java - android 2.3 出现内存泄漏错误

Question

我最近遇到了内存泄漏错误，我想做的是创建一个带有画廊的 Activity ，从服务下载图片并显示它们，第一次出现错误时，我做了一些调查，发现这要么是上下文的引用，要么是不同版本的android管理内存中图像的方式。我对代码做了一些更改，最终得到了这样的结果:

public class GalleryView extends Activity {
private LinearLayout imageView;
private String GalleryId;
private ArrayList<Drawable> images = new ArrayList<Drawable>();
private ArrayList<Drawable> thumbs = new ArrayList<Drawable>();
private ArrayList<String> urls;
private AdvertiserDAO aDao = new AdvertiserDAO();


/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.galeria);

    setGallery();

    setThumbs();

    Button back = (Button) findViewById(R.id.Back);

    back.setOnClickListener(new View.OnClickListener() {

        public void onClick(View v) {
            finish();

        }
    });

    Gallery ga = (Gallery) findViewById(R.id.Gallery01);

    ga.setAdapter(new ImageAdapter(this));

    imageView = (LinearLayout) findViewById(R.id.ImageView01);
    ga.setOnItemClickListener(new OnItemClickListener() {
        public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
                long arg3) {

            try {
                imageView.removeAllViews();

            } catch (Exception e) {
                e.getMessage();
            }
            TouchImageView touchImageView = new TouchImageView(
                    GalleryView.this);
            touchImageView.setImageDrawable(images.get(arg2));

            LayoutParams lp = new LayoutParams(LayoutParams.FILL_PARENT,
                    LayoutParams.FILL_PARENT);
            imageView.setGravity(Gravity.CENTER_HORIZONTAL
                    | Gravity.CENTER_VERTICAL);
            touchImageView.setLayoutParams(lp);
            imageView.addView(touchImageView);

        }

    });

}

private void setGallery()  {

    SharedPreferences sp = getSharedPreferences("galeriaId", 0);
    GalleryId = sp.getString("galeriaId", null);

    //retrieves urls of the pictures of the gallery
            urls = aDao.getUrls(GalleryId);

    for (int i = 0; i < urls.size(); i++) {

        Drawable d = ImageOperations(urls.get(i), "image" + i
                + ".jpg");
        images.add(d);
    }

}

private void setThumbs()  {

    SharedPreferences sp = getSharedPreferences("galeriaId", 0);
    GalleryId = sp.getString("galeriaId", null);

            //retrieves the urls of the thumbs of the gallery
    urls = aDao.getThumbs(GalleryId);

    for (int i = 0; i < urls.size(); i++) {

        Drawable d = ImageOperations( urls.get(i), "image" + i
                + ".jpg");
        thumbs.add(d);
    }
}

private Drawable ImageOperations(String url,
        String saveFilename)  {

    InputStream is = (InputStream) fetch(url);

    Drawable d = null;
    try {
        d = new ImageOperationsAsyncTask().execute(is).get();
    } catch (InterruptedException e) {
        Log.e(TAG, e.toString());
        e.printStackTrace();
    } catch (ExecutionException e) {
        Log.e(TAG, e.toString());
        e.printStackTrace();
    }

    return d;

}

public Object fetch(String address)  {

    Object content = null;
    try {
        content = new URLAsyncTAsk().execute(address).get();
    } catch (InterruptedException e) {
        Log.e(TAG, e.toString());
        e.printStackTrace();
    } catch (ExecutionException e) {
        Log.e(TAG, e.toString());
        e.printStackTrace();
    }

    return content;
}

private class ImageOperationsAsyncTask extends
        AsyncTask<InputStream, Integer, Drawable> {

    @Override
    protected Drawable doInBackground(InputStream... params) {

        InputStream is = null;

        for(InputStream i: params){

            is = i;
        }

        Drawable result = Drawable.createFromStream(is, "src");

        return result;
    }

}

private class URLAsyncTAsk extends AsyncTask<String, Integer, Object> {


    @Override
    protected Object doInBackground(String... params) {
        String address = "";
        for (String s : params) {
            address = s;
        }

        URL url;
        Object content = null;
        try {

            url = new URL(address);

            content = url.getContent();

        } catch (MalformedURLException e) {
            Log.e(TAG, e.toString());
            e.printStackTrace();
        } catch (IOException e) {
            Log.e(TAG, e.toString());
            e.printStackTrace();
        }

        return content;
    }

}

public class ImageAdapter extends BaseAdapter {

    private Context ctx;
    int imageBackground;

    public ImageAdapter(Context c) {

        ctx = c;
        TypedArray ta = obtainStyledAttributes(R.styleable.Gallery1);
        imageBackground = ta.getResourceId(
                R.styleable.Gallery1_android_galleryItemBackground, 1);

        ta.recycle();
    }

    public int getCount() {

        return images.size();
    }

    public Object getItem(int arg0) {

        return arg0;
    }

    public long getItemId(int arg0) {

        return arg0;
    }

    public View getView(int arg0, View arg1, ViewGroup arg2) {
        ImageView iv = new ImageView(ctx);
        iv.setImageDrawable(thumbs.get(arg0));

        iv.setScaleType(ImageView.ScaleType.FIT_XY);
        iv.setLayoutParams(new Gallery.LayoutParams(150, 120));
        iv.setBackgroundResource(imageBackground);
        return iv;
    }
}}

此代码适用于我的 android 4.1 手机和 android 2.2 模拟器，但在 android 2.3 模拟器和手机上，它仍然在日志猫中显示内存泄漏错误。

知道为什么它只在 android 2.3 中不起作用吗？？？

编辑:以下是 LogCat 发布的日志:

06-17 14:41:45.050: W/System.err(305): java.util.concurrent.ExecutionException: java.lang.OutOfMemoryError: bitmap size exceeds VM budget
06-17 14:41:45.060: W/System.err(305):  at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:224)
06-17 14:41:45.060: W/System.err(305):  at java.util.concurrent.FutureTask.get(FutureTask.java:83)
06-17 14:41:45.060: W/System.err(305):  at android.os.AsyncTask.get(AsyncTask.java:340)
06-17 14:41:45.060: W/System.err(305):  at directorio.actividades.GalleryView.ImageOperations(GalleryView.java:140)
06-17 14:41:45.060: W/System.err(305):  at directorio.actividades.GalleryView.setGallery(GalleryView.java:107)
06-17 14:41:45.060: W/System.err(305):  at directorio.actividades.GalleryView.onCreate(GalleryView.java:50)
06-17 14:41:45.060: W/System.err(305):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
06-17 14:41:45.060: W/System.err(305):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
06-17 14:41:45.060: W/System.err(305):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
06-17 14:41:45.060: W/System.err(305):  at android.app.ActivityThread.access$1500(ActivityThread.java:117)
06-17 14:41:45.060: W/System.err(305):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
06-17 14:41:45.060: W/System.err(305):  at android.os.Handler.dispatchMessage(Handler.java:99)
06-17 14:41:45.060: W/System.err(305):  at android.os.Looper.loop(Looper.java:130)
06-17 14:41:45.060: W/System.err(305):  at android.app.ActivityThread.main(ActivityThread.java:3683)
06-17 14:41:45.060: W/System.err(305):  at java.lang.reflect.Method.invokeNative(Native Method)
06-17 14:41:45.060: W/System.err(305):  at java.lang.reflect.Method.invoke(Method.java:507)
06-17 14:41:45.060: W/System.err(305):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
06-17 14:41:45.060: W/System.err(305):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
06-17 14:41:45.060: W/System.err(305):  at dalvik.system.NativeStart.main(Native Method)
06-17 14:41:45.060: W/System.err(305): Caused by: java.lang.OutOfMemoryError: bitmap size exceeds VM budget
06-17 14:41:45.060: W/System.err(305):  at android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
06-17 14:41:45.060: W/System.err(305):  at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:470)
06-17 14:41:45.060: W/System.err(305):  at android.graphics.BitmapFactory.decodeResourceStream(BitmapFactory.java:336)
06-17 14:41:45.060: W/System.err(305):  at android.graphics.drawable.Drawable.createFromResourceStream(Drawable.java:697)
06-17 14:41:45.060: W/System.err(305):  at android.graphics.drawable.Drawable.createFromStream(Drawable.java:657)
06-17 14:41:45.060: W/System.err(305):  at directorio.actividades.GalleryView$ImageOperationsAsyncTask.doInBackground(GalleryView.java:195)

Answer 1

这里的问题本身并不是内存泄漏，真正的问题是异常所指向的问题:

OutOfMemoryError: bitmap size exceeds VM budget

检查引发异常的行，您会发现它与正在加载的图像有关。该图像太大，处理它所消耗的内存不足以完成任务。

您可以在 this other answer 上找到很好的引用资料。一个好的方法是使用 options BitmapFactory的类和decode仅当您找到可以防止 OutOfMemory 的正确采样时才显示图像问题发生。