java.lang.RuntimeException: 在 Android 中执行 doInBackground() 时出错

Question

我正在开发一个应用程序，用户可以在其中销售或购买二手物品。在我的第一个 activity 中，我有网格视图，我在其中显示缩略图，当用户单击图像时，它会将他带到细节 activity。我使用后退按钮返回主 activity 页面。它工作正常，但如果我单击 8-9 个图像并出现内存不足 (OOM)，它就会崩溃。

CustomVolleyRequest Class

public class CustomVolleyRequest {

    private static CustomVolleyRequest customVolleyRequest;
    private static Context context;
    private RequestQueue requestQueue;
    private ImageLoader imageLoader;


    private CustomVolleyRequest(Context context) {
        this.context = context;
        this.requestQueue = getRequestQueue();

        imageLoader = new ImageLoader(requestQueue,
                new ImageLoader.ImageCache() {
                    private final LruCache<String, Bitmap>
                            cache = new LruCache<String, Bitmap>(20);

                    @Override
                    public Bitmap getBitmap(String url) {
                        return cache.get(url);
                    }

                    @Override
                    public void putBitmap(String url, Bitmap bitmap) {
                        cache.put(url, bitmap);
                    }
                });
    }

    public static synchronized CustomVolleyRequest getInstance(Context context) {
        if (customVolleyRequest == null) {
            customVolleyRequest = new CustomVolleyRequest(context);
        }
        return customVolleyRequest;
    }

    public RequestQueue getRequestQueue() {
        if (requestQueue == null) {
            Cache cache = new DiskBasedCache(context.getCacheDir(), 10 * 1024 * 1024);
            Network network = new BasicNetwork(new HurlStack());
            requestQueue = new RequestQueue(cache, network);
            requestQueue.start();
        }
        return requestQueue;
    }

    public ImageLoader getImageLoader() {
        return imageLoader;
    }

}

内存监控，每次点击都会增加，当我回到主界面时它会释放内存 activity!

堆栈跟踪：

E/AndroidRuntime: FATAL EXCEPTION: AsyncTask  E/AndroidRuntime: 
Process: PID: 5700 
java.lang.RuntimeException: An error occured while executing
doInBackground()  E/AndroidRuntime:     at
android.os.AsyncTask.done(AsyncTask.java:300)  E/AndroidRuntime:     at
java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
E/AndroidRuntime:     at
java.util.concurrent.FutureTask.setException(FutureTask.java:222)
E/AndroidRuntime:     at
java.util.concurrent.FutureTask.run(FutureTask.java:242)
E/AndroidRuntime:     at
android.os.AsyncTask$SerialExecutor.run(AsyncTask.java:231)
E/AndroidRuntime:     at
 java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
E/AndroidRuntime:     at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
E/AndroidRuntime:     at java.lang.Thread.run(Thread.java:841) 
E/AndroidRuntime:  Caused by: java.lang.OutOfMemoryError
E/AndroidRuntime:     at
android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
E/AndroidRuntime:     at
android.graphics.BitmapFactory.decodeStreamInternal(BitmapFactory.java:613)
E/AndroidRuntime:     at
android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:589)
E/AndroidRuntime:     at
android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:627)
E/AndroidRuntime:     at
 com.example.xxx.xxx.DownloadImageTask.doInBackground(DownloadImageTask.java:26)
E/AndroidRuntime:     at
 com.example.xxx.xxx.DownloadImageTask.doInBackground(DownloadImageTask.java:14)
E/AndroidRuntime:     at
android.os.AsyncTask.call(AsyncTask.java:288)
E/AndroidRuntime:     at
java.util.concurrent.FutureTask.run(FutureTask.java:237)
E/AndroidRuntime:     at
android.os.AsyncTask$SerialExecutor.run(AsyncTask.java:231)
E/AndroidRuntime:     at
 java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112) 
E/AndroidRuntime:     at
 java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587) 
E/AndroidRuntime:     at java.lang.Thread.run(Thread.java:841)

Answer 1

根据日志，查看这一行：

E/AndroidRuntime:  Caused by: java.lang.OutOfMemoryError

它清楚地表明应用程序崩溃只是因为 OutOfMemoryError 异常。一个可能的原因可能是您正在处理大尺寸位图而没有缩小它们的比例。在将位图设置为图像视图之前，您需要调整大小和缩小位图。

有关如何有效管理位图的详细信息，请参阅官方docs

java.lang.RuntimeException: 在 Android 中执行 doInBackground() 时出错

java.lang.RuntimeException: An error occured while executing doInBackground() in Android

android

android-volley