canvas：试图在Android中使用回收的位图android.graphics.Bitmap
我正在裁剪图像类，但遇到一个回收的位图问题：
03-02 23:14:10.514: E/AndroidRuntime(16736): FATAL EXCEPTION: Thread-1470 03-02 23:14:10.514: E/AndroidRuntime(16736): java.lang.RuntimeException: Canvas: trying to use a recycled bitmap android.graphics.Bitmap@428e5450 03-02 23:14:10.514: E/AndroidRuntime(16736): at android.graphics.Canvas.throwIfRecycled(Canvas.java:1026) 03-02 23:14:10.514: E/AndroidRuntime(16736): at android.graphics.Canvas.drawBitmap(Canvas.java:1096) 03-02 23:14:10.514: E/AndroidRuntime(16736): at android.graphics.Bitmap.createBitmap(Bitmap.java:604) 03-02 23:14:10.514: E/AndroidRuntime(16736): at eu.janmuller.android.simplecropimage.CropImage$1.prepareBitmap(CropImage.java:630) 03-02 23:14:10.514: E/AndroidRuntime(16736): at eu.janmuller.android.simplecropimage.CropImage$1.run(CropImage.java:636) 03-02 23:14:10.514: E/AndroidRuntime(16736): at eu.janmuller.android.simplecropimage.CropImage$6.run(CropImage.java:343) 03-02 23:14:10.514: E/AndroidRuntime(16736): at eu.janmuller.android.simplecropimage.Util$BackgroundJob.run(Util.java:175) 03-02 23:14:10.514: E/AndroidRuntime(16736): at java.lang.Thread.run(Thread.java:856) 发生错误的行是mScale = 256.0F / mBitmap.getWidth(); （630行），请search这个更多的信息。
注意，在添加checkRotation（ ）函数之前，代码没有这个错误。 该函数返回一个位图，该位图引起了exception。 这是提示
此外，在我已经复制了原始位图的function，并回收旧的位图，所以它不应该是问题的根源，build议您不要一个接一个地看代码，而是search关键字。 感谢您的帮助。
/** * The activity can crop specific region of interest from an image. */ public class CropImage extends MonitoredActivity { final int IMAGE_MAX_SIZE = 1024; private static final String TAG = "CropImage"; public static final String IMAGE_PATH = "image-path"; public static final String SCALE = "scale"; public static final String ORIENTATION_IN_DEGREES = "orientation_in_degrees"; public static final String ASPECT_X = "aspectX"; public static final String ASPECT_Y = "aspectY"; public static final String OUTPUT_X = "outputX"; public static final String OUTPUT_Y = "outputY"; public static final String SCALE_UP_IF_NEEDED = "scaleUpIfNeeded"; public static final String CIRCLE_CROP = "circleCrop"; public static final String RETURN_DATA = "return-data"; public static final String RETURN_DATA_AS_BITMAP = "data"; public static final String ACTION_INLINE_DATA = "inline-data"; // These are various options can be specified in the intent. private Bitmap.CompressFormat mOutputFormat = Bitmap.CompressFormat.JPEG; private Uri mSaveUri = null; private boolean mDoFaceDetection = true; private boolean mCircleCrop = false; private final Handler mHandler = new Handler(); private int mAspectX; private int mAspectY; private int mOutputX; private int mOutputY; private boolean mScale; private CropImageView mImageView; private ContentResolver mContentResolver; private Bitmap mBitmap; private String mImagePath; boolean mWaitingToPick; // Whether we are wait the user to pick a face. boolean mSaving; // Whether the "save" button is already clicked. HighlightView mCrop; // These options specifiy the output image size and whether we should // scale the output to fit it (or just crop it). private boolean mScaleUp = true; private final BitmapManager.ThreadSet mDecodingThreads = new BitmapManager.ThreadSet(); @Override public void onCreate(Bundle icicle) { super.onCreate(icicle); mContentResolver = getContentResolver(); requestWindowFeature(Window.FEATURE_NO_TITLE); setContentView(R.layout.cropimage); mImageView = (CropImageView) findViewById(R.id.image); showStorageToast(this); Intent intent = getIntent(); Bundle extras = intent.getExtras(); if (extras != null) { if (extras.getString(CIRCLE_CROP) != null) { if (Build.VERSION.SDK_INT > Build.VERSION_CODES.HONEYCOMB) { mImageView.setLayerType(View.LAYER_TYPE_SOFTWARE, null); } mCircleCrop = true; mAspectX = 1; mAspectY = 1; } mImagePath = extras.getString(IMAGE_PATH); mBitmap = checkRotation(mImagePath); Log.d("test1",""+mBitmap.isRecycled()); if (extras.containsKey(ASPECT_X) && extras.get(ASPECT_X) instanceof Integer) { mAspectX = extras.getInt(ASPECT_X); } else { throw new IllegalArgumentException("aspect_x must be integer"); } if (extras.containsKey(ASPECT_Y) && extras.get(ASPECT_Y) instanceof Integer) { mAspectY = extras.getInt(ASPECT_Y); } else { throw new IllegalArgumentException("aspect_y must be integer"); } mOutputX = extras.getInt(OUTPUT_X); mOutputY = extras.getInt(OUTPUT_Y); mScale = extras.getBoolean(SCALE, true); mScaleUp = extras.getBoolean(SCALE_UP_IF_NEEDED, true); } if (mBitmap == null) { Log.d(TAG, "finish!!!"); finish(); return; } // Make UI fullscreen. getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN); findViewById(R.id.discard).setOnClickListener( new View.OnClickListener() { public void onClick(View v) { setResult(RESULT_CANCELED); finish(); } }); findViewById(R.id.save).setOnClickListener( new View.OnClickListener() { public void onClick(View v) { try { onSaveClicked(); } catch (Exception e) { finish(); } } }); findViewById(R.id.rotateLeft).setOnClickListener( new View.OnClickListener() { public void onClick(View v) { mBitmap = Util.rotateImage(mBitmap, -90); RotateBitmap rotateBitmap = new RotateBitmap(mBitmap); mImageView.setImageRotateBitmapResetBase(rotateBitmap, true); mRunFaceDetection.run(); } }); findViewById(R.id.rotateRight).setOnClickListener( new View.OnClickListener() { public void onClick(View v) { mBitmap = Util.rotateImage(mBitmap, 90); RotateBitmap rotateBitmap = new RotateBitmap(mBitmap); mImageView.setImageRotateBitmapResetBase(rotateBitmap, true); mRunFaceDetection.run(); } }); Log.d("test1","a "+mBitmap.isRecycled()); startFaceDetection(); } private Bitmap checkRotation(String url){ mSaveUri = getImageUri(url); ExifInterface exif; try { exif = new ExifInterface(url); int rotation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_UNDEFINED); Matrix matrix = new Matrix(); switch (rotation) { case ExifInterface.ORIENTATION_FLIP_HORIZONTAL: matrix.setScale(-1, 1); break; case ExifInterface.ORIENTATION_ROTATE_180: matrix.setRotate(180); break; case ExifInterface.ORIENTATION_FLIP_VERTICAL: matrix.setRotate(180); matrix.postScale(-1, 1); break; case ExifInterface.ORIENTATION_TRANSPOSE: matrix.setRotate(90); matrix.postScale(-1, 1); break; case ExifInterface.ORIENTATION_ROTATE_90: matrix.setRotate(90); break; case ExifInterface.ORIENTATION_TRANSVERSE: matrix.setRotate(-90); matrix.postScale(-1, 1); break; case ExifInterface.ORIENTATION_ROTATE_270: matrix.setRotate(-90); break; case ExifInterface.ORIENTATION_NORMAL: default: break; } Bitmap beforeRotate = getBitmap(url); int height = beforeRotate.getHeight(); int width = beforeRotate.getWidth(); Bitmap afterRotate = Bitmap.createBitmap(beforeRotate, 0, 0, width, height, matrix, true); beforeRotate.recycle(); return afterRotate; } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return mBitmap; } private Uri getImageUri(String path) { return Uri.fromFile(new File(path)); } private Bitmap getBitmap(String path) { Uri uri = getImageUri(path); InputStream in = null; try { in = mContentResolver.openInputStream(uri); //Decode image size BitmapFactory.Options o = new BitmapFactory.Options(); o.inJustDecodeBounds = true; BitmapFactory.decodeStream(in, null, o); in.close(); int scale = 1; if (o.outHeight > IMAGE_MAX_SIZE || o.outWidth > IMAGE_MAX_SIZE) { scale = (int) Math.pow(2, (int) Math.round(Math.log(IMAGE_MAX_SIZE / (double) Math.max(o.outHeight, o.outWidth)) / Math.log(0.5))); } BitmapFactory.Options o2 = new BitmapFactory.Options(); o2.inSampleSize = scale; in = mContentResolver.openInputStream(uri); Bitmap b = BitmapFactory.decodeStream(in, null, o2); in.close(); return b; } catch (FileNotFoundException e) { Log.e(TAG, "file " + path + " not found"); } catch (IOException e) { Log.e(TAG, "file " + path + " not found"); } return null; } private void startFaceDetection() { if (isFinishing()) { return; } mImageView.setImageBitmapResetBase(mBitmap, true); Util.startBackgroundJob(this, null, "Please wait\u2026", new Runnable() { public void run() { final CountDownLatch latch = new CountDownLatch(1); final Bitmap b = mBitmap; mHandler.post(new Runnable() { public void run() { if (b != mBitmap && b != null) { Log.d("test1","test"); mImageView.setImageBitmapResetBase(b, true); mBitmap.recycle(); mBitmap = b; } if (mImageView.getScale() == 1F) { mImageView.center(true, true); } latch.countDown(); } }); try { latch.await(); } catch (InterruptedException e) { throw new RuntimeException(e); } mRunFaceDetection.run(); } }, mHandler); } private void onSaveClicked() throws Exception { // TODO this code needs to change to use the decode/crop/encode single // step api so that we don't require that the whole (possibly large) // bitmap doesn't have to be read into memory if (mSaving) return; if (mCrop == null) { return; } mSaving = true; Rect r = mCrop.getCropRect(); int width = r.width(); int height = r.height(); // If we are circle cropping, we want alpha channel, which is the // third param here. Bitmap croppedImage; try { croppedImage = Bitmap.createBitmap(width, height, mCircleCrop ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565); } catch (Exception e) { throw e; } if (croppedImage == null) { return; } { Canvas canvas = new Canvas(croppedImage); Rect dstRect = new Rect(0, 0, width, height); canvas.drawBitmap(mBitmap, r, dstRect, null); } if (mCircleCrop) { // OK, so what's all this about? // Bitmaps are inherently rectangular but we want to return // something that's basically a circle. So we fill in the // area around the circle with alpha. Note the all important // PortDuff.Mode.CLEAR. Canvas c = new Canvas(croppedImage); Path p = new Path(); p.addCircle(width / 2F, height / 2F, width / 2F, Path.Direction.CW); c.clipPath(p, Region.Op.DIFFERENCE); c.drawColor(0x00000000, PorterDuff.Mode.CLEAR); } /* If the output is required to a specific size then scale or fill */ if (mOutputX != 0 && mOutputY != 0) { if (mScale) { /* Scale the image to the required dimensions */ Bitmap old = croppedImage; croppedImage = Util.transform(new Matrix(), croppedImage, mOutputX, mOutputY, mScaleUp); if (old != croppedImage) { old.recycle(); } } else { /* Don't scale the image crop it to the size requested. * Create an new image with the cropped image in the center and * the extra space filled. */ // Don't scale the image but instead fill it so it's the // required dimension Bitmap b = Bitmap.createBitmap(mOutputX, mOutputY, Bitmap.Config.RGB_565); Canvas canvas = new Canvas(b); Rect srcRect = mCrop.getCropRect(); Rect dstRect = new Rect(0, 0, mOutputX, mOutputY); int dx = (srcRect.width() - dstRect.width()) / 2; int dy = (srcRect.height() - dstRect.height()) / 2; /* If the srcRect is too big, use the center part of it. */ srcRect.inset(Math.max(0, dx), Math.max(0, dy)); /* If the dstRect is too big, use the center part of it. */ dstRect.inset(Math.max(0, -dx), Math.max(0, -dy)); /* Draw the cropped bitmap in the center */ canvas.drawBitmap(mBitmap, srcRect, dstRect, null); /* Set the cropped bitmap as the new bitmap */ croppedImage.recycle(); croppedImage = b; } } // Return the cropped image directly or save it to the specified URI. Bundle myExtras = getIntent().getExtras(); if (myExtras != null && (myExtras.getParcelable("data") != null || myExtras.getBoolean(RETURN_DATA))) { Bundle extras = new Bundle(); extras.putParcelable(RETURN_DATA_AS_BITMAP, croppedImage); setResult(RESULT_OK, (new Intent()).setAction(ACTION_INLINE_DATA).putExtras(extras)); finish(); } else { final Bitmap b = croppedImage; Util.startBackgroundJob(this, null, getString(R.string.saving_image), new Runnable() { public void run() { saveOutput(b); } }, mHandler); } } private void saveOutput(Bitmap croppedImage) { if (mSaveUri != null) { OutputStream outputStream = null; try { outputStream = mContentResolver.openOutputStream(mSaveUri); if (outputStream != null) { croppedImage.compress(mOutputFormat, 90, outputStream); } } catch (IOException ex) { Log.e(TAG, "Cannot open file: " + mSaveUri, ex); setResult(RESULT_CANCELED); finish(); return; } finally { Util.closeSilently(outputStream); } Bundle extras = new Bundle(); Intent intent = new Intent(mSaveUri.toString()); intent.putExtras(extras); intent.putExtra(IMAGE_PATH, mImagePath); intent.putExtra(ORIENTATION_IN_DEGREES, Util.getOrientationInDegree(this)); setResult(RESULT_OK, intent); } else { Log.e(TAG, "not defined image url"); } croppedImage.recycle(); finish(); } @Override protected void onPause() { super.onPause(); BitmapManager.instance().cancelThreadDecoding(mDecodingThreads); } @Override protected void onDestroy() { super.onDestroy(); if (mBitmap != null) { mBitmap.recycle(); } } Runnable mRunFaceDetection = new Runnable() { @SuppressWarnings("hiding") float mScale = 1F; Matrix mImageMatrix; FaceDetector.Face[] mFaces = new FaceDetector.Face[3]; int mNumFaces; // For each face, we create a HightlightView for it. private void handleFace(FaceDetector.Face f) { PointF midPoint = new PointF(); int r = ((int) (f.eyesDistance() * mScale)) * 2; f.getMidPoint(midPoint); midPoint.x *= mScale; midPoint.y *= mScale; int midX = (int) midPoint.x; int midY = (int) midPoint.y; HighlightView hv = new HighlightView(mImageView); int width = mBitmap.getWidth(); int height = mBitmap.getHeight(); Rect imageRect = new Rect(0, 0, width, height); RectF faceRect = new RectF(midX, midY, midX, midY); faceRect.inset(-r, -r); if (faceRect.left < 0) { faceRect.inset(-faceRect.left, -faceRect.left); } if (faceRect.top < 0) { faceRect.inset(-faceRect.top, -faceRect.top); } if (faceRect.right > imageRect.right) { faceRect.inset(faceRect.right - imageRect.right, faceRect.right - imageRect.right); } if (faceRect.bottom > imageRect.bottom) { faceRect.inset(faceRect.bottom - imageRect.bottom, faceRect.bottom - imageRect.bottom); } hv.setup(mImageMatrix, imageRect, faceRect, mCircleCrop, mAspectX != 0 && mAspectY != 0); mImageView.add(hv); } // Create a default HightlightView if we found no face in the picture. private void makeDefault() { HighlightView hv = new HighlightView(mImageView); int width = mBitmap.getWidth(); int height = mBitmap.getHeight(); Rect imageRect = new Rect(0, 0, width, height); // make the default size about 4/5 of the width or height int cropWidth = Math.min(width, height) * 4 / 5; int cropHeight = cropWidth; if (mAspectX != 0 && mAspectY != 0) { if (mAspectX > mAspectY) { cropHeight = cropWidth * mAspectY / mAspectX; } else { cropWidth = cropHeight * mAspectX / mAspectY; } } int x = (width - cropWidth) / 2; int y = (height - cropHeight) / 2; RectF cropRect = new RectF(x, y, x + cropWidth, y + cropHeight); hv.setup(mImageMatrix, imageRect, cropRect, mCircleCrop, mAspectX != 0 && mAspectY != 0); mImageView.mHighlightViews.clear(); // Thong added for rotate mImageView.add(hv); } // Scale the image down for faster face detection. private Bitmap prepareBitmap() { if (mBitmap == null) { return null; } // 256 pixels wide is enough. if (mBitmap.getWidth() > 256) { mScale = 256.0F / mBitmap.getWidth(); } Matrix matrix = new Matrix(); matrix.setScale(mScale, mScale); return Bitmap.createBitmap(mBitmap, 0, 0, mBitmap.getWidth(), mBitmap.getHeight(), matrix, true); } public void run() { mImageMatrix = mImageView.getImageMatrix(); Bitmap faceBitmap = prepareBitmap(); mScale = 1.0F / mScale; if (faceBitmap != null && mDoFaceDetection) { FaceDetector detector = new FaceDetector(faceBitmap.getWidth(), faceBitmap.getHeight(), mFaces.length); mNumFaces = detector.findFaces(faceBitmap, mFaces); } if (faceBitmap != null && faceBitmap != mBitmap) { faceBitmap.recycle(); } mHandler.post(new Runnable() { public void run() { mWaitingToPick = mNumFaces > 1; if (mNumFaces > 0) { for (int i = 0; i < mNumFaces; i++) { handleFace(mFaces[i]); } } else { makeDefault(); } mImageView.invalidate(); if (mImageView.mHighlightViews.size() == 1) { mCrop = mImageView.mHighlightViews.get(0); mCrop.setFocus(true); } if (mNumFaces > 1) { Toast.makeText(CropImage.this, "Multi face crop help", Toast.LENGTH_SHORT).show(); } } }); } }; public static final int NO_STORAGE_ERROR = -1; public static final int CANNOT_STAT_ERROR = -2; public static void showStorageToast(Activity activity) { showStorageToast(activity, calculatePicturesRemaining(activity)); } public static void showStorageToast(Activity activity, int remaining) { String noStorageText = null; if (remaining == NO_STORAGE_ERROR) { String state = Environment.getExternalStorageState(); if (state.equals(Environment.MEDIA_CHECKING)) { noStorageText = activity.getString(R.string.preparing_card); } else { noStorageText = activity.getString(R.string.no_storage_card); } } else if (remaining < 1) { noStorageText = activity.getString(R.string.not_enough_space); } if (noStorageText != null) { Toast.makeText(activity, noStorageText, 5000).show(); } } public static int calculatePicturesRemaining(Activity activity) { try { /*if (!ImageManager.hasStorage()) { return NO_STORAGE_ERROR; } else {*/ String storageDirectory = ""; String state = Environment.getExternalStorageState(); if (Environment.MEDIA_MOUNTED.equals(state)) { storageDirectory = Environment.getExternalStorageDirectory().toString(); } else { storageDirectory = activity.getFilesDir().toString(); } StatFs stat = new StatFs(storageDirectory); float remaining = ((float) stat.getAvailableBlocks() * (float) stat.getBlockSize()) / 400000F; return (int) remaining; //} } catch (Exception ex) { // if we can't stat the filesystem then we don't know how many // pictures are remaining. it might be zero but just leave it // blank since we really don't know. return CANNOT_STAT_ERROR; } } }
尝试在调用recycle()方法之前添加它，以确保位图尚未被回收：
if (mBitmap != null && !mBitmap.isRecycled()) { mBitmap.recycle(); mBitmap = null; }
对于那些到目前为止还没有find解决scheme的人。 我有同样的问题。 我试图在onPause中像这样回收一个位图：
Drawable drawable = mImageView.getDrawable(); if (drawable instanceof BitmapDrawable) { BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable; Bitmap bitmap = bitmapDrawable.getBitmap(); bitmap.recycle(); } if (preView != null && !preView.isRecycled()) { preView.recycle(); preView = null; }
返回后，我得到了exception：“canvas：试图使用一个回收的位图”
对我的解决scheme：我不得不添加以下内容
mImageView.setImageBitmap(null);
在我的情况下，错误是由于我改变布局的一个元素的可见性（反之亦然）的可见性。 因此，imageview和位图创build的空间发生了变化，所以回收使应用程序崩溃。 避免这一点，你的问题将得到解决。
Android不允许我们重复使用已回收的Bitmap只需注释bitmap.recycle()即可解决此错误。 欲了解更多详情请点击这里
在我的情况下，我已经膨胀了包含imageview与src图像的布局，我面临着同样的错误。 这种情况下，问题可以通过编程添加源图像解决，如：
((ImageView)view.findViewById(R.id.imageview)).setImageBitmap(BitmapFactory.decodeResource(getContext().getResources(), R.drawable.testimage));
只要从代码中删除bitmap.recycle()来解决它。
