}. * It is important to set all thumbnail values before launch this method. * * @param cardThumbail thumbnail model */ public void addCardThumbnail(CardThumbnail cardThumbail) { mCardThumbnail = cardThumbail; buildUI(); } /** * Refresh UI */ protected void buildUI() { if (mCardThumbnail == null) return; if (mIsRecycle) mLoadingErrorResource = false; //Setup InnerView setupInnerView(); } /** * Sets the inner view. * */ protected void setupInnerView() { //Setup Elements before load image if (mInternalOuterView != null) mCardThumbnail.setupInnerViewElements((ViewGroup) mInternalOuterView, mImageView); //Load bitmap if (!mCardThumbnail.isExternalUsage()) { if (mCardThumbnail.getCustomSource() != null) loadBitmap(mCardThumbnail.getCustomSource(), mImageView); else if (mCardThumbnail.getDrawableResource() > 0) loadBitmap(mCardThumbnail.getDrawableResource(), mImageView); else loadBitmap(mCardThumbnail.getUrlResource(), mImageView); } } //-------------------------------------------------------------------------- // Load Bitmap and cache manage //-------------------------------------------------------------------------- public void loadBitmap(int resId, ImageView imageView) { final String imageKey = String.valueOf(resId); final Bitmap bitmap = getBitmapFromMemCache(imageKey); if (bitmap != null) { if (!mCardThumbnail.applyBitmap(imageView, bitmap)) imageView.setImageBitmap(bitmap); sendBroadcast(); } else { if (cancelPotentialWork(resId, imageView)) { final BitmapWorkerTask task = new BitmapWorkerTask(imageView); final AsyncDrawable asyncDrawable = new AsyncDrawable(getResources(), null, task); imageView.setImageDrawable(asyncDrawable); task.execute(resId); } } } public void loadBitmap(String url, ImageView imageView) { final String imageKey = url; final Bitmap bitmap = getBitmapFromMemCache(imageKey); if (bitmap != null) { if (!mCardThumbnail.applyBitmap(imageView, bitmap)) imageView.setImageBitmap(bitmap); sendBroadcast(); } else { if (cancelPotentialWork(url, imageView)) { final BitmapWorkerUrlTask task = new BitmapWorkerUrlTask(imageView); final AsyncDrawableUrl asyncDrawable = new AsyncDrawableUrl(getResources(), null, task); imageView.setImageDrawable(asyncDrawable); task.execute(url); } } } public void loadBitmap(CardThumbnail.CustomSource customSource, ImageView imageView) { final String imageKey = customSource.getTag(); final Bitmap bitmap = getBitmapFromMemCache(imageKey); if (bitmap != null) { if (!mCardThumbnail.applyBitmap(imageView, bitmap)) imageView.setImageBitmap(bitmap); sendBroadcast(); } else { if (cancelPotentialWork(customSource, imageView)) { final BitmapWorkerCustomSourceTask task = new BitmapWorkerCustomSourceTask(imageView); final AsyncDrawableCustomSource asyncDrawable = new AsyncDrawableCustomSource(getResources(), null, task); imageView.setImageDrawable(asyncDrawable); task.execute(customSource); } } } protected void addBitmapToMemoryCache(String key, Bitmap bitmap) { if (!mLoadingErrorResource && getBitmapFromMemCache(key) == null) { if (key != null && bitmap != null) { mMemoryCache.put(key, bitmap); } } } protected Bitmap getBitmapFromMemCache(String key) { if (key == null) return null; return mMemoryCache.get(key); } public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId, int reqWidth, int reqHeight) { // First decode with inJustDecodeBounds=true to check dimensions final BitmapFactory.Options options = new BitmapFactory.Options(); options.inJustDecodeBounds = true; BitmapFactory.decodeResource(res, resId, options); // Calculate inSampleSize options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight); // Decode bitmap with inSampleSize set options.inJustDecodeBounds = false; return BitmapFactory.decodeResource(res, resId, options); } public static Bitmap decodeSampledBitmapFromResource(Resources res, String resUrl, int reqWidth, int reqHeight) { try { // First decode with inJustDecodeBounds=true to check dimensions final BitmapFactory.Options options = new BitmapFactory.Options(); options.inJustDecodeBounds = true; //BitmapFactory.decodeResource(res, resId, options); BitmapFactory.decodeStream(new URL(resUrl).openStream()); // Calculate inSampleSize options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight); // Decode bitmap with inSampleSize set options.inJustDecodeBounds = false; return BitmapFactory.decodeStream(new URL(resUrl).openStream()); } catch (IOException ioe) { //Url not available //ioe.printStackTrace(); Log.w("CardThumbnailView", "Error while retrieving image", ioe); } return null; } public static int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) { // Raw height and width of image final int height = options.outHeight; final int width = options.outWidth; int inSampleSize = 1; if (reqWidth == 0 || reqHeight == 0) return inSampleSize; if (height > reqHeight || width > reqWidth) { // Calculate ratios of height and width to requested height and width final int heightRatio = Math.round((float) height / (float) reqHeight); final int widthRatio = Math.round((float) width / (float) reqWidth); // Choose the smallest ratio as inSampleSize value, this will guarantee // a final image with both dimensions larger than or equal to the // requested height and width. inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio; } return inSampleSize; } //-------------------------------------------------------------------------- // Worker //-------------------------------------------------------------------------- public static boolean cancelPotentialWork(int resId, ImageView imageView) { final BitmapWorkerTask bitmapWorkerTask = getBitmapWorkerTask(imageView); if (bitmapWorkerTask != null) { final int bitmapWorkerTaskResId = bitmapWorkerTask.resId; if (bitmapWorkerTaskResId != resId) { // Cancel previous task bitmapWorkerTask.cancel(true); } else { // The same work is already in progress return false; } } // No task associated with the ImageView, or an existing task was cancelled return true; } public static boolean cancelPotentialWork(String url, ImageView imageView) { final BitmapWorkerUrlTask bitmapWorkerTask = getBitmapWorkerUrlTask(imageView); if (bitmapWorkerTask != null) { final String bitmapWorkerTaskResUrl = bitmapWorkerTask.resUrl; if (!bitmapWorkerTaskResUrl.equals(url)) { // Cancel previous task bitmapWorkerTask.cancel(true); } else { // The same work is already in progress return false; } } // No task associated with the ImageView, or an existing task was cancelled return true; } public static boolean cancelPotentialWork(CardThumbnail.CustomSource customSource, ImageView imageView) { final BitmapWorkerCustomSourceTask bitmapWorkerTask = getBitmapWorkerCustomSourceTask(imageView); if (bitmapWorkerTask != null) { final CardThumbnail.CustomSource bitmapWorkerTaskCustomSource = bitmapWorkerTask.customSource; if (!bitmapWorkerTaskCustomSource.getTag().equals(customSource.getTag())) { // Cancel previous task bitmapWorkerTask.cancel(true); } else { // The same work is already in progress return false; } } // No task associated with the ImageView, or an existing task was cancelled return true; } protected static BitmapWorkerTask getBitmapWorkerTask(ImageView imageView) { if (imageView != null) { final Drawable drawable = imageView.getDrawable(); if (drawable instanceof AsyncDrawable) { final AsyncDrawable asyncDrawable = (AsyncDrawable) drawable; return asyncDrawable.getBitmapWorkerTask(); } } return null; } protected static BitmapWorkerUrlTask getBitmapWorkerUrlTask(ImageView imageView) { if (imageView != null) { final Drawable drawable = imageView.getDrawable(); if (drawable instanceof AsyncDrawableUrl) { final AsyncDrawableUrl asyncDrawable = (AsyncDrawableUrl) drawable; return asyncDrawable.getBitmapWorkerUrlTask(); } } return null; } protected static BitmapWorkerCustomSourceTask getBitmapWorkerCustomSourceTask(ImageView imageView) { if (imageView != null) { final Drawable drawable = imageView.getDrawable(); if (drawable instanceof AsyncDrawableCustomSource) { final AsyncDrawableCustomSource asyncDrawable = (AsyncDrawableCustomSource) drawable; return asyncDrawable.getBitmapWorkerCustomSourceTask(); } } return null; } class BitmapWorkerTask extends AsyncTask<Integer, Void, Bitmap> { private final WeakReference<ImageView> imageViewReference; private int resId = 0; public BitmapWorkerTask(ImageView imageView) { // Use a WeakReference to ensure the ImageView can be garbage collected imageViewReference = new WeakReference<ImageView>(imageView); } // Decode image in background. @Override protected Bitmap doInBackground(Integer... params) { resId = params[0]; ImageView thumbnail = imageViewReference.get(); Bitmap bitmap = decodeSampledBitmapFromResource(getResources(), resId, thumbnail.getWidth(), thumbnail.getHeight()); if (bitmap != null) { addBitmapToMemoryCache(String.valueOf(params[0]), bitmap); return bitmap; } else { return (Bitmap) null; } } // Once complete, see if ImageView is still around and set bitmap. @Override protected void onPostExecute(Bitmap bitmap) { if (isCancelled()) { bitmap = null; } if (imageViewReference != null && bitmap != null) { final ImageView imageView = imageViewReference.get(); final BitmapWorkerTask bitmapWorkerTask = getBitmapWorkerTask(imageView); if (this == bitmapWorkerTask && imageView != null) { if (!mCardThumbnail.applyBitmap(imageView, bitmap)) imageView.setImageBitmap(bitmap); sendBroadcast(); mLoadingErrorResource = false; } } else { sendBroadcast(false); if (mCardThumbnail != null && mCardThumbnail.getErrorResourceId() != 0) { if (!mLoadingErrorResource) { //To avoid a loop loadBitmap(mCardThumbnail.getErrorResourceId(), mImageView); } mLoadingErrorResource = true; } } } } class BitmapWorkerUrlTask extends AsyncTask<String, Void, Bitmap> { private final WeakReference<ImageView> imageViewReference; private String resUrl = ""; public BitmapWorkerUrlTask(ImageView imageView) { // Use a WeakReference to ensure the ImageView can be garbage collected imageViewReference = new WeakReference<ImageView>(imageView); } // Decode image in background. @Override protected Bitmap doInBackground(String... params) { resUrl = params[0]; ImageView thumbnail = imageViewReference.get(); Bitmap bitmap = decodeSampledBitmapFromResource(getResources(), resUrl, thumbnail.getWidth(), thumbnail.getHeight()); if (bitmap != null) { addBitmapToMemoryCache(String.valueOf(params[0]), bitmap); return bitmap; } else return (Bitmap) null; } // Once complete, see if ImageView is still around and set bitmap. @Override protected void onPostExecute(Bitmap bitmap) { if (isCancelled()) { bitmap = null; } if (imageViewReference != null && bitmap != null) { final ImageView imageView = imageViewReference.get(); final BitmapWorkerUrlTask bitmapWorkerTask = getBitmapWorkerUrlTask(imageView); if (this == bitmapWorkerTask && imageView != null) { if (!mCardThumbnail.applyBitmap(imageView, bitmap)) imageView.setImageBitmap(bitmap); sendBroadcast(); mLoadingErrorResource = false; } } else { sendBroadcast(false); if (mCardThumbnail != null && mCardThumbnail.getErrorResourceId() != 0) { if (!mLoadingErrorResource) { //To avoid a loop loadBitmap(mCardThumbnail.getErrorResourceId(), mImageView); } mLoadingErrorResource = true; } } } } class BitmapWorkerCustomSourceTask extends AsyncTask<CardThumbnail.CustomSource, Void, Bitmap> { private final WeakReference<ImageView> imageViewReference; private CardThumbnail.CustomSource customSource = null; public BitmapWorkerCustomSourceTask(ImageView imageView) { // Use a WeakReference to ensure the ImageView can be garbage collected imageViewReference = new WeakReference<ImageView>(imageView); } // Decode image in background. @Override protected Bitmap doInBackground(CardThumbnail.CustomSource... params) { customSource = params[0]; ImageView thumbnail = imageViewReference.get(); Bitmap bitmap = customSource.getBitmap(); if (bitmap != null) { addBitmapToMemoryCache(customSource.getTag(), bitmap); return bitmap; } else { return (Bitmap) null; } } // Once complete, see if ImageView is still around and set bitmap. @Override protected void onPostExecute(Bitmap bitmap) { if (isCancelled()) { bitmap = null; } if (imageViewReference != null && bitmap != null) { final ImageView imageView = imageViewReference.get(); final BitmapWorkerCustomSourceTask bitmapWorkerTask = getBitmapWorkerCustomSourceTask(imageView); if (this == bitmapWorkerTask && imageView != null) { if (!mCardThumbnail.applyBitmap(imageView, bitmap)) imageView.setImageBitmap(bitmap); sendBroadcast(); mLoadingErrorResource = false; } } else { sendBroadcast(false); if (mCardThumbnail != null && mCardThumbnail.getErrorResourceId() != 0) { if (!mLoadingErrorResource) { //To avoid a loop loadBitmap(mCardThumbnail.getErrorResourceId(), mImageView); } mLoadingErrorResource = true; } } } } static class AsyncDrawable extends BitmapDrawable { private final WeakReference<BitmapWorkerTask> bitmapWorkerTaskReference; public AsyncDrawable(Resources res, Bitmap bitmap, BitmapWorkerTask bitmapWorkerTask) { super(res, bitmap); bitmapWorkerTaskReference = new WeakReference<BitmapWorkerTask>(bitmapWorkerTask); } public BitmapWorkerTask getBitmapWorkerTask() { return bitmapWorkerTaskReference.get(); } } static class AsyncDrawableUrl extends BitmapDrawable { private final WeakReference<BitmapWorkerUrlTask> bitmapWorkerTaskReference; public AsyncDrawableUrl(Resources res, Bitmap bitmap, BitmapWorkerUrlTask bitmapWorkerTask) { super(res, bitmap); bitmapWorkerTaskReference = new WeakReference<BitmapWorkerUrlTask>(bitmapWorkerTask); } public BitmapWorkerUrlTask getBitmapWorkerUrlTask() { return bitmapWorkerTaskReference.get(); } } static class AsyncDrawableCustomSource extends BitmapDrawable { private final WeakReference<BitmapWorkerCustomSourceTask> bitmapWorkerTaskReference; public AsyncDrawableCustomSource(Resources res, Bitmap bitmap, BitmapWorkerCustomSourceTask bitmapWorkerTask) { super(res, bitmap); bitmapWorkerTaskReference = new WeakReference<BitmapWorkerCustomSourceTask>(bitmapWorkerTask); } public BitmapWorkerCustomSourceTask getBitmapWorkerCustomSourceTask() { return bitmapWorkerTaskReference.get(); } } //-------------------------------------------------------------------------- // Broadcast //-------------------------------------------------------------------------- /** * Send a successful broadcast when image is downloaded */ protected void sendBroadcast() { sendBroadcast(true); } /** * Send a broadcast when image is downloaded * * @param result */ protected void sendBroadcast(boolean result) { Intent intent = new Intent(); intent.setAction(Constants.IntentManager.INTENT_ACTION_IMAGE_DOWNLOADED); intent.putExtra(Constants.IntentManager.INTENT_ACTION_IMAGE_DOWNLOADED_EXTRA_RESULT, result); if (mLoadingErrorResource) intent.putExtra(Constants.IntentManager.INTENT_ACTION_IMAGE_DOWNLOADED_EXTRA_ERROR_LOADING, true); else intent.putExtra(Constants.IntentManager.INTENT_ACTION_IMAGE_DOWNLOADED_EXTRA_ERROR_LOADING, false); if (mCardThumbnail != null && mCardThumbnail.getParentCard() != null) intent.putExtra(Constants.IntentManager.INTENT_ACTION_IMAGE_DOWNLOADED_EXTRA_CARD_ID, mCardThumbnail.getParentCard().getId()); if (getContext() != null) getContext().sendBroadcast(intent); } //-------------------------------------------------------------------------- // Getters and Setters //-------------------------------------------------------------------------- @Override public View getInternalOuterView() { return null; } /** * Indicates if view can recycle ui elements. * * @return <code>true</code> if views can recycle ui elements */ public boolean isRecycle() { return mIsRecycle; } /** * Sets if view can recycle ui elements * * @param isRecycle <code>true</code> to recycle */ public void setRecycle(boolean isRecycle) { this.mIsRecycle = isRecycle; } /** * Indicates if inner layout have to be replaced * * @return <code>true</code> if inner layout can be recycled */ public boolean isForceReplaceInnerLayout() { return mForceReplaceInnerLayout; } /** * Sets if inner layout have to be replaced * * @param forceReplaceInnerLayout <code>true</code> to recycle */ public void setForceReplaceInnerLayout(boolean forceReplaceInnerLayout) { this.mForceReplaceInnerLayout = forceReplaceInnerLayout; } }