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      1 /*
      2  * Copyright (C) 2012 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.contacts.util;
     18 
     19 import android.content.res.Resources;
     20 import android.content.res.Resources.NotFoundException;
     21 import android.graphics.Bitmap;
     22 import android.graphics.BitmapFactory;
     23 import android.graphics.drawable.BitmapDrawable;
     24 import android.graphics.drawable.Drawable;
     25 import android.graphics.drawable.TransitionDrawable;
     26 import android.util.Log;
     27 import android.widget.ImageView;
     28 
     29 import com.android.contacts.common.ContactPhotoManager;
     30 import com.android.contacts.common.model.Contact;
     31 
     32 import java.util.Arrays;
     33 
     34 /**
     35  * Initialized with a target ImageView. When provided with a compressed image
     36  * (i.e. a byte[]), it appropriately updates the ImageView's Drawable.
     37  */
     38 public class ImageViewDrawableSetter {
     39     private ImageView mTarget;
     40     private byte[] mCompressed;
     41     private Drawable mPreviousDrawable;
     42     private int mDurationInMillis = 0;
     43     private static final String TAG = "ImageViewDrawableSetter";
     44 
     45     public ImageViewDrawableSetter() {
     46     }
     47 
     48     public ImageViewDrawableSetter(ImageView target) {
     49         mTarget = target;
     50     }
     51 
     52     public void setupContactPhoto(Contact contactData, ImageView photoView) {
     53         setTarget(photoView);
     54         setCompressedImage(contactData.getPhotoBinaryData());
     55     }
     56 
     57     public void setTransitionDuration(int durationInMillis) {
     58         mDurationInMillis = durationInMillis;
     59     }
     60 
     61     public ImageView getTarget() {
     62         return mTarget;
     63     }
     64 
     65     /**
     66      * Re-initialize to use new target. As a result, the next time a new image
     67      * is set, it will immediately be applied to the target (there will be no
     68      * fade transition).
     69      */
     70     protected void setTarget(ImageView target) {
     71         if (mTarget != target) {
     72             mTarget = target;
     73             mCompressed = null;
     74             mPreviousDrawable = null;
     75         }
     76     }
     77 
     78     protected byte[] getCompressedImage() {
     79         return mCompressed;
     80     }
     81 
     82     protected Bitmap setCompressedImage(byte[] compressed) {
     83         if (mPreviousDrawable == null) {
     84             // If we don't already have a drawable, skip the exit-early test
     85             // below; otherwise we might not end up setting the default image.
     86         } else if (mPreviousDrawable != null && Arrays.equals(mCompressed, compressed)) {
     87             // TODO: the worst case is when the arrays are equal but not
     88             // identical. This takes about 1ms (more with high-res photos). A
     89             // possible optimization is to sparsely sample chunks of the arrays
     90             // to compare.
     91             return previousBitmap();
     92         }
     93 
     94         final Drawable newDrawable = (compressed == null)
     95                 ? defaultDrawable()
     96                 : decodedBitmapDrawable(compressed);
     97 
     98         // Remember this for next time, so that we can check if it changed.
     99         mCompressed = compressed;
    100 
    101         // If we don't have a new Drawable, something went wrong... bail out.
    102         if (newDrawable == null) return previousBitmap();
    103 
    104         if (mPreviousDrawable == null || mDurationInMillis == 0) {
    105             // Set the new one immediately.
    106             mTarget.setImageDrawable(newDrawable);
    107         } else {
    108             // Set up a transition from the previous Drawable to the new one.
    109             final Drawable[] beforeAndAfter = new Drawable[2];
    110             beforeAndAfter[0] = mPreviousDrawable;
    111             beforeAndAfter[1] = newDrawable;
    112             final TransitionDrawable transition = new TransitionDrawable(beforeAndAfter);
    113             mTarget.setImageDrawable(transition);
    114             transition.startTransition(mDurationInMillis);
    115         }
    116 
    117         // Remember this for next time, so that we can transition from it to the
    118         // new one.
    119         mPreviousDrawable = newDrawable;
    120 
    121         return previousBitmap();
    122     }
    123 
    124     private Bitmap previousBitmap() {
    125         return (mPreviousDrawable == null)
    126                 ? null
    127                 : ((BitmapDrawable) mPreviousDrawable).getBitmap();
    128     }
    129 
    130     /**
    131      * Obtain the default drawable for a contact when no photo is available.
    132      */
    133     private Drawable defaultDrawable() {
    134         Resources resources = mTarget.getResources();
    135         final int resId = ContactPhotoManager.getDefaultAvatarResId(true, false);
    136         try {
    137             return resources.getDrawable(resId);
    138         } catch (NotFoundException e) {
    139             Log.wtf(TAG, "Cannot load default avatar resource.");
    140             return null;
    141         }
    142     }
    143 
    144     private BitmapDrawable decodedBitmapDrawable(byte[] compressed) {
    145         Resources rsrc = mTarget.getResources();
    146         Bitmap bitmap = BitmapFactory.decodeByteArray(compressed, 0, compressed.length);
    147         return new BitmapDrawable(rsrc, bitmap);
    148     }
    149 
    150 }
    151