来自官方网站:http://developer.android.com/training/displaying-bitmaps/load-bitmap.html

ImageView image = (ImageView) findViewById(R.id.imagePreview);           
try {
    image.setImageBitmap(decodeSampledBitmap(picFilename));
} catch (Exception e) {
    e.printStackTrace();
}

方法如下:

    private int calculateInSampleSize(
            BitmapFactory.Options options, int reqWidth, int reqHeight) {
        // Raw height and width of image
        final int height = options.outHeight;
        final int width = options.outWidth;
        int inSampleSize = 1;

        if (height > reqHeight || width > reqWidth) {

            final int halfHeight = height / 2;
            final int halfWidth = width / 2;

            // Calculate the largest inSampleSize value that is a power of 2 and keeps both
            // height and width larger than the requested height and width.
            while ((halfHeight / inSampleSize) > reqHeight
                    && (halfWidth / inSampleSize) > reqWidth) {
                inSampleSize *= 2;
            }
        }

        return inSampleSize;
    }

    private Bitmap decodeSampledBitmap(String pathName,
            int reqWidth, int reqHeight) {

        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(pathName, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        return BitmapFactory.decodeFile(pathName, options);
    }

//I added this to have a good approximation of the screen size: 
    private Bitmap decodeSampledBitmap(String pathName) {
        Display display = getWindowManager().getDefaultDisplay();
        Point size = new Point();
        display.getSize(size);
        int width = size.x;
        int height = size.y;
        return decodeSampledBitmap(pathName, width, height);
    }   

你可以使用:

ImageView imgView = new ImageView(this);
InputStream is = getClass().getResourceAsStream("/drawable/" + fileName);
imgView.setImageDrawable(Drawable.createFromStream(is, ""));

大多数答案都是有效的，但没有人提到高分辨率的图像会降低应用程序的速度，在我的情况下，我使用了imagesrecyclerview，它在30张图像中占用了0.9 GB的设备内存。

我/编舞:跳过73帧!应用程序可能也在这样做 它的主线有很多工作要做。

解决方法很简单，你可以像这样降低质量:降低位图的分辨率

但我用简单的方式，Glide处理剩下的工作

fanContext?.let {
            Glide.with(it)
                .load(Uri.fromFile(File(item.filePath)))
                .into(viewHolder.imagePreview)
        }

       public static Bitmap decodeFile(String path) {
    Bitmap b = null;
    File f = new File(path);
    // Decode image size
    BitmapFactory.Options o = new BitmapFactory.Options();
    o.inJustDecodeBounds = true;

    FileInputStream fis = null;
    try {
        fis = new FileInputStream(f);
        BitmapFactory.decodeStream(fis, null, o);
        fis.close();

        int IMAGE_MAX_SIZE = 1024; // maximum dimension limit
        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)));
        }

        // Decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;

        fis = new FileInputStream(f);
        b = BitmapFactory.decodeStream(fis, null, o2);
        fis.close();

    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    return b;
}

public static Bitmap showBitmapFromFile(String file_path)
{
    try {
        File imgFile = new  File(file_path);
        if(imgFile.exists()){

            Bitmap pic_Bitmap = decodeFile(file_path);
            return pic_Bitmap;

        }
    } catch (Exception e) {
        MyLog.e("Exception showBitmapFromFile");
        return null;
    }
    return null;
}   

如果你在列表视图中使用图像加载，那么使用Aquery概念。

https://github.com/AshishPsaini/AqueryExample

     AQuery  aq= new AQuery((Activity) activity, convertView);
            //load image from file, down sample to target width of 250 pixels .gi 
    File file=new File("//pic/path/here/aaaa.jpg");
    if(aq!=null)
    aq.id(holder.pic_imageview).image(file, 250);

onLoadImage满载

private void onLoadImage(final String imagePath) {
    ImageSize targetSize = new ImageSize(imageView.getWidth(), imageView.getHeight()); // result Bitmap will be fit to this size

    //ImageLoader imageLoader = ImageLoader.getInstance(); // Get singleto
    com.nostra13.universalimageloader.core.ImageLoader imageLoader = com.nostra13.universalimageloader.core.ImageLoader.getInstance();
    imageLoader.init(ImageLoaderConfiguration.createDefault(getContext()));

    imageLoader.loadImage(imagePath, targetSize, new SimpleImageLoadingListener() {
        @Override
        public void onLoadingStarted(final String imageUri, View view) {
            super.onLoadingStarted(imageUri, view);

            progress2.setVisibility(View.VISIBLE);

            new Handler().post(new Runnable() {
                public void run() {
                    progress2.setColorSchemeResources(android.R.color.holo_green_light, android.R.color.holo_orange_light, android.R.color.holo_red_light);

                    // Picasso.with(getContext()).load(imagePath).into(imageView);
                    // Picasso.with(getContext()).load(imagePath) .memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE).into(imageView);

                    Glide.with(getContext())
                            .load(imagePath)
                            .asBitmap()
                            .into(imageView);
                }
          });
        }

        @Override
        public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
            if (view == null) {
                progress2.setVisibility(View.INVISIBLE);
            }
            // else { 
              Log.e("onLoadImage", "onLoadingComplete");
            //   progress2.setVisibility(View.INVISIBLE);
            // }
            // setLoagingCompileImage();
        }

        @Override
        public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
            super.onLoadingFailed(imageUri, view, failReason);
            if (view == null) {
                progress2.setVisibility(View.INVISIBLE);
            }
            Log.e("onLoadingFailed", imageUri);
            Log.e("onLoadingFailed", failReason.toString());
        }

        @Override
        public void onLoadingCancelled(String imageUri, View view) {
            super.onLoadingCancelled(imageUri, view);
            if (view == null) {
                progress2.setVisibility(View.INVISIBLE);
            }
            Log.e("onLoadImage", "onLoadingCancelled");
        }
    });
}

来自官方网站:http://developer.android.com/training/displaying-bitmaps/load-bitmap.html

ImageView image = (ImageView) findViewById(R.id.imagePreview);           
try {
    image.setImageBitmap(decodeSampledBitmap(picFilename));
} catch (Exception e) {
    e.printStackTrace();
}

方法如下:

    private int calculateInSampleSize(
            BitmapFactory.Options options, int reqWidth, int reqHeight) {
        // Raw height and width of image
        final int height = options.outHeight;
        final int width = options.outWidth;
        int inSampleSize = 1;

        if (height > reqHeight || width > reqWidth) {

            final int halfHeight = height / 2;
            final int halfWidth = width / 2;

            // Calculate the largest inSampleSize value that is a power of 2 and keeps both
            // height and width larger than the requested height and width.
            while ((halfHeight / inSampleSize) > reqHeight
                    && (halfWidth / inSampleSize) > reqWidth) {
                inSampleSize *= 2;
            }
        }

        return inSampleSize;
    }

    private Bitmap decodeSampledBitmap(String pathName,
            int reqWidth, int reqHeight) {

        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(pathName, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        return BitmapFactory.decodeFile(pathName, options);
    }

//I added this to have a good approximation of the screen size: 
    private Bitmap decodeSampledBitmap(String pathName) {
        Display display = getWindowManager().getDefaultDisplay();
        Point size = new Point();
        display.getSize(size);
        int width = size.x;
        int height = size.y;
        return decodeSampledBitmap(pathName, width, height);
    }