com.itsherpa.andg.imageloader.ImageWorker.java Source code

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/*
 * 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.itsherpa.andg.imageloader;

import glas.bbsystem.BuildConfig;

import java.lang.ref.WeakReference;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.widget.ImageView;

import com.itsherpa.andg.connection.request.CircleImageRequest;
import com.itsherpa.andg.constant.Constants;
import com.itsherpa.andg.util.LogUtils;
import com.itsherpa.andg.util.Utility;

/**
 * This class wraps up completing some arbitrary long running work when loading
 * a bitmap to an ImageView. It handles things like using a memory and disk
 * cache, running the work in a background thread and setting a placeholder
 * image.
 */
public abstract class ImageWorker {
    private static final String TAG = "ImageWorker";
    private static final int FADE_IN_TIME = 300;
    private static final int NO_GENDER = -1;

    private ImageCache mImageCache;
    private ImageCache.ImageCacheParams mImageCacheParams;
    private Bitmap mLoadingBitmap;
    private Bitmap mLoadingCircleBitmap;
    private Bitmap mLoadingMaleBitmap;
    private Bitmap mLoadingFemaleBitmap;
    private boolean mFadeInBitmap = true;
    private boolean mExitTasksEarly = false;
    protected boolean mPauseWork = false;
    private final Object mPauseWorkLock = new Object();
    protected Context mContext;

    protected Resources mResources;

    private static final int MESSAGE_CLEAR = 0;
    private static final int MESSAGE_INIT_DISK_CACHE = 1;
    private static final int MESSAGE_FLUSH = 2;
    private static final int MESSAGE_CLOSE = 3;

    public static interface ImageListener {
        public void onGetImageSuccess(Bitmap bitmap);

        public void onGetImageFailure();
    }

    protected ImageWorker(Context context) {
        mResources = context.getResources();
        mContext = context;
    }

    /**
     * Load image with default placeholder
     * 
     * @param data
     * @param imageView
     * @param size
     */
    public void loadImage(Object data, ImageView imageView, int size) {
        loadImage(data, imageView, size, size, NO_GENDER, true, null);
    }

    /**
     * 
     * @param data
     * @param imageView
     * @param size
     * @param imageListener
     */
    public void loadImage(Object data, ImageView imageView, int size, ImageListener imageListener) {
        loadImage(data, imageView, size, size, NO_GENDER, true, imageListener);
    }

    /**
     * Load image with default placeholder when loading
     * 
     * @param data
     * @param imageView
     * @param width
     * @param height
     */
    public void loadImage(Object data, ImageView imageView, int width, int height) {
        loadImage(data, imageView, width, height, NO_GENDER, true, null);
    }

    /**
     * 
     * @param data
     * @param imageView
     * @param width
     * @param height
     * @param imageListener
     */
    public void loadImage(Object data, ImageView imageView, int width, int height, ImageListener imageListener) {
        loadImage(data, imageView, width, height, NO_GENDER, true, imageListener);
    }

    /**
     * Load image without placholder (loading image) showed when loading
     * 
     * @param data
     * @param imageView
     * @param size
     */
    public void loadImageWithoutPlaceHolder(Object data, ImageView imageView, int size) {
        loadImage(data, imageView, size, size, NO_GENDER, false, null);
    }

    /**
     * 
     * @param data
     * @param imageView
     * @param size
     * @param imageListener
     */
    public void loadImageWithoutPlaceHolder(Object data, ImageView imageView, int size,
            ImageListener imageListener) {
        loadImage(data, imageView, size, size, NO_GENDER, false, imageListener);
    }

    /**
     * 
     * @param data
     * @param imageView
     * @param width
     * @param height
     */
    public void loadImageWithoutPlaceHolder(Object data, ImageView imageView, int width, int height) {
        loadImage(data, imageView, width, height, NO_GENDER, false, null);
    }

    /**
     * 
     * @param data
     * @param imageView
     * @param width
     * @param height
     * @param imageListener
     */
    public void loadImageWithoutPlaceHolder(Object data, ImageView imageView, int width, int height,
            ImageListener imageListener) {
        loadImage(data, imageView, width, height, NO_GENDER, false, imageListener);
    }

    /**
     * Load image with placeholder by gender, width=height
     * 
     * @param data
     * @param imageView
     * @param size
     * @param gender
     */
    public void loadImageByGender(Object data, ImageView imageView, int size, int gender) {
        loadImage(data, imageView, size, size, gender, true, null);
    }

    /**
     * 
     * @param data
     * @param imageView
     * @param size
     * @param gender
     * @param imageListener
     */
    public void loadImageByGender(Object data, ImageView imageView, int size, int gender,
            ImageListener imageListener) {
        loadImage(data, imageView, size, size, gender, true, imageListener);
    }

    /**
     * 
     * @param data
     * @param imageView
     * @param width
     * @param height
     * @param gender
     */
    public void loadImageByGender(Object data, ImageView imageView, int width, int height, int gender) {
        loadImage(data, imageView, width, height, gender, true, null);
    }

    /**
     * 
     * @param data
     * @param imageView
     * @param width
     * @param height
     * @param gender
     * @param imageListener
     */
    public void loadImageByGender(Object data, ImageView imageView, int width, int height, int gender,
            ImageListener imageListener) {
        loadImage(data, imageView, width, height, gender, true, imageListener);
    }

    private Bitmap getBitmapCover(boolean hasCover, int gender, boolean isCircle) {
        if (!hasCover)
            return null;
        Bitmap loadingBitmap;
        switch (gender) {
        case Constants.GENDER_TYPE_MAN:
            loadingBitmap = mLoadingMaleBitmap;
            break;
        case Constants.GENDER_TYPE_WOMAN:
            loadingBitmap = mLoadingFemaleBitmap;
            break;
        default:
            if (isCircle) {
                loadingBitmap = mLoadingCircleBitmap;
            } else {
                loadingBitmap = mLoadingBitmap;
            }
            break;
        }
        if (loadingBitmap != null && isCircle) {
            loadingBitmap = Utils.getBitmapInCircle(loadingBitmap);
        }
        return loadingBitmap;
    }

    /**
     * Load an image specified by the data parameter into an ImageView (override
     * {@link ImageWorker#processBitmap(Object)} to define the processing
     * logic). A memory and disk cache will be used if an {@link ImageCache} has
     * been added using
     * {@link ImageWorker#addImageCache(FragmentManager, ImageCache.ImageCacheParams)}
     * . If the image is found in the memory cache, it is set immediately,
     * otherwise an {@link AsyncTask} will be created to asynchronously load the
     * bitmap.
     * 
     * @param data
     *            The URL of the image to download.
     * @param imageView
     *            The ImageView to bind the downloaded image to.
     */
    private void loadImage(Object data, ImageView imageView, int width, int height, int gender, boolean hasCover,
            ImageListener imageListener) {

        if (data == null) {
            return;
        }
        BitmapDrawable value = null;
        if (mImageCache != null) {
            value = mImageCache.getBitmapFromMemCache(getCacheKeyFromObject(data));
        }
        boolean isCircle = false;
        if (data instanceof CircleImageRequest) {
            isCircle = true;
        }
        Bitmap loadingBitmap = getBitmapCover(hasCover, gender, isCircle);

        if (value != null) {
            // Bitmap found in memory cache
            Bitmap bitmap = value.getBitmap();
            if (isCircle) {
                bitmap = Utils.getBitmapInCircle(bitmap);
            }
            imageView.setImageBitmap(bitmap);
            if (imageListener != null)
                imageListener.onGetImageSuccess(value.getBitmap());
        } else if (cancelPotentialWork(data, imageView)) {
            final BitmapWorkerTask task = new BitmapWorkerTask(imageView, width, height, gender, hasCover, isCircle,
                    imageListener);

            final AsyncDrawable asyncDrawable = new AsyncDrawable(mResources, loadingBitmap, task);
            imageView.setImageDrawable(asyncDrawable);

            // NOTE: This uses a custom version of AsyncTask that has been
            // pulled from the
            // framework and slightly modified. Refer to the docs at the top of
            // the class
            // for more info on what was changed.
            task.executeOnExecutor(AsyncTask.DUAL_THREAD_EXECUTOR, data);
        }

    }

    /**
     * Set placeholder bitmap that shows when the the background thread is
     * running.
     * 
     * @param bitmap
     */
    public void setLoadingImage(Bitmap bitmap) {
        mLoadingBitmap = bitmap;
    }

    public void setLoadingImage(int resId) {
        mLoadingBitmap = BitmapFactory.decodeResource(mResources, resId);
    }

    public void setLoadingImage(int resIdMale, int resIdFemale) {
        mLoadingMaleBitmap = BitmapFactory.decodeResource(mResources, resIdMale);
        mLoadingFemaleBitmap = BitmapFactory.decodeResource(mResources, resIdFemale);
    }

    /**
     * Set placeholder circle bitmap that shows when the the background thread
     * is running.
     * 
     * @param bitmap
     */
    public void setLoadingCircleBitmap(Bitmap bitmap) {
        mLoadingCircleBitmap = bitmap;
    }

    public void setLoadingCircleBitmap(int resId) {
        mLoadingCircleBitmap = BitmapFactory.decodeResource(mResources, resId);
    }

    /**
     * Set placeholder bitmap that shows when the the background thread is
     * running.
     * 
     * @param resId
     */
    public void setLoadingImage(int resId, int resCircleId, int resIdMale, int resIdFemale) {
        mLoadingBitmap = BitmapFactory.decodeResource(mResources, resId);
        mLoadingCircleBitmap = BitmapFactory.decodeResource(mResources, resCircleId);
        mLoadingMaleBitmap = BitmapFactory.decodeResource(mResources, resIdMale);
        mLoadingFemaleBitmap = BitmapFactory.decodeResource(mResources, resIdFemale);
    }

    /**
     * Adds an {@link ImageCache} to this {@link ImageWorker} to handle disk and
     * memory bitmap caching.
     * 
     * @param fragmentManager
     * @param cacheParams
     *            The cache parameters to use for the image cache.
     */
    public void addImageCache(FragmentManager fragmentManager, ImageCache.ImageCacheParams cacheParams) {
        mImageCacheParams = cacheParams;
        mImageCache = ImageCache.getInstance(fragmentManager, mImageCacheParams);
        new CacheAsyncTask().execute(MESSAGE_INIT_DISK_CACHE);
    }

    /**
     * Adds an {@link ImageCache} to this {@link ImageWorker} to handle disk and
     * memory bitmap caching.
     * 
     * @param activity
     * @param diskCacheDirectoryName
     *            See
     *            {@link ImageCache.ImageCacheParams#ImageCacheParams(Context, String)}
     *            .
     */
    public void addImageCache(FragmentActivity activity, String diskCacheDirectoryName) {
        mImageCacheParams = new ImageCache.ImageCacheParams(activity, diskCacheDirectoryName);
        mImageCache = ImageCache.getInstance(activity.getSupportFragmentManager(), mImageCacheParams);
        new CacheAsyncTask().execute(MESSAGE_INIT_DISK_CACHE);
    }

    /**
     * If set to true, the image will fade-in once it has been loaded by the
     * background thread.
     */
    public void setImageFadeIn(boolean fadeIn) {
        mFadeInBitmap = fadeIn;
    }

    public void setExitTasksEarly(boolean exitTasksEarly) {
        mExitTasksEarly = exitTasksEarly;
        setPauseWork(false);
    }

    /**
     * Subclasses should override this to define any processing or work that
     * must happen to produce the final bitmap. This will be executed in a
     * background thread and be long running. For example, you could resize a
     * large bitmap here, or pull down an image from the network.
     * 
     * @param data
     *            The data to identify which image to process, as provided by
     *            {@link ImageWorker#loadImage(Object, ImageView)}
     * @return The processed bitmap
     */
    protected abstract Bitmap processBitmap(Object data, int width, int height);

    /**
     * @return The {@link ImageCache} object currently being used by this
     *         ImageWorker.
     */
    protected ImageCache getImageCache() {
        return mImageCache;
    }

    /**
     * Cancels any pending work attached to the provided ImageView.
     * 
     * @param imageView
     */
    public static void cancelWork(ImageView imageView) {
        final BitmapWorkerTask bitmapWorkerTask = getBitmapWorkerTask(imageView);
        if (bitmapWorkerTask != null) {
            bitmapWorkerTask.cancel(true);
            if (BuildConfig.DEBUG) {
                final Object bitmapData = bitmapWorkerTask.data;
                LogUtils.d(TAG, "cancelWork - cancelled work for " + bitmapData);
            }
        }
    }

    /**
     * Returns true if the current work has been canceled or if there was no
     * work in progress on this image view. Returns false if the work in
     * progress deals with the same data. The work is not stopped in that case.
     */
    public static boolean cancelPotentialWork(Object data, ImageView imageView) {
        final BitmapWorkerTask bitmapWorkerTask = getBitmapWorkerTask(imageView);

        if (bitmapWorkerTask != null) {
            final Object bitmapData = bitmapWorkerTask.data;
            if (bitmapData == null || !bitmapData.equals(data)) {
                bitmapWorkerTask.cancel(true);
                // if (BuildConfig.DEBUG) {
                // LogUtils.d(TAG, "cancelPotentialWork - cancelled work for "
                // + data);
                // }
            } else {
                // The same work is already in progress.
                return false;
            }
        }
        return true;
    }

    /**
     * @param imageView
     *            Any imageView
     * @return Retrieve the currently active work task (if any) associated with
     *         this imageView. null if there is no such task.
     */
    private 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 abstract String getCacheKeyFromObject(Object object);

    /**
     * The actual AsyncTask that will asynchronously process the image.
     */
    private class BitmapWorkerTask extends AsyncTask<Object, Void, BitmapDrawable> {
        private Object data;
        private int mWidth;
        private int mHeight;
        private int mGender;
        private boolean mHasCover;
        private boolean mIsCircle;
        private final WeakReference<ImageView> imageViewReference;
        private ImageListener mImageListener;

        public BitmapWorkerTask(ImageView imageView, int width, int height, int gender, boolean hasCover,
                boolean isCircle, ImageListener imageListener) {
            imageViewReference = new WeakReference<ImageView>(imageView);
            mWidth = width;
            mHeight = height;
            mGender = gender;
            mHasCover = hasCover;
            mIsCircle = isCircle;
            mImageListener = imageListener;
        }

        /**
         * Background processing.
         */
        @Override
        protected BitmapDrawable doInBackground(Object... params) {
            // if (BuildConfig.DEBUG) {
            // LogUtils.d(TAG, "doInBackground - starting work");
            // }

            data = params[0];
            final String dataString = getCacheKeyFromObject(data);
            Bitmap bitmap = null;
            BitmapDrawable drawable = null;

            // Wait here if work is paused and the task is not cancelled
            synchronized (mPauseWorkLock) {
                while (mPauseWork && !isCancelled()) {
                    try {
                        mPauseWorkLock.wait();
                    } catch (InterruptedException e) {
                    }
                }
            }

            // If the image cache is available and this task has not been
            // cancelled by another
            // thread and the ImageView that was originally bound to this task
            // is still bound back
            // to this task and our "exit early" flag is not set then try and
            // fetch the bitmap from
            // the cache
            if (mImageCache != null && !isCancelled() && getAttachedImageView() != null && !mExitTasksEarly) {
                bitmap = mImageCache.getBitmapFromDiskCache(dataString, mWidth, mHeight);
            }

            // If the bitmap was not found in the cache and this task has not
            // been cancelled by
            // another thread and the ImageView that was originally bound to
            // this task is still
            // bound back to this task and our "exit early" flag is not set,
            // then call the main
            // process method (as implemented by a subclass)
            if (bitmap == null && !isCancelled() && getAttachedImageView() != null && !mExitTasksEarly) {
                bitmap = processBitmap(params[0], mWidth, mHeight);
            }

            // If the bitmap was processed and the image cache is available,
            // then add the processed
            // bitmap to the cache for future use. Note we don't check if the
            // task was cancelled
            // here, if it was, and the thread is still running, we may as well
            // add the processed
            // bitmap to our cache as it might be used again in the future
            if (bitmap != null && mIsCircle) {
                bitmap = Utils.getBitmapInCircle(bitmap);
            }
            if (bitmap != null) {
                if (Utils.hasHoneycomb()) {
                    // Running on Honeycomb or newer, so wrap in a standard
                    // BitmapDrawable
                    drawable = new BitmapDrawable(mResources, bitmap);
                } else {
                    // Running on Gingerbread or older, so wrap in a
                    // RecyclingBitmapDrawable
                    // which will recycle automagically
                    drawable = new RecyclingBitmapDrawable(mResources, bitmap);
                }

                if (mImageCache != null) {
                    mImageCache.addBitmapToCache(dataString, drawable);
                }
            }

            // if (BuildConfig.DEBUG) {
            // LogUtils.d(TAG, "doInBackground - finished work");
            // }

            return drawable;
        }

        /**
         * Once the image is processed, associates it to the imageView
         */
        @Override
        protected void onPostExecute(BitmapDrawable value) {
            // if cancel was called on this task or the "exit early" flag is set
            // then we're done
            if (isCancelled() || mExitTasksEarly) {
                value = null;
            }
            if (mImageListener != null && value != null && value.getBitmap() != null) {
                mImageListener.onGetImageSuccess(value.getBitmap());
            }

            final ImageView imageView = getAttachedImageView();
            if (value != null && imageView != null) {
                // if (BuildConfig.DEBUG) {
                // LogUtils.d(TAG, "onPostExecute - setting bitmap");
                // }
                setImageDrawable(imageView, value, mGender, mHasCover, mIsCircle);
            }
        }

        @Override
        protected void onCancelled(BitmapDrawable value) {
            super.onCancelled(value);
            synchronized (mPauseWorkLock) {
                mPauseWorkLock.notifyAll();
            }
        }

        /**
         * Returns the ImageView associated with this task as long as the
         * ImageView's task still points to this task as well. Returns null
         * otherwise.
         */
        private ImageView getAttachedImageView() {
            final ImageView imageView = imageViewReference.get();
            final BitmapWorkerTask bitmapWorkerTask = getBitmapWorkerTask(imageView);

            if (this == bitmapWorkerTask) {
                return imageView;
            }

            return null;
        }
    }

    /**
     * A custom Drawable that will be attached to the imageView while the work
     * is in progress. Contains a reference to the actual worker task, so that
     * it can be stopped if a new binding is required, and makes sure that only
     * the last started worker process can bind its result, independently of the
     * finish order.
     */
    private 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();
        }
    }

    /**
     * Called when the processing is complete and the final drawable should be
     * set on the ImageView.
     * 
     * @param imageView
     * @param drawable
     */
    // Tamtd - Khong cho phep thay doi background
    // @SuppressWarnings("deprecation")
    // @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
    private void setImageDrawable(ImageView imageView, Drawable drawable, int gender, boolean hasCover,
            boolean isCircle) {
        imageView.setImageDrawable(drawable);

        // tungdx: Do not use below source code because it can't work with
        // CircleImageView, shouldn't use fadeInBitmap cause CircleImageView
        // can't not get Bitmap from TransitionDrawable that set to ImageView.

        /**
         * 
         if (mFadeInBitmap) { // Transition drawable with a transparent
         * drawable and the final // drawable Drawable background =
         * imageView.getDrawable(); if(background == null){ background = new
         * ColorDrawable(android.R.color.transparent); } final
         * TransitionDrawable td = new TransitionDrawable( new Drawable[]
         * {background, drawable}); td.setCrossFadeEnabled(true); // Bitmap
         * bitmap = getBitmapCover(hasCover, gender,isCircle); // if
         * (Utility.hasJELLY()) { // imageView.setBackground(new
         * BitmapDrawable(mResources, bitmap)); // } else { //
         * imageView.setBackgroundDrawable(new BitmapDrawable(mResources, //
         * bitmap)); // } imageView.setImageDrawable(td);
         * td.startTransition(FADE_IN_TIME); //
         * imageView.setBackgroundResource(android.R.color.transparent); } else
         * { imageView.setImageDrawable(drawable); }
         */
    }

    /**
     * Pause any ongoing background work. This can be used as a temporary
     * measure to improve performance. For example background work could be
     * paused when a ListView or GridView is being scrolled using a
     * {@link android.widget.AbsListView.OnScrollListener} to keep scrolling
     * smooth.
     * <p>
     * If work is paused, be sure setPauseWork(false) is called again before
     * your fragment or activity is destroyed (for example during
     * {@link android.app.Activity#onPause()}), or there is a risk the
     * background thread will never finish.
     */
    public void setPauseWork(boolean pauseWork) {
        synchronized (mPauseWorkLock) {
            mPauseWork = pauseWork;
            if (!mPauseWork) {
                mPauseWorkLock.notifyAll();
            }
        }
    }

    protected class CacheAsyncTask extends AsyncTask<Object, Void, Void> {

        @Override
        protected Void doInBackground(Object... params) {
            switch ((Integer) params[0]) {
            case MESSAGE_CLEAR:
                clearCacheInternal();
                break;
            case MESSAGE_INIT_DISK_CACHE:
                initDiskCacheInternal();
                break;
            case MESSAGE_FLUSH:
                flushCacheInternal();
                break;
            case MESSAGE_CLOSE:
                closeCacheInternal();
                break;
            }
            return null;
        }
    }

    protected void initDiskCacheInternal() {
        if (mImageCache != null) {
            mImageCache.initDiskCache();
        }
    }

    protected void clearCacheInternal() {
        if (mImageCache != null) {
            mImageCache.clearCache();
        }
    }

    protected void flushCacheInternal() {
        if (mImageCache != null) {
            mImageCache.flush();
        }
    }

    protected void closeCacheInternal() {
        if (mImageCache != null) {
            mImageCache.close();
            mImageCache = null;
        }
    }

    public void clearCache() {
        new CacheAsyncTask().execute(MESSAGE_CLEAR);
    }

    public void flushCache() {
        new CacheAsyncTask().execute(MESSAGE_FLUSH);
    }

    public void closeCache() {
        new CacheAsyncTask().execute(MESSAGE_CLOSE);
    }

    protected Bitmap fixOrientation(Bitmap bitmap, String path, int reqWidth, int reqHeight) {
        int angle = Utility.getAngle(path);
        return Utility.rotateImage(bitmap, angle);
    }

}