| /* |
| * Copyright (C) 2013 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.example.android.displayingbitmaps.util; |
| |
| import android.content.res.Resources; |
| import android.graphics.Bitmap; |
| import android.graphics.drawable.BitmapDrawable; |
| |
| import com.example.android.common.logger.Log; |
| import com.example.android.displayingbitmaps.BuildConfig; |
| |
| /** |
| * A BitmapDrawable that keeps track of whether it is being displayed or cached. |
| * When the drawable is no longer being displayed or cached, |
| * {@link android.graphics.Bitmap#recycle() recycle()} will be called on this drawable's bitmap. |
| */ |
| public class RecyclingBitmapDrawable extends BitmapDrawable { |
| |
| static final String TAG = "CountingBitmapDrawable"; |
| |
| private int mCacheRefCount = 0; |
| private int mDisplayRefCount = 0; |
| |
| private boolean mHasBeenDisplayed; |
| |
| public RecyclingBitmapDrawable(Resources res, Bitmap bitmap) { |
| super(res, bitmap); |
| } |
| |
| /** |
| * Notify the drawable that the displayed state has changed. Internally a |
| * count is kept so that the drawable knows when it is no longer being |
| * displayed. |
| * |
| * @param isDisplayed - Whether the drawable is being displayed or not |
| */ |
| public void setIsDisplayed(boolean isDisplayed) { |
| //BEGIN_INCLUDE(set_is_displayed) |
| synchronized (this) { |
| if (isDisplayed) { |
| mDisplayRefCount++; |
| mHasBeenDisplayed = true; |
| } else { |
| mDisplayRefCount--; |
| } |
| } |
| |
| // Check to see if recycle() can be called |
| checkState(); |
| //END_INCLUDE(set_is_displayed) |
| } |
| |
| /** |
| * Notify the drawable that the cache state has changed. Internally a count |
| * is kept so that the drawable knows when it is no longer being cached. |
| * |
| * @param isCached - Whether the drawable is being cached or not |
| */ |
| public void setIsCached(boolean isCached) { |
| //BEGIN_INCLUDE(set_is_cached) |
| synchronized (this) { |
| if (isCached) { |
| mCacheRefCount++; |
| } else { |
| mCacheRefCount--; |
| } |
| } |
| |
| // Check to see if recycle() can be called |
| checkState(); |
| //END_INCLUDE(set_is_cached) |
| } |
| |
| private synchronized void checkState() { |
| //BEGIN_INCLUDE(check_state) |
| // If the drawable cache and display ref counts = 0, and this drawable |
| // has been displayed, then recycle |
| if (mCacheRefCount <= 0 && mDisplayRefCount <= 0 && mHasBeenDisplayed |
| && hasValidBitmap()) { |
| if (BuildConfig.DEBUG) { |
| Log.d(TAG, "No longer being used or cached so recycling. " |
| + toString()); |
| } |
| |
| getBitmap().recycle(); |
| } |
| //END_INCLUDE(check_state) |
| } |
| |
| private synchronized boolean hasValidBitmap() { |
| Bitmap bitmap = getBitmap(); |
| return bitmap != null && !bitmap.isRecycled(); |
| } |
| |
| } |