Question

这里我正逐一从服务器下载图片。获取dalvikvm-heap的错误：在运行应用程序时在31961104字节分配内存不足并在中间崩溃。有时候某些时间图像下载没有。但是我想从下载中添加Listview中的图像..

这是我的下载代码

   private Bitmap downloadBitmap(String url) {

            final DefaultHttpClient client = new DefaultHttpClient();

            final HttpGet getRequest = new HttpGet(url);
            try {
                HttpResponse response = client.execute(getRequest);

                //check 200 OK for success
                final int statusCode = response.getStatusLine().getStatusCode();

                if (statusCode != HttpStatus.SC_OK) {
                    Log.w("ImageDownloader", "Error " + statusCode +
                            " while retrieving bitmap from " + url);
                    return null;
                }
                final HttpEntity entity = response.getEntity();
                if (entity != null) {
                    InputStream inputStream = null;
                    try {
                        // getting contents from the stream
                        inputStream = entity.getContent();

                        // decoding stream data back into image Bitmap that android understands
                        BitmapFactory.Options options = new BitmapFactory.Options();
                        options.inSampleSize = 1;
                        final Bitmap bitmap = BitmapFactory.decodeStream(inputStream, null, options);
                       // final Bitmap bitmap = BitmapFactory.decodeStream(inputStream);

                        File file = new File(newFolder, imageName);

                        if (file.exists()) file.delete();
                        try
                        {
                            FileOutputStream out = new FileOutputStream(file);
                            bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);
                            out.flush();
                            out.close();
                            int imagenObtenidaW = bitmap.getWidth();
                            int imagenObtenidaH = bitmap.getHeight();
                            Log.e("imagenObtenidaW " ," = +" + imagenObtenidaW + " imagenObtenidaH = " + imagenObtenidaH);

                        } catch (Exception e) {

                        }

                        return bitmap;
                    } finally {
                        if (inputStream != null) {
                            inputStream.close();
                        }
                        entity.consumeContent();
                    }
                }
            } catch (Exception e) {
                // You Could provide a more explicit error message for IOException
                getRequest.abort();
                Log.e("ImageDownloader", "Something went wrong while" +
                        " retrieving bitmap from " + url + e.toString());
            }
            return null;
        }

    here is my code form download in the same Activity.

    if (imageName.endsWith(png_Pattern) || imageName.endsWith(jpg_pattern) || imageName.endsWith(bmp_pattern) || imageName.endsWith(gif_pattern) || imageName.endsWith(jpeg_pattern))
                        {

                            str_DownLoadUrl = namespace + "/DownloadFile/FileName/" + imageName;
                            Log.e("@@@@@", "str_DownLoadUrl  = " + str_DownLoadUrl);
                            //download_PngFile(str_DownLoadUrl);
                            downloadBitmap(str_DownLoadUrl);
                            strDownLoadStatus = "1";
                            dbhelper.update_DownLoadStatus(imageName, strDownLoadStatus);
                        }
                    }

这是我的logcat

1.414  10598-10601/com.example.tazeen.classnkk D/dalvikvm﹕ GC_CONCURRENT freed 1738K, 57% free 15379K/35335K, paused 5ms+7ms
10-13 14:52:11.963  10598-10826/com.example.tazeen.classnkk D/dalvikvm﹕ GC_FOR_ALLOC freed 64K, 57% free 15377K/35335K, paused 95ms
10-13 14:52:11.963  10598-10826/com.example.tazeen.classnkk I/dalvikvm-heap﹕ Forcing collection of SoftReferences for 31961104-byte allocation
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk D/dalvikvm﹕ GC_BEFORE_OOM freed 9K, 57% free 15368K/35335K, paused 68ms
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk E/dalvikvm-heap﹕ Out of memory on a 31961104-byte allocation.
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ "AsyncTask #2" prio=5 tid=13 RUNNABLE
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ | group="main" sCount=0 dsCount=0 obj=0x42ad4188 self=0x1edbd8
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ | sysTid=10826 nice=10 sched=0/0 cgrp=bg_non_interactive handle=1591808
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ | schedstat=( 12449561867 3389288161 878 ) utm=1181 stm=63 core=0
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:493)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at com.example.tazeen.classnkk.AllPosts_Page.downloadBitmap(AllPosts_Page.java:1220)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at com.example.tazeen.classnkk.AllPosts_Page.getDoenLoaddata(AllPosts_Page.java:738)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at com.example.tazeen.classnkk.AllPosts_Page$GetgetDoenLoaddata.doInBackground(AllPosts_Page.java:700)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at com.example.tazeen.classnkk.AllPosts_Page$GetgetDoenLoaddata.doInBackground(AllPosts_Page.java:696)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at android.os.AsyncTask$2.call(AsyncTask.java:264)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at java.util.concurrent.FutureTask.run(FutureTask.java:137)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ at java.lang.Thread.run(Thread.java:856)
10-13 14:52:12.034  10598-10826/com.example.tazeen.classnkk I/dalvikvm﹕ [ 10-13 14:52:12.034 10598:0x2a4a D/skia     ]
    --- decoder->decode returned false

如何解决这个问题。

Answer 1

当您下载图像时，会出现此问题，并且在下载某些图像后没有剩余的内存分配给您的应用程序。有各种图像加载库可以让您的工作更轻松：Fresco，Picasso，Glide等。

我建议您查看图片管理库（Facebook），Fresco与其他图片加载库相比非常棒且成熟。
< / LI>
Fresco拥有SimpleDraweeView作为自定义图片视图，支持Rounded Corners and Circles link并支持动画（.gif，.webp）以及普通图像（.jpg，.png））。
Fresco使用3层架构（BITMAP_MEMORY_CACHE，ENCODED_MEMORY_CACHE和DISK_CACHE）处理图像的所有缓存。它还减少了OOM（Out Of Memory）问题。当视图中的图像离开屏幕时，它会自动回收位图，从而释放内存。

您可以通过在清单中添加android:largeHeap="true"来增加分配给您的应用程序的内存。

注意：为您的应用程序增加heap并不被视为理想的解决方案。

以下是Google解压缩的摘录，

但是，请求大堆的功能仅适用于a 一小组应用程序，可以证明需要消耗更多的RAM（例如作为一个大型照片编辑应用程序）。永远不要简单地请求大堆因为你的内存耗尽，需要快速修复 - 你应该这样做只有当你确切知道所有记忆的存在时才使用它分配以及必须保留的原因。然而，即使你有信心你的应用程序可以证明大堆的合理性，你应该避免请求它尽可能的。使用额外的内存将越来越多因为垃圾而损害整体用户体验收集将花费更长时间，系统性能可能会更慢任务切换或执行其他常见操作。

这是文档https://developer.android.com/training/articles/memory.html

Android：dalvikvm-heap：内存不足

1 个答案: